Still a WIP, but someone swung by my channel and mentioned folks over here might be interested
I picked up a cheap leather patcher machine (also known as a cobbler's machine), which is a cheap knockoff of Singer's 29K machines. They are designed for patching shoes, bags, patches, etc and are most often used on the street for quick repairs. The machines are super crude castings and roughly machined parts, but get the job done. Big hand crank, beefy needles, long arm to fit deep into bags/boots/etc.
I'm adding a motor to mine, and then will clean up the casting/machined parts to make it a little more polished. I'm using a brushless "hoverboard" hub motor and coupling it to the patcher via a v-belt. Fabricated a v-belt pulley for the machine out of tooling plate aluminum, and a small adapter to mount a cast pulley to the motor. The motor was chosen because it's a low KV motor (~600 RPM max) and very torque'y for it's price (10-12NM based on other hobbyist's tests). They run $30 new on ebay, $15 used. Hard to beat that price
The remaining work is to mount the motor and build a replacement stand (since the tripod that comes with the patcher is useless). I don't currently own a lathe, so there were some...uhh... creative arrangements to fabricate a v-belt pulley on a milling machine
(Apologies for audio on this first video, things went a bit wonky in post-production and I didn't notice in time)