Interior... Where No Man Has Gone Before



I have mentioned this before in other updates, but every time I tackle a new build I try to do, or better stated, learn something new. With this build I've already done that with the headliner. A daunting task to say the least, especially when you have no experienced help and no experience yourself. That task came out not perfect, but acceptable for anything other than a "show car" which this is not.

All that said its time to launch into something entirely foreign to me..... SEWING. On my Deuce build we did most of the interior ourselves, but my wife did all the sewing and we didn't do the seat upholstery. This time she is teaching me how to sew so I can do all the upholstery. Seats, door panels, carpet, everything. To say I'm a little anxious about tackling something this complicated and involved is an understatement. However, you never learn anything unless you try it, and I'm not going to let it beat me. So here we go.

This will take a while to complete considering the learning curve, so expect this to take two or three months... possibly more. The first thing I needed to do was learn how to use a sewing machine. My wife does quilting and embroidery on an expensive machine and she is not willing to allow a novice to mess with that one... and quite frankly I don't blame her. She does have a 40 year old Singer that we broke out of moth balls, cleaned up and I've been practicing basic stitching and some upholstery specific stitching using this machine.




Believe me there was a lot to learn especially since I know nothing about sewing yet alone sewing machines. She has educated me now to the point where I'm just dangerous enough to practice some advanced techniques on my own, like piping. You can purchase ready made piping but it may not match the color you're using for your upholstery so in many cases you need to make your own. This was made using 1/4" cord and the vinyl material I'll be using on the rest of the interior. Not bad for a total novice.




The problem with this old Singer is that its really not designed do to leather or vinyl upholstery. It's largest stitch is way too small and small stitches on vinyl or leather will just weaken the material. So the solution was to find an industrial sewing machine that is made for heavy duty use and has the ability to do larger stitches.

We looked around and found a Juki DDL 555 machine on Facebook Marketplace that was priced low enough to suit our purpose. Actually we got a smoking deal on this machine since we paid only half the going price and the machine was complete and in good working condition. Juki is just one of the popular industrial sewing machines out there, and this Japanese company has been around since the '40s. Like all industrial machines its over designed so it will last forever, and parts are readily available. They are also HEAVY.... ask me how I know. Here is our new Juki machine. I say new but this model was first produced 50 years ago, and its one of the good ones. Today's Juki machines are made in China, this one was made in Japan.




It's not fancy, but it will definitely get the job done. Using an industrial machine is not remotely like using a simple home use machine. To begin with this machine sews at 5500 stitches per minute. That is lightning fast even for an experienced seamstress. These machines are usually found in factories were people spend all day sewing blue jeans and other mass produced products so speed is a necessity. Just look up some videos on YouTube and you'll see what I'm talking about. So, how do you slow these machines down?

After doing a little research there are several ways to do this. The first is to change the pulley ratio. This is a simple procedure and just requires the replacement of the pulley on the motor from in this case a 4" pulley to a 1 3/4" pulley. Here's the old pulley followed by a picture of the new one.







This pulley change reduced the speed of the machine by 60%. So now we're down to 2200 stitches per minute. Still way too fast. Another modification that can be done is to change the ratio of the clutch bar to make it less sensitive. These machines use a clutch system to engage the motor and run the actual sewing mechanism. If you slow down the engagement of that clutch you can start the stitch at a slower speed rather than have the machine jump to full speed too quickly. This modification is done simply by extending the clutch bar by 12-14 inches. Here is a pic of the 1/8" aluminum angle I used to extend mine by a foot.




These two modifications worked pretty well, but the machine is still too fast to comfortably sew upholstery. There are still a couple other options to consider. One is swapping out the clutch motor for a "servo" motor. These have the advantage of adjustable speed settings. However, for our purposes something like that is just too expensive. So the last option is what is called a speed reducer. Basically it uses a couple more pulleys to reduce the speed even more and can reduce the speed slow enough to easily sew almost anything. In other words.... Even a novice could do it.

Speed reducers are readily available but are priced at $125 and up. That is more money than we want to spend, so the solution is to make our own. Here is a picture of what you can buy. This one is at the lower end of the price scale. I think I can make one for under $50 so why spend almost a hundred extra bucks for this one.




I'm not going to go into the fabrication of a speed reducer in this update... simply because I haven't made one yet. Although I will cover that in the next update. Now... on to what else I've done this month.

Sewing isn't all that is required to update an interior. It's just what you see on the surface. Like paint is the part you see on the outside of the vehicle, but you don't see all the preparation that made the paint look perfect. In upholstery the sewing is what you see and all the preparation work is not seen at all. So here's some of that "preparation" work.

Once the original upholstery is removed the seat frames need to be cleaned up and any repairs made to get them back in working condition. I was lucky in that my back seat frames, both seat and seat back, were in good shape. The next job is to install new burlap over the springs. This protects the seat foam and keeps the springs from "eating" their way through the foam over time. Here are the seat back and seat frames with new burlap installed.




One thing that needs to be mentioned here is the special requirement of additional burlap on the seat back. The top of the seat back that meets the package shelf needs a layer of burlap held in position with listing wires and hog rings to support the padding and keep it from falling down into the seat frame over time. Forget to do this and before long your seat upholstery will look like crap. Here's the section I'm talking about. This is just one of those little things that may not be readily apparent, but really needs to be done.




If you've never used them before, Hog Rings are the tool that holds the material on the springs. Summit Racing has everything you need when it comes to using these little buggers and they are surprisingly inexpensive.




The next problem will be to cover the seat frame with foam and the seat back with cotton batting. Yes sometimes they don't use the same material. This is one of those cases. I'll be using 1 1/2" of foam on the seat. This thickness is available but for some reason is expensive. So I'll be using 1" and 1/2" glued together to get the 1 1/2" I need. This method will save me about 50% of the cost of 1 1/2" foam. Here's a pic of the foam sheets.




Installing the foam will is a job I'll be getting to next month. I want to finish the modifications to the sewing machine first. In the mean time, here is an example of a French Seam that I'm considering using on the seats. This was done on the Juki industrial machine. A lot of modern high dollar cars use this type of stitch instead of piping. If it is backed with an additional layer of material it makes for a very strong seam.




Here is what I mean by "backed with an additional layer of material. This gives you basically three stitches to hold the seam together.




The overall design of the interior will be a modern interpretation of a Super Stock A990 design which used Dodge A100 van seats. Here is an example. This particular one has the rear seat delete option and has had a cage installed. Mine will not have a cage and as you already know, will have a back seat.




That's about it for this update. Next month we'll continue working on the upholstery, patterning and sewing techniques. Wish me luck.



Check back often for more updates...





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