Epoxyworks 23 Is Also Available As A

® EPOXYWORKS ®

Number 23 n Spring 2006 BUILDING, RESTORATION & REPAIR with EPOXY

Onne van der Wal In this issue EPOXYWORKS®

1 Scheherazade update Editors Kay Harley, Jennifer Jones A late look at the Hodgdon-built, Bruce King-de- Designer Michael Barker signed, 154' ketch. Subscriptions Kristen Lore 2 The limitations of statues What to do when your shepherd gets cold feet and Contributors W. D. Bertelsen, Tim Botimer, Jason Havel, falls apart under a little stress. Brian Knight, Bruce Niederer, Tom Pawlak, Patrick Ropp, 4 Fabricating an air scoop J. R. Watson and Jeff Wright Using the “lost foam” method to build a custom air Epoxyworks is published twice a year by Gougeon Brothers, scoop for a race car. Inc.,BayCity,MIUSA. 6 Building a masthead fitting Product number 000-605 Building a custom sailboat part with a molded cavity also using the “lost foam” method. ©2006 by Gougeon Brothers, Inc. Reproduction in any form, in whole or in part, is expressly forbidden without the 8 If you can’t take the heat... written consent of the publisher. An explanation of the effects of high temperatures on cured epoxy and what HDUL really means. Epoxyworks, Gougeon Brothers, WEST SYSTEM,105, 205, 206, 207, 209, 403, 404, 405, 406, 407, 410, Episize, Scarffer, and 10 Rebuilding an International 110 Microlight as used throughout this publication are trade- Tim Botimer wins a national championship after re- marks of Gougeon Brothers, Inc. building a 110 that sailed in the 1941 Nationals. Subscriptions, US and Canada Epoxyworks subscriptions 12 Readers’ projects are FREE to US and Canadian addresses only. Subscriptions Epoxyworks readers using WEST SYSTEM® epoxy in expire automatically after 6 issues (three years). If your sub- some very skilled and innovative ways. scription expires with this issue, “LAST ISSUE”appears next to 14 Comparing cost and weight of flat panels your name on the mailing label on the back cover. To start or A detailed comparison of flat panels built with lami- renew a subscription or subscribe for a friend, complete and nated and composite materials. return the tear out mailer or call 989-684-7286. You may also subscribe via E-mail to [email protected] (be sure 16 Practical uses for razor blades to include your mailing address) or by filling out the sub- Here are a few of the many uses single-edged razor scription form at epoxyworks.com or westsystem.com. Our blades have in a shop where epoxy is used. mailing list is strictly confidential. 17 Building a Guillemot kayak Subscriptions, foreign addresses For addresses in Mexico Jason Havel puts his own touches on a stripper-built and Central and South America, there is a $6.00 (US) post- kayak and does it with the heat turned up. agefeefora6issuesubscription.Subscribebycalling 18 Giving Bounty Hunter a new skin 989-684-7286 or faxing 989-684-0687. Please include along with your complete mailing address, your credit card num- How Captain Glenn James sheathed the hull of his 65' ber, expiration date and signature—Visa, MasterCard and charter fishing boat and improved her performance. Discover only. 20 Building a planter box In Europe, Africa and points east, contact Wessex Resins, An elegant solution to the problem of building a 44-1-794-521-111. In Australia, New Zealand, and the far “cheap” planter box. east, contact ATL Composites, 61-755-377-636. See page 25 22 Improved mold strongbacks for additional contact information. How we built stiff supports for molds that required Contribute to Epoxyworks If you have completed an in- very tight tolerances and spanned up to 70'. teresting project, or developed a useful technique or a practical or unusual use for epoxy, tell us and your fellow 23 Staudacher strongbacks epoxy users about it. Send a photograph or two, or email A variation of the plywood strongback designed for digital photos (about 300 dpi). Include a note describing building airplane wings. the project and how to contact you. 25 Information/contact Mailing address Epoxyworks Did we mention that the 5th Edition of The Gougeon PO Box 908 Brothers on Boat Construction is finally available? Bay City, MI 48707-0908 26 Big bicuspid E-mail [email protected] A Quebec sign maker thinks big. Epoxyworks online epoxyworks.com

EPOXYWORKS Cover story

Onne van der Wal Billy Black Scheherazade update

While Epoxyworks was out of circulation, we missed reporting on an important epoxy event, the launching of the 155' ketch, Scheherazade, at Hodgdon Yachts in East Boothbay, Maine. We are a little late in the reporting, but cannot let the event pass without acknowledging this beautiful union of wood/epoxy technology, elegant design, and supe- rior craftsmanship. You may recall from Epoxyworks 17and19thatScheherazade was to be one of the largest cold molded wood/epoxy vessels ever built in the United States. Her 3½" thick hull is made of inner and outer layers of 7 8" Douglas fir planking running fore and aft and separated by four di- 7 agonal layers of 16" western red cedar bonded with WEST SYSTEM® epoxy. Douglas fir replaces the cedar in highly loaded sections of the hull. All fasteners used to install deck hardware (including the massive winches) are glued in place with epoxy thickened with high-density Onne van der Wal fillers. Interior cabinetry is black walnut and fiddleback sycamore. Interior details include hundreds of shells, starfish, and other marine life that were hand-carved from single blocks of wood. With a staff of up to one-hundred people working on Scheherazade at one point during the build, the project took approximately four years to complete. She was launched on September 27, 2003. Visit hodgdonyachts.com for a look at past projects and progress on Billy Black the Ted Fontaine-designed 98' ketch currently under construction. n Scheherazade Designer...... BruceKing Interiordesigner...... AndrewWench LOA...... 154'-7" Beam...... 28'-6" Draft...... 13'-0" Mainmastheight...... 174' above the deck Mizzenheight...... 110' above the deck Sailarea...... 9,940sqft Hullthickness...... 3½" Barehullweight...... 110,000 lb Dana Jinkins Billy Black Ballastkeelweight...... 150,000 lb

Number 23, Spring 2006 1 the Statue of Liberty. The goal is nothing less than perpetuity. But of course, outdoor sculp- Thelimitations ture needs to be done right or it won’t last. Making statues, i.e., permanent structures that look like people, is particularly difficult. One recent December, I received a call from a fellow member of St. Luke’s United Methodist Church in Essexville, Michigan. St. Luke’s was ofstatues attempting to deploy an outdoor nativity scene composed of a number of life-like, molded-fiberglass figurines. The problem was that the shepherd figure was damaged and could not take his watch. By W.D. Bertelsen The figurines were high-quality pieces with in- tricate detailing, made by a local Christmas or- Creating lasting outdoor art has challenged nament firm. However, while they had been humans since the dawn of time. One has only manufactured to very high artistic standards, to think of the pyramids (still there), the figurines were structurally unsound for Stonehenge (mostly there), the Colossus of outdoor use. The manufacturer provided no Rhodes (long gone), or the Easter Island means for anchoring them down. In previous monoliths (surviving, but then two heads are years, volunteers had simply attached each to better than one). In more recent times, there’s a plywood slab with big toggle bolts through a Mt. Rushmore, Stone Mountain Georgia, and thin bottom panel. They then spiked the slab corners into the ground. In due time, a typical Michigan winter froze Shep to the earth as if cast in concrete. A hasty post-season shove, intended to release him, instead fractured the tenuous joint between the sides of the pedestal and the bottom panel en- gaged by the toggle bolts. Shep had broken off all the way around the edges of his pedestal (Photos 1 & 2). It was not a premeditated crime. The charges were “baseless.” I got the call because it was known at St. Luke’s that I work for an epoxy company. (Few are aware that my specialty is testing composite materials to destruction. I am much more experienced at breaking structures, to measure their strength, than at repairing them.) However, I knew our knowledgeable 1 GBI technical staff might be able to devise a repair strategy that I could handle.

1 & 2— Shep after being knocked off his base. 3—The gluing area of the pedestal was prepared for bonding by thoroughly abrading the surface with a wire wheel tool on a cordless drill.

2 EPOXYWORKS 4—A bead of thickened epoxy in the outline of the pedestal was applied to the new base. 5—After the pedestal was lowered onto the bead of epoxy, a large fillet was created around the exterior of the joint

4 5

It was clear that the base/pedestal joint needed to be redone with WEST SYSTEM® epoxy. The old polyester-encrusted base was discarded andreplacedwithasandwichcompositepanel left over from past GBI test programs. I found an undamaged two-foot-square panel with a foam core and thick fiberglass face sheets. In order to effect a rugged, epoxy bond to the sandwich panel, it was imperative to take full advantage of the generous surface area af- forded by the pedestal sides. GBI’s Tom Pawlak emphasized the need for good, pre-bond surface preparation. He produced a wire wheel tool with which to scuff the perimeter to create fresh bonding surface (Photo 3). Thus began a series of lunch-hour work ses- sions. I kept at it until I got below the paint 6 and into the glass fibers. I cleared enough width to accommodate a generous fillet of mulate in the field, I drilled a ¼" hole in the filled epoxy. The plan was to go with WEST 1 middle of the base. I also drilled an 8" hole 6 —Shep (far right) was SYSTEM 105/206 containing enough 407 under each of Shep’s elbows to allow air pres- back on duty with Low-Density Filler to create a mayonnaise sure to release during bonding. These holes twelve days to spare. consistency, ideal for filleting. would also allow equalization whether Shep Before mixing the epoxy, I placed Shep on his was on winter display or in summer new base with the textured side up and traced stand-down in a hot storage shed. around the sides of the pedestal with a perma- To complete the surface preparation for bond- nent marker. Removing Shep, I had a guide ing, I used the wire wheel to abrade the tex- line that would permit me to trowel on filled tured glass surface of the new base on either epoxy with enough precision so that the glue side of the pedestal outline. We applied epoxy could grip the inside of the pedestal as well as to the base and to both the inside and outside the outside. The inside blind fillet would effec- of Shep’s pedestal rim (Photo 4). With the new tively double the joint strength. base face up on the workbench, we lowered While I was tracing the perimeter, Tom had a Shep into position and crafted the exterior fil- quietly brilliant suggestion: install a series of let (Photo 5). stainless deck screws just inside the perimeter The finishing touch was to coat the foam line to be engulfed by the epoxy, further en- edges of the new base with neat WEST W. D. Bertelsen is the hancing the grip. It was done in minutes. SYSTEM105/206. After an overnight cure, Chief Testing Engineer It was my idea to through-bolt the sandwich Shep was ready to return to the St. Luke’s. at Gougeon Brothers. faces in several areas to discourage the start of Thanks to WEST SYSTEM epoxy, the complete This the first recorded a peel that might separate the upper joint face display was back on line, with still twelve days incidence of Bill not de- from the foam core. For drainage of internal to go before Christmas Eve (Photo 6). n stroying an object after moisture and condensation that might accu- gluing it together.

