Renovation: Sewing Seats By Dennis Wolter o there are your seats – all fixed results in too many stitches up, foamed, painted and sitting per inch and, since each Son the work bench staring at you stitch is a hole, you will right in the face. What to do next? Not to end up with a very weak worry, you have options. Here’s my plan. seam much like a perforat- I will explain how we sew seats here at ed check in a checkbook; it Air Mod, and teach the do-it-yourselfers will eventually tear loose. how to sew the seats and side panels. If This type of work simply you can do seats, side panels will be a cannot be done on a home piece of cake. I plan to deal with Cessna sewing machine. headliners, all three types of them, as a What you need is a walk- separate article. ing foot, needle feed com- Of all the various tasks involved in mercial upholstery sewing aircraft interiors, I think the most skill machine. They are quite demanding one is definitely the sewing expensive if purchased of the seats. Next time you’re at Osh- new, but can be acquired kosh, check out the interiors in some of used for $500 to $700. the homebuilts and you will see some Make sure you buy an up- beautiful metal work, painting, instru- holstery machine where ment panels and side panels, only to be the upper foot and needle disappointed by poorly sewn and ill-fit- and the lower foot move ting seats. For the do-it-yourselfer, don’t simultaneously to advance expect total success on the first try. This the heavy material through The business end of a walking foot needle feed machine. whole sewing process can be a difficult the machine. Commercial All this stuff moves with the material being sewn. skill to master. Be prepared for some re- dress and drapery machines work, but if you stick with it you’ll be look very much like an up- amazed at how much you can accom- holstery machine, but do plish. not have this feature and For many of you the sewing part of will not do the job. The the interior renovation process may be two most common walk- beyond your technical capability, time ing-foot, needle-feed allotment, or inclination. In this case, I machines available for would suggest checking out some car this purpose are a Singer show and air shows, find out who in 211 and a Juki LU562. your area is doing good car interiors, For those of you or ask home builders who helped them handy enough to attempt with their interiors. Believe me, these this part of the inte- hot rodders and home builders will rior renovation, the rest know. Employ these artisans to sew and of the tools and talent mount your seats and side panels. needed are pretty obvi- If you are going to do this yourself, ous, and will be covered here’s how it’s done. First, you will need as we progress through a proper sewing machine. It is unrealis- this series. If you live in tic to plan on using your home machine. a larger town or city, you Home sewing machines have only one probably have an uphol- foot to advance all those thick layers of stery supply house close material through the sewing head. Also, to you that can be a good the lift-and-stroke of these home ma- source for equipment and chines is too short, making it difficult, Eight Layers of finish material, backing foam, and fab- if not impossible, to pass those materi- (See: Renovation, pg. ric. Note the nice wide stitches - strong and durable. als through the sewing head. This also 36) www.cessna.org 35 Renovation a yard of non-aircraft scrap (Continued from pg. 36) vinyl or cloth for practicing difficult stitching or fitting information. before you use the more ex- In this month’s install- pensive treated aircraft ma- ment, I’m going to show you terials. A penny spent can be the techniques we use to cre- a dollar saved. ate ergonomically correct, We usually buy about aesthetically appealing and five 40-50 square foot hides durable seats. Some of the of leather for a four-place steps we incorporate into our Cessna interior, obviously seats could be left out and the more for a six-place air- seat will still look darn good plane. This allows for a 10% at delivery, but over time you loss for cutting out leather can end up with premature defects and the half-hide failure or deterioration. If you leftover allowance for pos- are doing this work yourself, sible future repairs. If the be perseverant, stick with it interior is to be done in a and try to follow all of the Patterns being fabricated on a Cessna seat back. combination of fabric and steps. I’ll give you some vinyl we will probably order tricks as we go to help you six yards of cloth and eight attain good results. I’d like to yards of vinyl (these quan- stress again how important it tities can change depending is to use an industrial sewing on seat design and the re- machine. It is key to success. spective usage of fabric vs. Costs being what they vinyl). Barring any major are, it’s important to first mistakes, you should end buy enough material for the up with the suggested extra entire job, including some al- for future needs. Some pat- lowance for a mistake or two. terned materials may require You should have enough left additional yardage to allow over for future repairs (maybe for proper pattern alignment. a yard each of fabric or vinyl While we are on the subject and a half-hide of leather). of materials, we usually buy Aviation-approved materi- somewhere between a 12x6 als are constantly changing or 12x8 piece of carpet and and can become discontinued three or four yards of head- even before your project is liner material. completed. If you’re a nov- Efficiently laying out patterns on the raw material. The first step in seat sew- ice, it’s a good idea to buy ing is to lay out the materials. The gals in the sewing room like to make a set of patterns to help them organize the layout and cutting of materials. This reduces mate- rial loss and mistakes. Heavy paper or thin cardboard patterns are laid out and trimmed to meet the various contours of the seat shapes; use something about the weight of a file folder. Then the pat- terns are placed on the raw material in such a way as to most efficiently use the material and/or work around leather de- fects. These patterns are cut to the exact shape of the section of the seat they are to fit plus 1/4” seam allowance. This small overhang past the stitch line is necessary for the material to properly pass through the sewing machine head during the stitching process and also to 36 Cessna Pilots Association - December 2006 Top or french stitching This method involves first making a plain stitch as described in the previous paragraph, then fold the selvage or cut edge back on itself and care- fully top stitch the material on both sides and paral- lel to the single stitch seam. We apply a reinforcing tape on the back side spanning both sides of the cut edge to add extra strength to the seam. This gives a very nice looking finished appearance to the seam, but it is the least durable way to sew a seat. All of the french-stitched thread and the folded edge of the material are fully exposed to sunlight and abrasion. Cording Last, but certainly not least, is the good old corded seam, the most durable way to sew a seat. This method employs the use of cording, made by folding a 1” wide strip of finish material (usually Temporarily staple the seat together to help hold the panels during the sew- leather or vinyl) around a 5/32” foam cord that is ing process. single stitched to become a flanged cord. This cord is then placed between the two materials. Once sewn give the component strength once it’s sewn. If you sew too together, the cord provides complete protection of close to the edge of the material, the cloth will unravel and vi- the stitching and the folded edge of the upholstery material, nyl or leather will tear loose at the stitch. We also double stitch eliminating exposure to sunlight and abrasion. If, after a long the seams, and over the past thirty years have experienced no period of time, the cording begins to show signs of wear, the seam failures with this technique. Just flip the material over seam can be carefully cut open and the damaged cording re- and re-stitch the other way. placed with new. It’s a good idea for someone sewing for the first time to allow as much as 3/8” for a seam allowance. More allowance (See: Renovation, pg. 38) means more control of the stitch. Also for the first timer, there is another advantage to having a slightly more generous seam allowance. You can actually staple the More than Quality seam to help hold the several layers of material together during the sewing pro- Products — cess. It takes a little more time but it sure makes it easier. Don’t forget to pull out Peaceof Mind the staples after the seam is completed.