How does this work?

[Roy Lindberry]

In an antique store in Port Townsend, WA, I ran across this chain drill. But I'd never heard of one before and couldn't even figure out how to work it. But it sure was interesting.

Anybody know how it works?

It is a Red Devil automatic feed #2012. I found a couple of ads for it via a google search, but that is all.

Oh, and sorry about the picture quality...they were taken on my 5 year old, .125G phone, so....

[Brett Robson]

I could be wrong, but I think the chain is wrapped around the beam or post you're attempting to drill into. When the drill is operated, the chain is continually tensioned which draws the bit into the material.

[Dan Andrews]

Roy, I can't enlarge your pictures so I can't see it as well as I would like. You will need to thread the inner spindle and outer threaded tube into the cast body (red) part of the chain drill. What should happen is that you chuck up the tang at the top of the threaded spindle in a brace. Put an augar bit in the chuck that is part of the chain drill, then wrap the chain arround the timber you plan to drill. Hook the chain in the bracket that sticks out on the other side of the chain drill. As you rotate the brace the inner spindle rotates the bit and the bracket that the chain is fastened to is drawn upwards by the outer threaded tube The threaded tube is driven at a much slower rate by a cog on the upper ring below the tang. In summary, the bit speed is the same as brace rotation speed via the inner spindle. The feed rate is at a slow rate due to the threaded tube being rotated maybe 1/8 of a turn for each revolution of the brace. My Goodell Pratt has guide rods that go from the upper ring thru the cast body that the chains are fastened to. These rods keep the chain holding body from rotating and twisting the chains up. I can't tell if your drill was built the same or not, or if it is complete. If you can post larger pics with close up shots it might help in determining if yours is complete and how to assemble it if it is different than mine.

[Roy Lindberry]

Thanks for the info Dan.

I didn't buy it, so I can't take more pictures. This was simply an item of curiosity to me and my dad.

[harry strasil]

Some models have a friction drive that automatically keeps tension on the drill bit much like a drill press, others have a manual drive that you must keep adding pressure as the bit cuts. They are mainly for using twist drills when drilling metal. The model I have has no chuck, its made for use with silver and deming type shank bits.