Number 23, Spring 2006 3 The “lost foam” method of composite fabrication

“Lost foam”composite fabrication uses Styrofoam™ as a male mold, over which composite materials are applied. The Styrofoam isthendissolvedoutofthecuredpartwithacetoneor lacquer thinner, leavingahollowedoutshell. (Other typesoffoammaynot dissolve, so use styrenated foam exclusively for this process.) It is used to produce custom (one-off) parts with a molded interior cavity. Since the moldisdestroyedafter the partisbuilt, thisversion of the lostfoammethodisnotaproduction process. With this method, any shape that can be carved or molded out of Styrofoam can be turned into a fiberglass/epoxy composite. For example, this method can be used to fabricate air scoops and intake plenums for combustion engines, masthead fittings, and various types of nozzles or plumbing applications. Brian Knight and J.R. Watson recently built small composite parts that required a specific hollow space. Both used the lost foam method to build the parts. These articles demonstrate two different approaches to a problem and how the method can be modified to suit individual needs. Fabricating an air scoop

1 By Brian L. Knight I used lost foam construction to fabricate a fi- damaged (a very likely scenario), the repair berglass air scoop for my son’s Formula Conti- will be simpler. To fabricate the scoop, I made nental C race car. Our project started because a Styrofoam male mold, surrounded the mold a modification to the shape of the race car with fiberglass, and then dissolved the Styro- body necessitated the construction of a new foam to leave a hollow part. I used Styrofoam air scoop. The air scoop is bolted to the car to build the male mold for several reasons. It body so if either the air scoop or the body is is readily available at most lumberyards, it is easy to shape with files and sandpaper, and it is easy to dissolve with lacquer thinner. Carve/shape a Styrofoam blank The blank was built up of several layers of foamandthencarvedtoshape.Tobuildthe blank, I used WEST SYSTEM® epoxy because it does not chemically attack the foam. How- ever, the hard glue lines at each layer of foam can cause difficulties when shaping the part. 1—Viewed from behind, Styrofoam has a density of about 2 pounds per the finished Styrofoam cubic foot—very low. Unless the density of the mold carved to fit in glue line approximates the foam, the shaping place on the body where 1 it will be installed. process will remove foam much more quickly than the glue lines. This leaves unacceptable ridges at each joint in the foam. So to make shaping easier, I used epoxy thickened with 410 Microlight™ to glue the layers of Styro- foam together. Microlight has a very low density and does not make hard glue lines that 2—The air scoop mold viewed from the front. other fillers might. The mold is in the pro- I used Surform™ tools, coarse files, and sand- cess of being covered paper to shape the mold. I made no attempt to with clear packaging get a good surface finish on the mold—I just tape to prevent epoxy concerned myself with the overall fairness. from bonding and to provide a smooth Since fiberglass will not conform to sharp cor- interior surface in the 2 ners, I used fillets of 410 Microlight on all in- finished part. side corners.

4 EPOXYWORKS I used clear packaging tape as a mold release the air scoop. This made a perfect fit between The term lost foam is also (Photos 1 and 2). One thing to pay attention the two parts. Then I removed the tape from used in metal casting. to—epoxy does not adhere to the shiny side of the body. Similar to the lost wax method, the foam or wax the tape, but it will lock itself into wrinkles Because this part was built on a male mold, it is an exact pattern of the and gaps in the tape. So, do a neat job of ap- required considerable fairing. I used epoxy finished part within a plying the tape to avoid difficulty removing thickened with 410 Microlight to make an sand or plaster mold, the tape from the cured part. easily sanded fairing compound. This was ap- which is displaced by mol- plied with a plastic spreader and allowed to Apply the fabric ten metal. I applied a couple of layers of wet-out fiber- cure. Lots of hand and block sanding later, the glass cloth to the bottom of the foam and part was almost ready for paint (Photos 5 and In lost foam composite wrapped it up the sides a few inches. Then I 6). To seal the sanded 410, I applied one last fabrication, the foam is a allowedthistocure. seal coat of neat epoxy. core or male mold over which the finished part is The next step involved sanding the cured edge built. of the fiberglass where the first application ended. There were lots of sharp “hairs” stick- ing up as well as several wrinkles in the glass. I carefully sanded this area smooth, taking care not to gouge into the Styrofoam immediately adjacent to the cured glass. Then I applied several layers of fiberglass to the remainder of the part. These overlapped the previously applied cloth (Photos 3 and 4). When all the epoxy had cured, I sanded enough so that I could handle the part safely 3—The fiberglass has cured over the Styro- without getting cut on sharp edges and then 3 foam mold before it is cut a hole through the bottom fiberglass skin. trimmed and sanded. This hole was sized to allow the carburetor and air cleaner to fit inside the air scoop. The hole also provided access to the inside of the scoop to make the job of removing the foam easier. Dissolve the foam and clean up the inside Lacquer thinner will effectively dissolve Styro- foam. Poured slowly over the foam, the lacquer thinner reduces the foam to a viscous blue liquid. When the lacquer thinner evapo- rates from the liquid, it leaves a small, hard plastic residue. For the air scoop, I used about 4—The cured part and a cup of lacquer thinner. mold from below before After dissolving the foam, reach in and remove 4 the foam was dissolved the epoxy “ribs” that are left. The ribs are the with lacquer thinner. epoxy layers (which are not attacked by the solvent) used to laminate the layers of foam. They need to be removed by hand. The tape will generally remain with the part and will peel off after the foam is destroyed. This will also allow the removal of the fillets that are left after the foam is dissolved. 5—The cleaned up part Finish the scoop after cleaning out the I wanted the air cleaner to fit precisely to the interior and fairing the exterior with epoxy/410 top of the car body. To accomplish this, I ap- Microlight Filler. plied clear packaging tape to the body, applied a layer of 410 Microlight to the tape, and 410 fairing compound was also used to make a placed the air scoop in the putty. The 410 did 5 body-conforming base not stick to the tape; it stuck to the bottom of for the air scoop.

Number 23, Spring 2006 5 After a final wet sanding of the seal coat, I sprayed several heavy applications of lacquer primer on the part. This was wet sanded and two coats of Omni™ automotive paint were applied. One more wet sanding followed by a coat of Omni Clear finished the job (Photos 6 and 7). n

6—The finished air scoop viewed from the front. The lost foam method of composite fabrication was ideally suited for the scoop’s aerodynamic shape.

7—Viewed from the top, the finished air scoop with two coats of white automotive paint and 6 7 one clear coat.

Building2 a masthead fitting By J.R.Watson

Here’s another use of the lost foam method to (Photo 2). Then I rounded over and smoothed produce a custom part with a molded interior the corners with sandpaper (Photo 3).I cavity. In this case, the part was a mast head bonded the sculpted foam blank to a tempo- fitting to hold an internal sheave and provide rary base to facilitate handling and applied a route for the halyard to pass. This method paste wax to the mold to fill the porosity of The masthead fitting had can be adapted to a variety of other applica- the foam. This was done to produce a several design require- tions, as demonstrated in the previous article. smoother surface and promote release of lami- ments: Making the foam mold nate later on. • It must fit within an ex- The first step was to make a full-size drawing Applying the fabric isting spar size and 1 of the fitting to use as a reference for manu- Next, I applied a 8"thicklayerofWEST shape. facturing (Photo 1). Using the drawing, I fash- SYSTEM® 105/205 epoxy (thickened to a • It must have sufficient ioned Styrofoam to represent the fitting’s grease-like consistency with 406 Colloidal Sil- wall thickness to bear internal void. I bonded pieces of foam to- ica and 423 Graphite Power) over the entire expected forces. gether to produce a billet of sufficient size, us- part. ing the bond lines for a centerline to aid in I wet out strips of woven graphite fiber rein- • It must house the measurements. (By using more layers of foam, sheave and provide ade- forcement and pressed them into the thick- you could use the additional glue lines each ened mixture until I achieved an estimated quate room to internally side of the centerline to produce contour lines route the halyard. thickness of ¼". (Any more than this could for additional shaping guides.) have resulted in excessive exothermic temper- • It must offer an attach- From the drawing, I made templates of the atures.) While the laminate was still wet, I ment point for the top- two side views. I taped them to the foam billet covered it with plastic (a freezer bag) and ping lift. so I could rough-out the mold on a band saw wrapped it with self amalgamated tape. This

