I've been learning to TIG weld and one of the tricky parts to master is feeding the filler rod with my non-dominant hand. It's been a while since I've done the challenge, so I thought I'd see what I could rustle up in way of an automatic rod feeder using just components from the TechShop bin wall.
Step 1: Raid the Bin Wall
For you non-TechShop members, the bin wall is a library of broken junk, odds and ends, and random components donated by and available to general use. The Bin Wall Challenge, hereby designated, is to see what you can jury rig together without resorting to outside sources.
Step 2: Feeding Mechanism
I'll need something to feed the filler rod into the pool of molten metal. Hmm, an broken fax machine/printer thing. It had some kind of paper cutoff mechanism, but I think it'll be much happier feeding my tig rod.
Stretch out some tension springs, bend the ends around, attach them to the sled and I've got a wire holder.
Step 4: Housing and Speed Control
Now, I'll need some sort of housing. Preferably with variable speed control. Sounds like a job for a broken impact driver!
Step 5: Check the Wiring
Make sure everything works as I expect electrically. Nice bonus, impact drivers are reversible via thumb switch. No additional components required.
Step 6: Create the Circuit
Solder the relevant components together. The little circuit board was in the charging base. I didn't use it initially, but it assists the direction reversing procedure, so I re-added it.
Step 7: Brutalize the Case
The drive assembly is larger than the drill body, so I need to make some space. And a mess.
Step 8: Assemble Housing and Drive Assembly
Step 9: Add Heat Shield and Wire Guide
Took a piece of scrap and knocked some mounting holes it in. Could have used the drill press, but that would have been less MacGyver-y. Took a filler rod, dipped it in a bit of Dykem Blue, and fed it through the mechanism to figure out where the guide hole should go. One hammered nail later, I've got a rod guide.
Step 10: Final Assembly
Add the heat shield, stick the electronics up the handle, add a battery and we're good to go!
I made it at the TechShop http://techshop.ws/
Step 11: Time to Start Welding!