Random thoughts.... If you want a longer stitch you will need an industrial. That Kenmore should have a fairly long stitch for a home machine. I wouldn't spend much money on one though. Some zz machines have a kind of long stitch but you also need a bigger needle than your home machine can drive through the needle hole. Sunbrella isn't terribly heavy. If you are only making one item you might find a beater vintage machine and throw it out when you ruin it. Or you might simply have to have an extra throat plate to replace one that gets knawed by a needle. 6 layers is not your only issue, you also have to consider how much weight you are pulling through. Most vintage machines will go through 6 layers. Thread needs to match needle size or you will be shredding. You can do it on a vintage machine but your best results will be a vintage industrial set up for heavy threads. If you buy an industrial high speed machine you are wasting time and money. Some Japanese machines came with bigger than 1 amp motors. I use a 1.5 amp motor on my ugly beater 15-75 for speed but I don't have room to ream out the needle hole on the throat plate to use a bigger needle. I got a Davis VF treadle thinking it might do heavy stuff. It will but the stitches weren't long enough to suit me. For anything that is going to take high winds you really do want your stitches long. I don't know where you live but some times vintage industrial machines come up on CL. They could be run off a home motor if it is big enough. You might put a servo motor on one. Build your won box or table for it. A guy bought a long bobbin machine from me to keep on his sailboat in case he needed to mend. It likely worked fine. If you are using sunguard thread you will need at least a 20 needle size and that is too big for your hole. The small hole will shred thread.
I'm thinking victoriansweatshop forum has a discussion of vintage industrial machines.
Last edited by miriam; 09-23-2016 at 07:43 AM.