6 EPOXYWORKS consolidated the laminate, extruding excess resin out the bottom. Reducing resin content to around 45% resin/55% fiber improves mechanical properties. Then I allowed it to cure. I removed the cured part from the temporary base and dug out the foam with a carving chisel, hand-held rotary tool (Dremel™), file, and knife. As I approached the wax-covered exterior surface of the mold (now the interior surface of the masthead fitting), the foam fell 1—Make a full-size off, revealing and replicating the sculpted sur- drawing of the part to face. make templates and use 1 as a reference for manu- Then, I applied additional layers of fabric. I facturing. first applied another thickened epoxy/406/423 layer, which helped span minute surface irreg- ularities. I used braided reinforcing material for these layers, taking care to overlap and align successive layers. Tape was produced by cutting braided sleeve material. With braid, fiber orientation can be adjusted simply by com- pressing or tensioning the material. I used templates made from the drawing to aid in es- tablishing the finished shape/size. Round templates produced from paper towel core made 2—Make templates of for accurate sizing of round sections. After the two side views and achieving the shape I wanted, I allowed the fi- tape them to the foam billet. Use a band saw to nal layers of fabric to cure. 2 cut out the rough shape I located the sheave axle hole by measuring off of the mold. the drawing with calipers. I first drilled under- size to check for accuracy with the real part and then drilled to axle size. You can make the 3—Then round over and topping lift of various materials; in this in- smooth the corners with stance, I stitched nylon line together and sandpaper. wrapped it with thread for flexibility and light 4—The nearly finished weight. I bonded the fiber part of the line to fitting with a duplicate the crown of the fitting and covered it with of the foam mold. After fairing compound and a layer of braided tape the inside was cleaned (Photo 4). out, additional fabric was applied to achieve A tip for mounting the fitting to the mast the final exterior shape. To prevent obstructing the passage with adhe- The outside was faired and shaped before the sive when the fitting is installed into the top of 3 topping lift and sheave the mast, I inserted a common balloon cov- were installed. ered with a thin layer of Vaseline™ down into the cavity. I inflated it after the fitting was inserted into the masthead, thereby pressing any Sheave axle invading excess adhesive against the spar and Shaped out of the way of the halyard. The balloon foam core Shaped fairing also exerted sufficient force to prevent any compound minute movement from the fitting’s intended location until cure-up was achieved. The Vase- linemadeiteasytoremovethedeflatedbal- loon after everything had cured. Final blending and touch-up was done after Topping lift cure-up, and a cover of carbon fiber braided Sheave sock was applied as further reinforcement. Af- Interior cavity Braided carbon fiber ter a final coating and sanding, the fitting was 4 matches foam core reinforcing primed and painted. n

Number 23, Spring 2006 7 If you can’t take the heat … Understanding the effects of high temperatures on cured epoxy

By Bruce Niederer

Among both professionals and amateurs in the The most commonly used and misunderstood world of composites, there are certain endur- term is heat deflection under load (HDUL), of- ing misconceptions and rumors regarding the ten shortened to simply the heat deflection effects of elevated temperature on an epoxy temperature (HDT). This shortened name bond. Armed with just enough misinformation helps to breed some of the confusion. HDUL to be dangerous, folks will make important is a standard test (ASTM D-648) used indus- decisions that can lead to costly or time-con- try-wide to characterize the thermal behavior suming mistakes that might have been avoided of a resin system. The test determines the tem- if they had an adequate understanding of the perature at which a bar or coupon of cured 1 principles that encompass epoxy structures epoxy (without reinforcing fibers) 8"thick× and temperature. By defining some commonly ½" wide × 5" long and under a point load of 7 used terms and briefly discussing issues sur- 264 psi will deflect 0.1" (~ 64"). The test sam- rounding application, we hope to dispel some ple is loaded in the test apparatus and simply of these misconceptions. supported at both ends, on edge, and the load is applied in the center—a typical three-point 1—The test apparatus bend test (Photos 1 & 2). Then the sample is holds five of the test loweredintoanoilbaththatheatsslowlyup samples shown below in from room temperature and stops when the a bath of heated oil while a three-point load sample deflects the 0.1" (Photo 3). is applied to the sample. The misconceptions are that above this temperature the epoxy no longer has any structural integrity, adhesive strength, and/or that it 2—This shows how the even begins to return to a liquid state! None load is applied to the of these correctly characterizes what is hap- coupon of epoxy. The pening. With an understanding of how HDUL coupon is still solid, but is measured, it should seem obvious that the has bent, illustrating the epoxy becomes more flexible as the tempera- concerns regarding 1 creep. ture rises above room temperature (typically 72°F), but the epoxy is still quite strong. Al- though it is true that there are epoxy systems on the market formulated to have an HDUL lower than room temperature, these epoxies are for specific, non-structural applications. Here’s an example which demonstrates that epoxy retains its structural integrity and adhesive strength after exposure to high temperatures. We have glued two blocks of mahogany together with WEST SYSTEM® epoxy, allowed it to cure for one week at room temperature, and then exposed the whole assembly to 200°F for 3 hours before forcing a chisel into the glue line to fail the joint. When the joint was examined closely, we found that the primary failure was in the wood and not the epoxy. Experience has also shown that while 2 heat tends to soften epoxy while it remains warm, if WEST SYSTEM epoxy is not exposed

8 EPOXYWORKS 3—A gauge ods serves to define a point at which A close look at a WEST SYSTEM Te c h - measures the cured epoxy, which is an infusible nical Data Sheet shows that we report deflection of solid, becomes a rubbery solid. A the “onset of Tg” measured from the the epoxy sample as the tem- good way to visualize this is to think firstheatcycle,aswellasthe“ulti- perature of the of a rubber garden hose left out in the mate Tg”, which is from the second oil bath winter versus the same hose in the heat cycle. We believe onset of Tg is increases. summer. In the winter it’s hard and the most useful value to report be- stiff, in the summer it’s soft and flexi- cause it’s not practical for anyone to ble—but either way, it’s still a garden post cure their project to 392°F and, 3 hose. in fact, epoxy can be damaged by ex- We believe the temperature that a posure to this high a temperature. manufacturer reports in the product Now this may be hard to accept, (es- to damaging heat (exceeding 230°F literature for glass transition should pecially during this political season for extended periods), it will return to be within a few degrees of the HDUL where honesty is valued at such a pre- full strength when cooled to room temperature for the design and engi- mium), but some manufacturers re- temperature. neering reasons outlined above. How- port the ultimate value and don’t What this test does not reveal is the ever, often times the Tg is bother to tell their customers! I know, behavior of a loaded or pre-stressed significantly higher. The reason for I know, it’s shocking—but business bond line. Joints of this nature are the discrepancy lies in how the test is can be brutal. Regardless, the practi- subject to static or constant loads, of- performed and subsequently re- cal implications from the Tg informa- tenreferredtoascreep loads.When ported. We measure Tg by DSC, tion are the same as discussed for the epoxy is used for building projects, which conforms to ASTM standard HDUL. this aspect of the design and engineer- D-3418, and choose to report the on- To summarize, keep in mind the ing must be considered.1 The antici- set of the transition. This results in a meaning of the terms and test meth- pated load and working temperature value close to the HDUL. It is also le- ods discussed in this article. HDUL of the joint may indicate that addi- gitimate to report the midpoint or means heat deflection under load and tional techniques be applied to insure endpoint—as long as you disclose it’s of key importance to remember the long-term viability of the joint. how Tg was determined. this element of the test when some- Such techniques can include using Here’s how it works. A small sample one refers to it as heat deflection tem- mechanical fasteners, increasing the of cured epoxy is placed in a small perature and wants to argue that the surface area of the bond, increasing aluminum crucible about ¼" in diam- epoxy will fail at this temperature. A the thickness of a composite laminate, eter and placed in the DSC machine 264 psi load is quite a significant or incorporating more thin lamina- next to an identical, but empty, cruci- load. So if a joint or bond line is not tions in a curved wood laminate so ble. This is the ‘differential’ aspect of loaded to a similar level, or is in fact each lamination has less stored en- the test. The test chamber is a small not loaded at all, the likelihood is that ergy. All of these reduce the effect of oven that can measure and record the neither the epoxy nor the joint will creep loading in a joint or lamination. differences in heat output and/or up- fail. Similarly, the glass transition tem- A more ambiguous term that is often take between the two crucibles. The perature, or Tg, if reported honestly, misunderstood by the end user is the oven then runs through a heating cy- defines the point where the epoxy be- glass transition temperature (Tg). This cle from 30°C (86°F) to 200°C gins a transformation to a rubbery term is also reported differently by (392°F) at 10°C/min and the minute solid. Most importantly, neither term various resin manufacturers, which differences in the heat output/input defines a temperature above which adds to the confusion. The glass tran- are recorded by the machine’s sen- epoxy cannot be used. Still, if your sition temperature can be measured sors. After this heating is finished, the joint will live in a working environ- by various methods, such as a Differ- oven cools and the heating cycle is re- ment at or near the HDUL or Tg tem- ential Scanning Calorimeter (DSC), peated; however, for this run, the ep- perature, then you should consider Dynamic Mechanical Analysis oxy sample has been effectively post the nature of the joint within the (DMA), a torsion pendulum, the di- cured by the initial heat cycle. As a re- structure to decide if epoxy alone is electric constant, volumetric methods, sult, the glass transition temperature sufficient or if other techniques are and even “bouncy balls”. Since the will nearly always be significantly called for. If you have questions, our value of Tg depends on the strain rate higher. In fact, ASTM D-3418 can be technical staff is available Monday and the heating/cooling rate, there interpreted to require the measure- throughFriday8:00a.m.to5:00 cannot be a single, exact value for Tg. ment of Tg from this second heat cy- p.m. EST by calling 866-937-8797 n Resin manufacturers use different cle to “erase thermal history.” From a toll free. methods and different reporting crite- formulator’s point of view, this data is 1 See “Designing for Rigidity and Strength ria for Tg, which leads to inconsisten- useful; from a builder’s point of view, under Static Load”in Modern Plastics Ency- cies when comparing data from it is not practical. clopedia 1986-87, p. 403 for a detailed dis- multiple sources. Each of these meth- cussion.

