MIllers Falls/Goodell Pratt restoration help

[David Wadstrup]

I've turned a couple of side knobs to replace the missing ones of my MF No. 2 and GP No. 5 hand drills. And I've bought some 5/16" - 18 threaded rod. It seems, however, that the pitch isn't appropriate -- I'm able to screw it in about 1/4' before it starts to bind. I've done a bunch of internet research trying to find what the correct size/pitch is, but I'm not getting the definitive answer I'm hoping for. I've read about a couple of people guessing at 5/16" - 20, but they seem to be just guesses. Also, it doesn't seem that this pitch is currently made. McMaster sells a 5/16" - 24 which I could try, but I'm reluctant to spend $8 on shipping a $2 purchase without knowing if it's going to be an improvement. I've also read that an M8 - 1.25 might be close to what is needed, but again, this seems like a guess. Anyways, can anyone tell me what the correct size/thread is needed for the side knobs of these drills(they're both the same.)

Any help would be greatly appreciated. Thanks fro reading!

[Jim Koepke]

Hi David, It is a 5/16-20. If needed a die can be purchased at > https://www.victornet.com/subdepartm...-1-2/1350.html

They have a $25 minimum order. It is an easy amount to get to with a few taps or drill bits.

If you plan on doing restoration on old tools it is real handy to have a thread gauge and a screw size gauge.

jtk

[David Wadstrup]

Jim,

I somehow went down the rabbit hole of thread and die research and forgot to thank you. I'm sorry it's taken me so long. Thanks so much for passing along the advice and tool recommendation! Knowing the thread definitively is a big help!

David

[Jim Koepke]

You are welcome David.

jtk