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Mast Tuning a Catalina 25 by Bill Holcomb

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Mast Tuning a Catalina 25 by Bill Holcomb The Technical Manuals were produced over a period encompassing the 1970s, 1980s and 1990s. As such, solicitations for updates are no longer being accepted, and the manuals are offered to Association Members as a courtesy by the Catalina 25/250 National Association. Special thanks go to Bill Holcomb for making these copies available for our use. The 2004 – 2005 Officers Catalina 25/250 National Association 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1 6 17 18 19 20 21 22 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Mast Base Organizer Skippers who want to modify their halyards and other lines so that all (or some) are lead from the mast base back on the cabin top for single handed sailing and for ease of handling often use stainless steel plates with attachment holes for shackling blocks. Two sources of these plates are: M&E Supply Company 1-800-541-6501 And Bill Henshaw 111-SW 16 St, Southport, NC 28465-7308 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Bill Holcomb wrote the following article on behalf of Mike Leyden and other skippers thinking about changing their swing keel to the new wing keel. Mike Leyden's Wing Keel Installation by Bill Holcomb During his fall haul-out, Mike Leyden didn't get his Catalina 25s keel fully retracted before the boat settled onto the trailer. The crunching sound that came from the keel trunk as the boat settled was alarming to say the least. Mike assessed the damage and found that the cable attachment fitting on the keel end of the cable had "flopped over" rather than finding its way into the cable hole. The resulting damage to the keel trunk was enough to convince Mike that he wanted to change to the wing keel by using the retro-fit option that is offered by Catalina. Mike and I made plans to install the new wing keel "sometime" in the spring. And, on the weekend of March 26/27 we did just that. What follows are some thoughts that Mike and I have following the installation: First of all, Mike had an almost perfect facility to do the work in. He works at a medium sized machine shop that has several overhead cranes. These cranes made moving keels and lifting the boat much easier than would have been otherwise possible. The cranes also made positioning the boat over the keel trunk (and the holes we'd drilled) very easy. The boat could be moved a little ahead, or to the right, or a little down at the bow, etc. The arrangement that Mike devised was to use two overhead cranes, one to lift the forward part of the boat and the other to lift the aft half. He prepared a nine foot long "spreader" bar to keep the 4 inch nylon straps from exerting too much pressure against the sides of the boat, and also fashioned two connecting straps to keep the lifting straps from slipping toward either end of the boat. Second, after you've received the keel, bolt hole template, resin, fiber-fil, etc.; think, think, think. What are the steps that you expect to go through, and in what order. Things like: A - Bracing the old keel so that it won't "flop" over. B - How will you lift the boat off of the old keel. You need to be able to lift the boat up about two and a half feet altogether. 23 C - Where will you put the old keel, and how will you get it there after it's been unbolted from the boat. D - How will you get the new wing keel under the boat. E - Do you have a long enough drill bit to drill the six 3/4 inch holes for the keel bolts. And, do you have a long 1/4 inch and 1/2 inch drill bit to drill a pilot hole and second hole before you drill the 3/4 inch final hole. F - Do you have a method for "sanding" off all of the old bottom paint that has been painted on the bottom of the boat and in the keel trunk. This was the hardest single job in the whole process for us. G - How will you make sure that the boat is lowered onto the keel bolts without a "near miss" and subsequent damage. H - How will you stir the fiber-fil (the bedding compound that makes a water-tight seal between the keel and boat) and its hardener. The fiber-fil has the consistency of green tooth paste and needs to be thoroughly mixed with hardener to set up correctly. I - What kind of hole in the cabin floor will you cut and how will you cut the holes so that you will be able to put the washers and nuts on the keel bolts. And, of course, how will you want to finish the hole in the cabin floor after the keel is bolted to the bottom. J - How will you "fair" the junction between the flange on the wing keel and the bottom of the boat. What do you want this part of the boat to look like when you're through. K - Will you need to drill new holes in the trailer bunks support pieces to accommodate the taller keel. Well, you can see that the 5 "P's" (Prior Planning Prevents Poor Performance) really come into play with this project. For us, everything went pretty smoothly. With the two cranes ready, Mike unbolted the old keel hangers. The keel was resting on the trailer in its normal "travel" position. Mike had also made an extra brace to keep the keel from flopping, and had already removed the keel cable winch from inside the boat. We then lifted the boat straight up about a foot or so. Mike pulled the keel cable out of the hole and we used a forklift with a ball on one fork to move the trailer forward and out from under the boat. We now used a boom-crane to lift the old keel off of the trailer, and then positioned the trailer back under the boat. One little surprise that we had when we lifted the boat off of the old keel was that we had not gotten the slings just right and the boat tilted a bit when lifted. When we lowered the boat back onto the bunks to sand the bottom, it was necessary to re-position the slings so that the boat would lift straight up and not tilt. This took a couple of tries lifting the boat off of the bunks to get the slings just right. Now Mike loaded the old swing keel onto the forks of the fork lift and we took the keel out into the yard and deposited it on a couple of 6 X 6s. Mike says that if anyone wants the keel that you can have it for free if you pay the freight to haul it home to you. It's in very good condition. Back inside, we lowered the boat and began the work of "sanding" the bottom paint from the keel trunk and from about six inches of the boats bottom around the keel trunk. As I said, this was the toughest single job. To sand the inside of the keel trunk Mike used a circular "Scotch- 24 brite" type of pad that rotated on the end of a 1/4" die grinder. He wore out eight or nine of these. A circular sanding pad for a 4" sander with 6" discs (without a backing pad so the disc would flex) was used for the boats bottom. We had thought that 80 grit paper would be more than enough, but quickly found that the 10 or so layers of bottom paint were so tough that 24 grit was all that would really do the job. Boy were we a mess, especially Mike. Throughout the sanding operation both of us wore respirators. The little white cloth masks would not have been enough with all of the fine dust that the bottom paint made. When the sanding was done, we cleaned off the sanded areas with an air nozzle and then with acetone. Now it was time to mark and then drill the bolt holes. We used the template that Catalina supplied. It is a fiberglass template that comes fitted to the new keel and has the bolt holes in just the right position. The template has a hump that fits into the keel cable hole. This anchors the template and makes marking and drilling the keel bolt holes an easy job if your drill bits are long enough. Mike ran the drill while I lined him up vertically from the side of the boat. The 1/4 inch drill bit was long enough to drill through both the top of the keel trunk and through the cabin floor. That way, we could see just where in the cabin the floor needed to be removed. Once the 1/4 inch pilot holes were in, we drilled the holes out to the recommended 3/4 inch size. This done, we both got inside the cabin and used a hole saw to cut holes in the floor over the bolt holes. Mike has a dinette model, so two of the holes were under the aft seat. One surprise that we had at this point was that the fourth hole aft was too close to the forward side of the aft seat. This meant that we had to use a jig-saw to cut an opening for the hole-saw.
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