Number 23, Spring 2006 9 Rebuilding an International 110

By Tim Botimer

I first got into International 110 sailing 15 I replaced one of the oak keel frames and re- years ago and soon bought an old fixer-upper paired the others. I found that the ends were boat. After sailing it for a couple of years in a rotted where the screws that hold the chine on decrepit state, I made the decision to fix it to the frames went in. I scarfed a new end right. I had worked with WEST SYSTEM® onto one frame, and I used a Dutchmen scarf products before, and I was pretty familiar with to repair some rot on another. The frames the product line. I had done significant repairs were just like new. on a 1965 plywood Thunderbird and a 1950s After replacing all of the bottom frames to vintage Flying Dutchman, which incidentally give the boat the proper shape (Photo 2),I was one of the original test boats when Jan added stringers fore and aft to give more and Meade Gougeon first came out with the structural stability between the frames (Photo product. I had never tackled anything on the 3) and to prevent the bottom from sagging be- scale of the 110 project, and at the time it was tween the frames, especially where the boat the only boat I had. sits on the trailer. The frames and stringers The International 110 was designed by C. were coated with clear epoxy and then sanded 1—My International 110 Raymond Hunt, and many are home built. to allow for a mechanical bond. I used stain- (Number 300)with the Mine was Number 300, the first one produced less screws to hold things in place until the ep- glass and paint by Jesek Brothers boatbuilders of Holland, oxy hit its initial cure, and then I removed all 3 removed. Michigan. The boat is constructed of 8" of the screws. Douglas fir marine plywood over Douglas fir I planked the bottom first and then repeated frames. The four keel frames are white oak. It the process on the sides. Using marine grade sailed in the very first 110 Nationals in 1941. 3 8" Douglas fir plywood, I used a special tool The boat was showing its age, so the first tocuta7to1scarftojointheplywoodand thingIdidwasstripofftheheavyfiberglass make a continuous 24' piece. The plans call cloth on the hull to see what I really had for a butt joint; however, with the bottom ply (Photo 1). I knew I would be putting a new scarfed, the boat drains better. I used WEST bottom on at the very least, and I wanted to SYSTEM 105 Resin with 206 Slow Hardener. I know what I was getting into from the start. wet out the joint with straight resin/hardener, With the glass and paint (at least 10 coats, all andthenImixedupabatchwith403 of different colors) removed, I found that the Microfibers for gap filling. I clamped the ply- sides and the bottom were both dry-rotted wood together, and the resulting joint hardly along the seams. The bottom frames were still shows and is stronger than the original wood. in pretty good shape except that they were the Putting the bottom and sides on was a wrong shape. The first eight feet of the bot- three-person job. I had two people mixing tom was too flat and then there was a two resin/hardener and adding 406 Colloidal Silica inch hump where the keel frames were. and 403 Microfibers. They would mix up

After replacing all of the bottom frames(2) to give the boat the proper shape, I added stringers fore and aft (3) to give more structural stability between the frames.

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10 EPOXYWORKS 4 5 about a 5-pump batch from the mini pumps mixed with 422 Barrier Coat Additive (Photo 4—We scraped the excess epoxy off all of the and then add the fillers. The mix was then 6). This stuff worked great because it made surfaces on the inside loaded into the handy reusable caulk gun sanding and seeing imperfections easier. It also where it had squeezed tubes and applied to the frames and stringers. made the surface much more impervious to out and formed fillets Once the whole thing was glued and screwed, water. The exterior is finished with Interlux™, with the excess epoxy. all three of us climbed in and scraped the ex- Interthane Plus™ two-part polyester paint, ap- 5—I used epoxy/410 cess epoxy off all of the surfaces where it had plied with a roller and tipped out with a good Microlight™ to fair the squeezed out. Using the stir sticks, we formed brush. hull and extensively fair fillets with the excess epoxy (Photo 4).This International™ 110 Number 300 had a new the keel to the correct was quick and easy, and it made a much stron- lease on life (Photo 7). This rebuild was done shape. ger joint. in 1994, and I haven’t had to do any major To fair the hull, I used 410 Microlight™ and touch ups to the boat. In 2003, after winning epoxy, thickened to a thick peanut butter con- the National championships, I gave her a new sistency. I also used this mixture extensively to coat of paint. I have since done several other reshape the keel to the correct shape. Once 110 rebuilds and have learned a few tricks and the shape was achieved, I coated everything tips to make the job easier. Planning sure beats with several coats of the epoxy/barrier coat. sanding is probably the biggest lesson learned. I now use okume mahogany plywood instead 6—The exterior got seven coats of epoxy The keel is cast iron and very prone to rust of the Douglas fir. It is much more weeping through. I wire wheeled the keel mixed with 422 Barrier dimensionally stable. I also call the WEST Coat Additive. clean of rust and then wire brushed epoxy bar- SYSTEM Technical Services when I have a ques- rier coat onto the keel. I rolled the glue on tion instead of trying to figure it out on my 7—In 2003, after win- and then wire brushed it into the pores of the ning the National cham- own. The folks at WEST SYSTEM are very pionships, I gave her a cast. The next four coats were just rolled on knowledgeable and always willing to help. n one after another as soon as they were hard new coat of paint. enough to take another coat (Photo 5). WEST SYSTEM epoxy worked equally well for finishing off the exterior of the hull. The interior got three coats of clear epoxy and then varnish. The exterior got seven coats of epoxy

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Number 23, Spring 2006 11 This is a TALBOT LAGO T120 Baby Sport built in 1936 at Suresnes near Paris. In 1990, Claude Schmit,t a retired yacht bro- ker from Cannes, France, found the remains of the car under the leaves in a forest and spent 4,500 hours over eight years to rebuild it. Very few parts were sal- vageable. The body had to be completely rebuilt. A frame of laminated ash replaced the original solid ash frame. Schmitt says, “This is a wooden car, maybe one of very few. The most important feature is that, after 22,000 miles and four years of rather heavy use for such an old car, sometimes Paul Butler offers plans for this 3' wide and just under 12' long duck boat. It can be built rallying in very rough old roads, the entire completely open or decked over with coamings for weather protection. It can be rowed, body looks really great, as new. Absolutely sculled, poled, paddled, or powered with a small electric motor. The boat weighs in at 50 lb not one defect can be detected. Thanks to and will hold 2 adults and gear in an open configuration and can be car-topped. This ply- the famous WEST SYSTEM. Grateful apprecia- wood stitch and glue project is easy to build and could make a good wood/epoxy starter tion for all the people involved in this tech- project. Paul Butler, Box 1917, Port Angeles, WA 98362. Email: [email protected]. nology. I greatly enjoyed the work and I fully enjoy the use of it.”

Readers’ projects

Don Meyers of Cheboygan, Michi- gan, built this stripper bassinet for his first granddaughter. He used white cedar and WEST SYSTEM 105/207.

J. M. Hyslop of Hopkins, Michigan built this 24' Karl Stanbaugh- designed sailboat. The Emily P is built of Douglas fir, marine fir ply and WEST SYSTEM epoxy and draws less than 2' of water with the board up.

Cub Scout Pack #4120 from Sister Bay, Wisconsin, recently completed this 16' cedar strip canoe. Over 150 volunteer hours were logged by scouts, scout leaders, parents, and community volunteers. The canoe was donated to the scout’s charter organization, the Sister Bay Lion’s Club, in April, 2005. The project was overseen by craftsmen Bruce Yohe and Brian Buchholz.

12 EPOXYWORKS It took Ed VanKirk, of Constantine, Michigan, 3 years and 10 gallons of WEST SYSTEM epoxy to build this triple cock- pit, 19' barrel-back runabout. The boat, launched in April 2005, was designed by Ken Hankinson. It is powered by a 5.7 liter Volvo Penta conversion (Chevy 350), which turns out approximately 280 horsepower.

Ray Lynch built this site trailer to be used on major renovation projects. Lynch first considered a standing seam roof, but chose the fiberglass/epoxy roof for its strength, weather resistance, lower cost, and lower wind resistance. He planned on adding a plywood/glass/epoxy hold- ing tank for the sink and shower and a custom sink. Lynch lives in Odessa, Delaware.

These cedar-strip kayaks are based on “ancient skin boats of Cape Dorset, Baffin Island.” They were built by Phil Pike of Greensboro Bend, Vermont, using WEST SYSTEM 105/207 and 4 oz fiberglass cloth. Each boat took about 220 hours to complete, even though the boat on the right was assembled without using staples.

J. R. Beall built this clock to see if it was possible to run a clock with bow power. The bow clock is made of a variety of veneers bonded with WEST SYSTEM epoxy and a small vacuum press. This plywood is great because the parts made from it are absolutely stable and allow for very fine tooth profile. The bows are laminated of ash, cherry and ebony. The escape- ment is called a Grasshopper and is ideal for wooden works because it is free from friction and will not wear the surfaces. The running time of the clock is extended through the use of cords to provide what amounts to a block and tackle arrangement to multiply the movement of the bows. The cord is wound on a spiral grooved windlass called a fusee, which compen- sates for varying tension. Beall says he has used WEST SYSTEM epoxy for years, starting with a constant camber boat. He has started a forum for wood works clock builders, (www.bealltool.com/clockforum) which is open to all. Beall bides his time in Newark, Ohio.

Number 23, Spring 2006 13 or Howtochoosethebestmaterials when building with flat panels

By Jeff Wright

Many WEST SYSTEM® customers appreciate ricated panels. Baltek Corporation, ATL Com- the benefits of cored composite construction. posites, and others offer fiberglass balsa-cored They understand that it creates a part that is and fiberglass foam-cored panels that are lightweight, strong, and stiff. We often receive available in various thicknesses with polyester calls from these customers inquiring about us- or epoxy laminated skins. They can be ma- ing a composite panel when building or re- chined with normal woodworking tools. pairing something that would normally be These panels may cost more than laminating made of plywood. Such projects may include a your own, but labor will be reduced. new center console for a fishing boat or the Composite panels should have the edges replacement of flying bridge side shields. De- treated in a manner similar to plywood. The termining the best material requires consider- foam or balsa core should be sealed to prevent ation of many aspects of the project, but often moisture from entering. Low-density cores of- comes down to cost versus weight. ten require thickened epoxy to be applied to Panel types the exposed edges to protect them from dam- Plywood Panel construction requires that the age and to provide a good surface for the final panels be cut to fit and then sealed along all finish. the end grain with epoxy. The panels need to Cost be fastened in place with screws, wire ties, or Before taking on any project, it is always a good weight of flat panels Comparing cost and nails. The panels are then bonded together by idea to budget for the materials. Generally applying a fillet of thickened epoxy in the speaking, a composite panel will cost more than joint and possibly applying fiberglass tape. We compared the cost plywood. You will need to purchase the core Composite Panel and weight of four panel construction requires the material, reinforcing fiber (usually fiberglass), types: panels to be cut and assembled the same way and epoxy. Some core materials, such as balsa, but with the additional steps of laminating the will absorb more resin than many of the foams, • EpoxycoatedXL panel. The lamination process requires a which will also affect the cost of the composite. Plywood Boat Panel molding surface to be prepared with a mold A simple plywood panel only requires the • EpoxycoatedOkoume release and the materials need to be cut to the wood and enough epoxy for three coats of Marine Plywood required shape. The materials are wet out, moisture protection. If you use higher quality possibly vacuum-bagged, and then allowed to marine plywood and protect the plywood with • Epoxy/fiberglass/balsa cure. After the panel is cured, it is removed fiberglass cloth, the cost difference is reduced. cored composite from the mold and sanded to remove any Laminating fiberglass will require more epoxy sharp edges. Any mold release is removed than simply coating the wood. • Epoxy/fiberglass/core with the appropriate solvent, and the panel is cell foam composite Weight sanded to ensure good paint adhesion. Finally the needed shape is cut from composite panel, Weight reduction is the most common motiva- just as it would be from the plywood panel. tor for replacing plywood with a composite panel. The weight advantage of a cored panel A variation of composite construction, often re- over plywood increases as the panel gets ferred to as a “one-off construction,” is to build thicker because the lightweight core material the part using rigid sheets of foam or balsa core increases while the same amount of fiberglass material, and then laminate reinforcing fabric and resin are maintained. When the thickness to the shaped core. After the laminate has of plywood is doubled, the weight is doubled. cured, the part will likely need to be faired, be- However, if a ½" thick balsa core with 10 oz fore it is sealed with epoxy and painted. The fiberglass on each side is increased to 1" thick advantage is that one-off construction elimi- balsa, the weight only increases 60%. On pan- 3 nates the need for a molding surface. els less than 8", a composite panel may not You can reduce the labor and time involved in have a significant weight difference over ply- using composite panels by purchasing prefab- wood.

14 EPOXYWORKS Epoxy Coated Epoxy Coated SAN Closed Cell Figure 1—Cost Material Cost Cost Balsa Composite Cost Cost Plywood Boat Panel Okoume Plywood Foam Composite comparison of 3 XL Plywood Okoume Marine 8"x2'x4'panels Panel / Core $12 $21 Contourable Balsa $27 Core Cell Foam $38 Boat Panel Plywood Fiberglass* 2x745 (12 oz) Glass $30 2x745 (12 oz) Glass $30 Epoxy* 105 / 206 $9 105 / 206 $9 105 / 206 $11 105 / 205 $10 Total Cost $21 $30 $68 $78

Epoxy Coated Epoxy Coated SAN Closed Cell Figure 2—Cost Material Cost Cost Balsa Composite Cost Cost Plywood Boat Panel Okoume Plywood Foam Composite comparison of XL Plywood Okoume Marine ¾" x 2' x 4' panels Panel / Core $18 $36 Contourable Balsa $42 Core Cell Foam $54 Boat Panel Plywood Fiberglass* 2x745 (12 oz) Glass $30 2x745 (12 oz) Glass $30 *prices based on propor- tion of 745-10 size of Glass Epoxy* 105 / 206 $9 105 / 206 $9 105 / 206 $11 105 / 205 $10 Fabric and B Group of ep- Total cost $27 $45 $83 $94 oxyusedtobuilda2'x4' panel.

A cored composite panel can often perform as Thetypeofcorematerialandthefabricused well as plywood, even though it is significantly for the skins will also affect the overall stiff- lighter. When the face of a panel is loaded ness. Using carbon fiber instead of fiberglass with perpendicular force, the outermost sur- will increase stiffness when the core thickness face of the panel experiences the greatest load. cannot be increased. Different core materials This principle is why a lightweight core with also affect the stiffness. The density of a core thin fiberglass faces can carry significantly material often indicates its stiffness. Foam more load than the core material alone. The cores with very low density are not as stiff as combination of thin skins and lightweight core foam that is higher in density. The densities of can result in a panel as stiff and strong as foam can range from 2.5 lb/ft3 to over 30 plywood but with a lower weight. lb/ft3, giving a wide range of properties. The Stiffness high-density foams may make for a stiff panel, but the weight advantage over plywood is lost. Increasing the thickness of a panel will increase the stiffness exponentially. You can see Remember that there is a difference between this with a yardstick. In the flat direction, it is stiffness and strength. Stiffness is often used as very easy to flex; on edge, it is nearly impossi- the primary measurement when composites ble to bend by hand. Using a core material to are designed for boats. When a panel is stiff increase the thickness will increase the stiffness enough for an application, in many cases it is very effectively. strong enough and will have a long fatigue

Epoxy Coated Epoxy Coated SAN Closed Cell Figure 3—Weight Material Wt. Wt. Balsa Composite Wt. Wt. Boat Panel Plywood Okoume Plywood Foam Composite comparison of 3 XL Plywood Boat Okoume Marine 8"x2'x4'panels Panel / Core 8.5 lb 7.5 lb Contourable Balsa 2.4 lb Core Cell Foam 1.25 lb Panel Plywood Fiberglass 2x745 (12 oz) Glass 1.3 lb 2x745 (12 oz) Glass 1.3 lb Epoxy 105/206 1.0 lb 105/206 1.0 lb 105/206 2 lb 105/206 1.3 lb Total Weight 9.5lb 8.5lb 5.7lb 3.85lb

Epoxy Coated Epoxy Coated SAN Closed Cell Figure 4—Weight Material Wt. Wt. Balsa Composite Wt. Wt. Boat Panel Plywood Okoume Plywood Foam Composite comparison of ¾" x 2' x 4' panels XL Plywood Boat Okoume Marine Panel / Core 16 lb 15 lb Contourable Balsa 4.75 lb Core Cell Foam 2.5 lb Panel Plywood Fiberglass 2x745 (12 oz) Glass 1.3 lb 2x745 (12 oz) Glass 1.3 lb Epoxy 105/206 1.0 lb 105/206 1.0 lb 105/206 2 lb 105/206 1.3 lb Total Weight 17 lb 16 lb 8.05 lb 5.1 lb

Number 23, Spring 2006 15 life. Swim platforms, decks, and hardtops are Earlier we looked at how to calculate the situations where a stiff panel is needed to re- weight of the new panel and compare it to sist flexing and eliminate the perception of be- plywood. This may only be part of the overall ing soft or spongy. In these cases, the panel is weight of the entire structure. For example, if probably so stiff that the strength is higher the component being built is a seat, then you than needed to avoid a failure. need to consider the hardware, seat cushion, When composites are used for critical or and insulation on the back to determine the highly loaded areas, such as bulkheads, string- percent weight reduction for the entire assem- ers, and hull bottoms, strength needs to be bly. A 40% weight reduction in the panel may considered. Calculating the needed strength only be a 20% weight reduction of the entire requires a good understanding of the loads ap- assembly. Also be sure to consider any addi- plied and the mechanics of cored construction. tional hardware backers that you may need Before using a composite panel, step back and since many light cores will not hold screws as analyze the situation. Then determine how the well as plywood. panel is loaded and what the consequences are Plywood that is completely sealed in epoxy Plywood that is com- of a failure. In many instances, the project is will last for many years and offers good bal- pletely sealed in epoxy straightforward, but if there are any concerns, ance between weight and strength. However, will last for many years contact an engineer or designer. if weight reduction is a priority, cored com- and offers good balance The Details posite panels may be the ideal material. Be between weight and sure to closely examine the time and money strength. Since weight reduction is the most common required and how much weight will be re- reason for using a cored composite panel, it moved. With careful planning, you can use However, if weight reduc- deserves a little more attention. Spending this method of construction successfully to tion is a priority, cored some time to calculate the weight savings will help lighten the boat. n composite panels may be help you determine if the results will be worth the ideal material. the time and money.

Practical uses for razor blades By Tom Pawlak The trick is to dull the razor blade slightly with 600-grit sandpaper. Round the corners at each end of the blade at the Necessityis themotherofinvention,andrazorblades areoften same time. Then, try the blade on an inconspicuous spot to called into service for a variety of tasks around the shop other be sure it does not scratch the surface. than shaving. Here are a few. Theedgeofthebladeactsasaverythinwedge.Itworksbest Mini-spreader if you start at the end of the drip that is thinnest. If you can Razor blades can be used in a pinch to apply caulks and get a peel started, you can usually get the drip off without thickened epoxies with great precision. They do a great damaging the gelcoat, Formica™, or well-dried painted sur- job filling isolated pinholes and scratches, especially face. The razor blade will remove all but the most stubbornly when the blade is laid at a low angle (nearly flat) when adhered drips of hardened epoxy or dried paint. spreading the putty. When we were production building the Gougeon 32 sail- Mini-scraper boats, we found dulled razor blades remarkable for remov- Sharp razor blades can be used as cabinet scrapers. Use with ing drips of cured epoxy from gelcoated surfaces. Even thebladeonedgeat90°orsotothesurface.Scrapeoffsmall cured epoxy smudges often came off. Without this tool, we imperfections like drips and dirt specks in cured/dried coat- were forced to sand off the hardened drips and buff back the ings before buffing or final sanding. shine, which was time-consuming work. Dull razor blades also make useful tools A dulled razor blade also works great for removing old bath- tub caulk on fiberglass tub and shower surrounds without Everyone knows how handy sharp razor blades are for remov- damaging the gelcoated surfaces. Be sure to try the dulled ing dried paint from windows. But single-edge razor blades blade on an inconspicuous spot to verify that is isn’t scratch- can be modified for removing cured epoxy and dried paint ing the surface. If the blade gets a little rough on the edge, drips on surfaces that are less scratch resistant, like gelcoat, run it over the 600-grit paper and smooth it out again. n Formica™, and other plastic laminates.

16 EPOXYWORKS Building a Guillemot kayak

By Jason Havel

I am a Captain in the Air Force and was stationed in Wichita, Kansas, in October2002 when I purchased Nick Shade’s book, How To Build A Strip Kayak.Afterthefirst chapter, I was sold. I ordered the full-size plans for the Guillemot. While on vacation in Texas, I spent about $300 on the western red cedar, purpleheart, and yellow heart, then discovered I was to deploy to Saudi Arabia. In the evenings prior to the deployment, I machined the cedar into ¼" strips and put the bead and cove on them using a router table. It was during the process of setting up my table saw that I realized how clear D-grade pine can be. I accidentally bought a few long boards of it to build an extra long, table saw fence for ripping the cedar. I was amazed how little grain was visible. That’s where the idea of the lighter colored deck came from. 1 I got 6 or 8 strips on the mold before I left for my deployment. While I was gone, the confrontation with 1—The stripping of the Iraq began. What was supposed to be 3 months turned hull with western red ce- into 5 months. The air-war ended and I came home and dar is completed. was informed I would be moving from Wichita, Kansas, to Altus AFB, Oklahoma. I knew it was only 300 miles, but I wasn’t about to bring a couple hundred strips of cedar and an unfinished boat along for the trip. I spent every spare moment finishing the boat. I finished strip- 2—The inside of the hull ping in June, laid the fiberglass in July, and moved in is glassed with 6 oz fi- August. berglass cloth. Havel used 105/207 to wet out I used 6 oz cloth with 105 Resin/207 Hardener and was 2 the cloth in tempera- very impressed. Since July in Kansas is typically over tures over 100°F. 100°F, I was a little hesitant pouring epoxy. When I did all the epoxy work, it was 108° to 112°F. I could thoroughly mix the epoxy, lay it down, brush or squeegee it out, and make it look perfect. Ten minutes later, it started to harden. There were no issues with sheeting or running. In fact, I never saw any anime blush and had zero bubbles. Believe me, I looked for anime blush since every piece of literature mentions it. After an hour or two, I brushed on the next coat to fill the weave and add a nice smooth surface for the varnish. Since the epoxy wasn’t fully cured, I got an excellent chemical bond. I can’t say enough about how great the 207 Hardener worked at over 100°F. I coated everything with epoxy, 3 including the deck fittings, before I fastened them to the deck. I sanded the hull with 150-grit sandpaper on a 3 & 4—Purpleheart pro- random orbital sander and finished it off with five coats vides a nice contrast for of Z-Spar™ Captains Varnish. Z-Spar also works great the outline of the deck at 100+ degrees. design and deck hard- I’d do it again in an instant but next time it will be a ca- ware. noe since my family will soon be a total of four plus our Everything is coated with 105/207 and fin- dog. Even though the kids will be small, it’s tough to ished with 5 coats of stuff them and my wife in a single place kayak and ex- 4 Z-Spar Captains Varnish. pect to get anywhere. n

Number 23, Spring 2006 17 vessels, regardless of construction, to Bounty Hunter pull a sampling of planking fasteners Giving at regular intervals during credit dry dock or when other indications provided the necessity to do so. An inves- anewskin tigation found that degraded fasteners on the El Toro II caused a few planks By Patrick Ropp to come loose and fail when she en- countered heavy seas. Examination of ive years ago, Captain Glenn Any wooden boat repair has to be other planks after the vessel was re- James decided it was time to looked at holistically and take into ac- covered showed that while many of make improvements to his Coast count the owner’s requirements and F the fasteners looked good on the sur- Guard-inspected charter fishing boat the vessel’s construction, condition, face, half of them throughout the ves- operating out of Edgewater and Solo- and service. (See the WEST SYSTEM selwerewastedwithinthe mon’s Island on the Chesapeake Bay. 002-970 Wooden Boat Restoration & plank-to-frame joints to the point of Bounty Hunter is a 65' cedar-strip Repair Manual for a fuller discussion providing no structural integrity. planked hull, a one-off Davis™ hull of this and of techniques described in built in 1967 at Harkers Island, this article.) In this case, Coast Guard Captain James wanted to explore ave- North Carolina. The planks are fas- inspection requirements also had to nues to minimize or eliminate the re- tened to frames on 16" centers with be taken into consideration. Captain quired pulling of fasteners, which in some instances could cause more The 65' strip-planked damage than good, on Bounty Bounty Hunter after Hunter. Unlike El Toro II, Bounty sheathing with Hunter was originally glued and fiberglass and WEST nailed together in a monocoque, ce- SYSTEM epoxy. After 5 dar-strip construction, so the skin acts years, she still looks as good as she did as one complete shell. Vessels con- then. In addition, her structed like this are ideal candidates new skin quickly paid for sheathing with fiberglass and ep- for itself though oxy because they require considerably increased less preparation. Once a vessel is performance. sheathed, she will be considered a “composite” hull, one made of different materials, and consequently be subject to less stringent and invasive inspection standards than a traditional wooden vessel. CaptainJameswasrequiredtoseek monel fasteners. The cedar strips are James and his son, Glenn, Jr., decided Coast Guard permission prior to narrow, less than 2" wide, and are to restore Bounty Hunter by sheath- modifying the vessel. Here is the pro- edge nailed with monel nails and edge ing the hull with epoxy and fiberglass. cess that WEST SYSTEM recom- glued. They not only added many more mended. The Coast Guard approved An experienced and successful night years to Bounty Hunter’s life, but the the plan and monitored each step charterer, Captain James knew his the dryer and lighter hull decreased carefully throughout the project. wooden vessel well but found the up- her draft by 6", increased her top Sheathing Bounty Hunter proved to keep and maintenance had increased speed from 15 knots to 22 knots, in- be an excellent decision, and the pro- overtheyears,takingmoretimeaway creased fuel efficiency, and gave a ject was completed without reserva- from fishing and family. He was ready smoother ride for paying passengers. tion by any of the parties. to minimize the maintenance and Coast Guard requirements Hull preparation hoped to increase performance at the After the traditional carvel-planked Preparation is a common thread in same time. Having used WEST wooden vessel, El Toro II,sankinthe any project. Sheathing a wooden hull SYSTEM® epoxy for other jobs, he Chesapeake Bay in 1993, taking the with fiberglass is no different. Sheath- turned to the technical staff at lives of one crew member and two ing is only recommended for vessels Gougeon Brothers for advice and as- passengers, the Coast Guard devel- that have planks that are edge glued sistance. While Gougeon Brothers oped new policy, the Navigation and together and are securely attached to does not typically visit vessels, J.R. Vessel Inspection Circular (NVIC) the frames.The following steps were Watson was attending a surveyor con- 7-95. This policy required owners of takentoensureBounty Hunter was ference in Annapolis and agreed to all Coast Guard-inspected wooden structurally sound prior to sheathing. look at Bounty Hunter.

18 EPOXYWORKS All paint and loose material were re- case, it was applied vertically. Edges After 5 years of service, the hull is moved from the exterior of hull. and seams were staggered at least 3" clean and shows no sign of degrada- The vessel was thoroughly inspected to gain full advantage of the fiber- tion. It has held up to the extreme en- for damaged or deteriorated hull glass’ strength. vironment charter vessels face and has planks, seams, and fasteners. Any de- Fiberglass application given Captain James a hull with mini- graded items were removed and re- mal maintenance. Awlgrip and other Applying the cloth was tiring and re- two-part polyurethane finishes, al- placed in kind. Wood replacement quired 3 “animals” with stamina and adhered to applicable Coast Guard though not inexpensive, are among strength. The two layers were com- the toughest on the market and have regulations and policies, such as pletely applied in just four days. Work NVIC 7-95. At least an 8:1 scarf is proven themselves in all types of ad- was done for about two hours on one verse conditions. normally recommended for scarfing layer and, once this was tacky, a sec- new planks into place, but longer ond layer was applied on the tacky Continued maintenance= scarfs are always a good option to first layer to promote a primary long-term satisfaction maximize the bonded surface area. chemical bond between the two lay- Continued maintenance ensures the Any deteriorated seams were cleaned ers. Once applied, the cloth was longevity of a wooden boat restora- and old material removed. Mixed ep- worked hard to remove any en- tion project. Deterioration in the final oxy, thickened with 403 Microfibers trapped air since air pockets in a lami- painting system needs to be addressed to a peanut butter consistency, was nate can reduce its strength as soon as practical to limit exposure forced into the seams to bond the dramatically. A resin-to-fiber ratio of to ultraviolet rays of the sun. Dings planks back together as needed. 50:50 by weight produces optimum and cracks to the hull also need to be Monel fasteners similar to the original physical properties for a hand-laid quickly addressed to maintain the oneswereusedtorefastenplanks. laminate. However, a higher percent- moisture barrier and protection that High spots on the hull were taken age of mixed resin is acceptable and the new sheathing provides to the down because the fairer the original not uncommon. A resin-starved lami- composite skin. nate can weaken the structure. hull is prior to sheathing, the easier Ventilation also cannot be overem- the final hull will be to fair later. The first layer was applied so that the phasized. Captain James evaluated the The moisture content of the vessel resin-rich chopped strand mat was ventilation in Bounty Hunter and de- was checked prior to sheathing to en- next to the prepped hull to improve termined that plenty of air was being sure that it was between 8%-12%. adhesion. Even though the Bounty changed throughout the vessel, in- Remember to use a moisture meter Hunter was painted white, the second cluding the bilges and other voids. recommended for the specific applica- layer was applied with the mat out- Keeping the boat’s interior as dry as tion (wood, fresh water service, salt side to help prevent print-through. possible is the best preventive mainte- water service, etc.); otherwise errone- A layer of epoxy/407 Low-Density nance for preserving the structure. ous readings may be obtained. fairing compound was applied to the Time is the test Sheathing material fiberglass surface and faired later. Up Bounty Hunter was sheathed 5 years to a ¼" of fairing compound was ap- WEST SYSTEM 105 Resin was used ago and still looks as good as she did with 206 Slow Hardener, combined plied to create fairness throughout the then. In addition, her performance at the proper mixing ratio, 5 parts length of the 65' vessel. The fairing characteristics increased, so the new 105 Resin to 1 part 206 Hardener by layer also helped to disguise skin paid for itself quickly. Because of weight or volume. To make volumet- print-through and minimize its ef- success of Bounty Hunter’s restora- ric measuring easier, a cylindrical fects. tion, Glenn James, Jr. has taken on mixing pot with straight, vertical sides Final fairing and finishing five similar projects since then. and a metering stick with pre-mea- Bounty Hunter was sanded to remove The successful sheathing of Bounty sured marks were used. Quality con- high areas and then faired. The fair- Hunter with fiberglass and WEST trol was in keeping with WEST ing compound consisted of WEST SYSTEM epoxy gave Captain James SYSTEM 000-742 Quality Assurance SYSTEM 407 Low-Density Filler and and the Coast Guard confidence to Considerations. Quality control the same 105/206 epoxy used in the turn a wooden boat into a lower dyes—yellow to the resin, blue to the laminate, mixed to peanut butter con- maintenance composite hull. Now, hardener—were added at the factory. sistency (approximately 12 oz of filler with less time spent to maintain When a consistent green color was to 1 qt of mixed epoxy). wooden boats, there’s more time to obtained, the two parts were properly enjoy the fishing. n mixed and ready to be applied. Once the hull was sanded fair, two coats of Awlgrip™ High Build Primer Patrick Ropp was a Gougeon Brothers The fiberglass cloth was two layers of were applied, followed by one coat of Technical Advisor until 2001 when he 7.5 oz biaxial (+/- 45°) cloth stitched regular primer. Bounty Hunter was returned to active duty as Lieutenant to .8 oz chopped strand mat. The ori- finished off with one coat of Awlgrip Commander in the Coast Guard. He is also entation of the fiberglass (vertical or paint. pursuing an engineering degree at horizontal) was insignificant; in this Michigan State University.

Number 23, Spring 2006 19 Building a Planter Box

By Brian L. Knight

My wife gave me the basic guidelines for a The bottom planter box she wanted me to build. First, On the sheet of ¾" treated plywood, I drew keep it cheap. Second, she wanted an “L” the “L” shape, using the dimensions specified shape. Third, she provided some rough di- by my wife. For the round corners, I used the mensions. The design was up to me. Logic cardboard shipping tube to lay out the curve. seems to abandon me when I design some- The edges of the plywood base have a 15° thing, and this project was no exception. A bevel to provide the flare for the sides. I cut all nice, straightforward box with square corners the straight line sections on my table saw and should have been the default. But after some sawed the round corners with a saber saw set doodling on paper, I decided to build a planter at a 15° angle. with flared sides and rounded corners. The sides First, the inexpensive part I ripped the ¼" lauan plywood into pieces I looked around my shop and found a scrap of about 15" wide (tall) to make the sides of the ¾" treated plywood left over from another planter. Because the sides are leaning out 15°, project. This made a good bottom for the the plywood sides are wider at the top and planter. I found enough ¼" lauan plywood to narrower at the bottom. I set the miter gauge make the sides, and I made the molds for the on my saw to 75° to cut the ends of the lauan curved corners from an empty cardboard ship- pieces. These pieces were glued to the 15° ping tube. As for the design, I decided on a 5 bevel previously cut on the bottom piece with flare of 15° for the sides and a radius of 2 8" a uniform gap left at the corners. The sides (the radius of the shipping tube) for the cor- were also filleted to the bottom to provide ad- ners. ditional surface area for the glue joint. The corners 1—The planter began as sheets of ¼" lauan ply- The gap at all the corners would be filled by wood temporarily con- laminated fiberglass; however, I needed a tem- nected by sections of porary mold to bridge the gap between the 5¼" diameter cardboard plywood sides and give the proper curved shipping tube at the cor- shape to the corners. I sawed sections of the ners. The shipping tube shipping tube long enough to be used as male held the plywood sides molds. I applied packaging tape to the card- in position while acting board for mold release, but cooking parch- as a mold for laying up permanent fiberglass ment paper or waxed paper would have corners. 1 worked just as well. I cut the bottom of the tubes to approximately 23°, so they rest on the bottom piece. Masking tape secured the sections of tubing at the top and one drywall 2—The ¼" gap at the edge of the plywood screw in the bottom (Photo 1). sides was filled with I applied a thick mixture of WEST SYSTEM® thickened epoxy. A layer epoxy/410 Microlight™ to the taped surface of glass tape was laid and applied 6" fiberglass tape to the wet mix- over the corner and ture. I smoothed the fiberglass with my hands smoothed into the thickened epoxy. The glass to distribute the epoxy/410 evenly below the was then wet out with cloth (Photo 2) andappliedneatepoxytofin- epoxy and the edges ish wetting the cloth. After allowing the were sanded smooth coated fiberglass to cure, I feathered the edges when cured. 2 of the tape and applied one layer of 6 oz cloth to the entire outside of the planter, followed

20 EPOXYWORKS 3—After the mold/tubes were removed, a layer of 6 oz cloth was applied to the exterior. Holes were drilled in the bottom for drainage. 4—Excess glass was trimmed flush with the edge of the plywood, and the interior was given a couple of coats of epoxy. 3 4 by several coats of neat epoxy to fill the weave 5—The top trim was of the cloth. This layer of cloth ties the entire made from redwood box together (Photo 3). When the epoxy with cedar corners. The cured, I faired the outside of the planter with square cedar corner lots of sanding. I drilled several ¾" drain holes blocks were fastened to in the bottom (Photo 3) and later glued on the end of the redwood strips with biscuits. The wood pads so the planter would have a little blocks were later air circulating under it (Photo 6). trimmed to shape and Finishing the edges of the entire trim assembly were At the top edge of the planter, I trimmed the eased with a round-over excess fiberglass and ground the corner pieces bit. even with the plywood edge (Photo 4).Topre- 5 vent moisture from attacking the plywood, I coated the inside surfaces with a couple of 6—Blocks were glued to coats of epoxy. the bottom for air circu- Next,Ifabricatedandinstalledthetoptrim lation and the sides that covered the raw edges of the plywood were glued to the trim. and fiberglass. It was made from redwood 7—When the planter with cedar corners for contrast (this was the was properly posi- one area where I departed from my wife’s tioned, the sides were attached to the trim original specification of “cheap”). To with short fillets. rough-out the trim ring, I cut square corner blocks and fastened them to the end of the 8—The finished planter. redwood strips with biscuits (Photo 5).The The trim was coated with 105/207 epoxy and square blocks made installing the biscuits 6 finished with spar var- much easier than trying to work with rounded nish. corners. The blocks were later rounded with a saber saw and the edges of the entire trim assembly were eased with a ¼" radius round-over bit. Epoxy fillets fastened this assembly to the planter sides (Photo 7). I coated the top of the planter with WEST SYSTEM 105/207 and then varnished with 3 coats of Captain’s™ 1015 Spar Varnish. The sides were painted with the house paint I use on the trim of my house (Photo 8). n

Short fillets

7 Trim 8

Number 23, Spring 2006 21 Improvedmoldstrongbacks

By Tom Pawlak.

Back in the 1980s, Gougeon Brothers was one skinny “I” beams. Initially, everything worked of the largest producers of wind turbine blades well. But as the seasons changed and the wood in the US. The blades were built of wood ve- picked up moisture, and the summer tempera- neer and epoxy, and varied in length from 10' tures in the shop went up, we were pushing to 70'. They were built in halves and vacuum the limits of the tolerances. The engineers fig- laminated in female molds built with WEST ured it was a combination of forces caused by SYSTEM® Brand Epoxy. Tolerances were tight, wood’s volumetric change, with changes in and every aspect of the tooling was critical, moisture content and difference in coefficient from molding to assembly. If something wasn’t of thermal expansion between the wood right when the two halves were glued to- strongback and epoxy/fiberglass molds. Our gether, there wasn’t much you could do to short-term fix was to cut the mold free from make it right later. the strongback and isolate it with plywood 3 The most difficult tolerances to maintain were supports ( 8" thick) that were installed perpen- span-wise straightness and twist. Early dicular to the length and located every 16" to strongbacks for molds and assembly jigs were 24" apart. They ranged from 4" tall at the root made of wood and were built like tall and end to 12" tall at the tip end of the mold. The differences in height were due to the fact that the molds were tapered to mimic the blade This box-beam half-geometry (thick at the root end and ta- strongback supports a pered to thin at the tip). The plywood sup- female mold for a 70' ports were attached to the top of the Westinghouse wind tur- strongback and to the backside of the mold bine blade. (The plug that was used to build with thickened epoxy fillets. Separating the the mold is in the mold.) mold from the strongback with the thin plywood supports meant slight changes in length The strongback is 5 between the two did not cause a problem. stiffened by 8" rebar glued into 1½"×1½" This is because the supports easily deflected to longitudinal stringers, allow relative movement but had almost no ef- one in each corner and fect on span-wise straightness. Luckily the one along the top and problem was caught early, but we decided we bottom surfaces. needed a better strongback design that would be more stable. The solution was to make a box beam out of ½" plywood sides, top and bottom plywood and epoxy. This in itself provided ¾" plywood bulkheads every 24" significant improvement, but the engineers went one step further. They incorporated steel rebar originally designed for reinforcing concrete into the four corners of the box beam. The rebar, welded to full lengths, was glued into 2"×2" wood stringers that ran full length along the four corners of the box beam. To make room for the rebar, a slot was cut into the wood stringers that was wide enough and deep enough to accept the steel. Epoxy thick- Casters are mounted ened slightly with 403 Microfibers was used to inside between fill the gaps in the groove surrounding the bulkheads to lower rebar after it was in position (Figure 1). mold's working height 3 On molds up to 20' in length, we used 8"di- 5 8" steel rebar bonded with epoxy/403 Microfibers ameter rebar. On larger molds, we used ½" or 5 8" diameter. The 70' long mold strongbacks 1½"×1½" wood stringers with a dado slightly larger than the rebar 5 Figure 1 were reinforced with 6 stringers made of 8"

22 EPOXYWORKS diameter rebar, one in each of the four corners and an extra one in the middle between the Female mold corners of the top and bottom. Whenthestrongbackswereusedforbladeas- sembly jigs or for saw jigs, they were anchored to the floor to keep things stable. If the ¾ "plywood strongbacks were used to support molds, bracing wheels were mounted inside the strongback (on the larger molds) to keep the center of gravity low and to keep the height of the mold 3 reasonable. On smaller molds where the width 8" plywood supports isolate the of the strongback was too narrow for a caster mold from the to pivot inside the bow beam, the wheels were strongback mounted on the outside of the structure. plywood bracing Mounting wheels under molds with heavy-duty aligns with bulkheads caster strongbacks can present some dilemmas. The wheels tend to get in the way of your feet. If 3 you mount wheels under the mold strongback, Wheel Assembly 8" plywood sides and top you need to shorten the height of the Exploded view ½" plywood bulkheads 3 strongback to make up for the wheel height. Figure 2 1½"×1½" wood stringers with 8" steel rebar Otherwise, the mold gets too high for people to work on. Unfortunately, shortening the height makes the strongback less stiff, which This allowed room for the wheels to pivot can be a problem. without getting in the way. Mounting the wheels inside the strongback After the blade halves cured, they were pulled works best as long as you allow room for from the molds, positioned in saw jigs, and wheels to swivel without interference. Another trimmed along the leading and trailing edges. option is triangular shaped strongbacks. We From there, the blade halves were moved to found this to be the best solution for 20' to 30' glue jigs where a shear web was installed on mold lengths. By positioning one of the three the inside of the high-pressure side. Eventu- sides horizontally, wheels could be mounted ally, the two halves were glued together with under the mold on angled brackets (Figure 2). thickened epoxy. n Staudacher strongbacks By Brian L. Knight

Jon Staudacher, of Staudacher Hydroplanes and Aircraft, has been using a long, very flat, work table/strongback that is mounted on casters. The table was originally 32' long, but because of space considerations, Jon has since shortened it to 20' (Photo 1). Four rubber casters support it, one at each corner (Photo 2). 1—This table is used to Jon uses this table as a surface to assemble air- assemble airplane plane wings, so it cannot have twist or sag. Be- wings. It must not twist cause of its stiffness, the table is not dependent or sag. The table was on having an extremely level floor. When the originally 32' long, but table is moved to a different location, it is easy has been shortened to to shim it level. It is stiff enough that it does 20'. Four rubber casters, not sag, and if there is a little twist, it is easily one at each corner, sup- shimmed out. Since the tabletop is the refer- port it. Built as a strongback, it spans 20' ence point for all objects being built, the table 1 (previously 32') without does not have to be perfectly level, but it must sagging.

Number 23, Spring 2006 23 2— Four rubber casters, one at each corner, are mounted to brackets at the ends of the table to give it portability.

3—Access holes to storage spaces are centered between the top and bottom rails, and have oval ends. 2 3 4—The 1×4s that sandwich the top and bottom of the front and back have no twists. If Jon expects to use weights holes are centered between the top and panel are scarfed to im- for clamp pressure, as he often does when bottom rails, and have oval ends. These are prove straightness. building the frames for wings, he temporarily important dimensions. If the access holes were shims the bottom rail of the table so it cannot sawn too close to the bottom or top surface, sag under the weight. The table doubles as a the table would lose its rigidity. Because square strongback with grid lines drawn on the top corners can cause stress concentrations, the for locating frames. holes have rounded ends (Photo 3). A table like this has to be built carefully, but Full or half sheets of plywood are used where the materials that go into the construction are ever possible. Construction starts by very light and readily available. The table is a sandwiching the top and bottom of the front long box beam made with plywood, and all and back panel between two 1×4s (Photo 4), pieces are glued together to make the table whichwerescarfedtogethertoimprove very rigid. There are plywood bulkheads every straightness. A ¼" plywood bottom panel was 4' to keep the front and back of the table from glued to the bottom rails. Then ¼" plywood buckling. In turn, the front and back of the ta- bulkheads and supports for the top were in- ble keep the top flat, without twist. The top is stalled. The top was glued to the top of the supported on 16" centers to prevent any side rails, bulkheads, and supports. Finally, drooping of the plywood top between bulk- brackets of scrap OSB were bolted to the ends 4 heads. In order not to waste space, storage is of the table to support casters (Photo 2). n built into the front of the table. The access

Brian Knight steps down Randy Zajac steps up Brian Knight, a WEST SYSTEM® Technical Advisor and contribut- Randy Zajac spent a few summers here as an intern while at- ing Epoxyworks editor since 1992, has retired. Despite the cur- tending Ferris State University. After graduating with a BS in mudgeon persona that no one bought for a minute, Brian’s Plastics Engineering, he is back as our newest WEST SYSTEM steadying influence and sage advice will be missed by cus- Technical Advisor. tomers and by those who worked with him. His technical He has lots of experience using epoxy for repairing composite knowledge reflects the depth of his experiences in research body panels on his own snowmobiles, trucks, and jet skis. and product development and as a highly-skilled builder. When he’s not repairing his toys, Randy enjoys finding ways to In previous lives, he was a teacher and a building contractor. make them go faster. He also races cross-country mountain He restored older houses, built new bikes in the Michigan Mountain Bike buildings, repaired wooden boats, Association Championship Point Se- built racing hydroplanes, and created ries expert class. He hopes to win a a 40' composite sculpture. race on a homemade advanced com- He has been building a stitch and glue posite frame someday. power boat for a number of years now. Randy is currently working in a group In his new life, we’re certain he will to build a 12' Shellback Dinghy and have more than enough time to finish will be working on a vacuum infused this project, entertain his grandkids, kayakandastripplankcanoeonhis and improve his golf game. n owninthenearfuture.n

24 EPOXYWORKS For information about WEST SYSTEM® products or Information/contact technical information for a building or repair project, West System, Inc. offers a range of detailed publications Contacts for WEST SYSTEM product that can help you get started. and technical information These publications are available at your local WEST NorthandSouthAmerica SYSTEM dealer or by contact- WEST SYSTEM INC. ing West System, Inc. P.O. Box 665 Bay City, MI 48707 The Gougeon Brothers on Boat Construction — 5th Edition available www.westsystem.com Our usual Epoxyworks schedule has been on hold for most of 2004 and 2005 Phone 866-937-8797 or 989-684-7286 while our editors and technical staff completed the 5th Edition of The Fax 989-684-1374 Gougeon Brothers On Boat Construction. Technical Services/Health & Safety This edition comprises a thorough review of best practices, 20% new and up- dated material, and a revised layout for easier navigation. Each chapter was Phone 866-937-8797 or 989-684-7286 reconsidered in terms of evolving technology, new techniques, and the suc- Fax 989-684-1287 cesses and failures of over thirty-five years of experience. We believe that the Order Department updates and improvements will enhance the value of this reference text for Phone 866-937-8797 or 989-684-7286 amateur and experienced professional alike. Fax 989-684-1374 You will find detailed discussions of a wide variety of wood/epoxy boat build- Europe,AfricaandtheMiddleEast ing techniques, along with focused discussions on interior construction, application of fabrics and fiber reinforcements, and much more. We spent WESSEX RESINS & ADHESIVES LTD considerable time and attention on updating the chapters on hardware and Cupernham House, Cupernham Lane fastener bonding, a hallmark of versatile, high-performance wood/epoxy con- Romsey, England SO51 7LF struction. The simple proven techniques outlined in the book provide build- www.wessex-resins.com ers with a durable high-performance technology suitable for marine and Phone 44-1-794-521-111 non-marine applications alike. Fax 44-1-794-517-779 We have been encouraged by the resurgence in amateur boatbuilding over the E-mail: [email protected] last ten years, especially in the area of paddle sports. Many people have cut Australia and the Far East their teeth on small craft and are feeling ready for a more challenging project. ATL COMPOSITES Pty. Ltd. If you have built a kit kayak or stripper canoe and are planning that next boat P.O. Box 2349/Southport 4215 project, this is the primary source on the techniques and materials needed to Queensland, Australia build any wood/epoxy composite boat, no matter how simple or complex. www.atlcomposites.com As we have shared in these pages for over twenty-five years, epoxy composite technology is versatile, durable, and empowering. This book grounds you in Phone 61-755-63-1222 the many techniques that allow you to build just about anything you can Fax 61-755-63-1585 dream up. If your dog-eared, shop-worn copy of an earlier edition hasn’t E-mail: [email protected] been returned by that friend who borrowed it, here is your chance to replace New Zealand it with an up-to-date expanded copy. ADHESIVE TECHNOLOGIES LTD. The 5th Edition of The Gougeon Brothers on Boat Construction is available 17 Corbans Ave./Box 21-169 through WEST SYSTEM Dealers or contact West System Inc. at 866-937-8797 Henderson, Auckland, New Zealand (toll free) or visit westsystem.com. Hardcover, 406 pages. Price: $36.40 US Phone 64-9-838-6961 plus shipping. Fax 64-9-836-4849

Epoxyworks online If you are a new subscriber to Epoxyworks or haven’t dili- clicking on ‘Articles by Subject’. Articles are arranged gently saved every back issue in a three-ring binder, you under Epoxy Techniques & Materials, Boat Repair & can find issues going back to Epoxyworks 14 (fall 1999) at Restoration, Boat Construction, Epoxy’s Non-Marine www.epoxyworks.com. You can also click on the Uses, Readers’ Project Gallery, and the Project Directory. ‘Epoxyworks Magazine’ tab on the westsystem.com site. We hope to add older issues over time, while continuing Browse back issues or find articles on specific topics by to add the current issue twice a year.

Number 23, Spring 2006 25 Sign maker Bill Boudreau of Maria, Que- bec, uses WEST SYSTEM® epoxy to build conventional laminated cedar signs like these below. He also uses epoxy for projects that go beyond conventional sign making—like this 15½' guitar and an 8' tall tooth. The monster molar was built of wood, chicken wire, insulating foam, fiberglass, and epoxy. It’s finished with polyurethane paint and has held up very well under conditions of extreme cold and a salty environment.

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