DIY - How-to: slotting a tiny screw ?

[De Soto Frank]

I am trying to fabricate a new pivot-bar screw for a Columbia #6 Grafonola soundbox.

I actually matched-up a machine-screw ( # 2-56 ) at the local ACE Hardware, and found a nut in stainless-steel. The only bit I could not find is a "split" lockwasher.

The screw is a "socket-head" cap-screw, which uses an allen-key. I was originally planning to cut-off the socket-head, then cut a screw-driver slot across the end of the screw.

Then it struck me... what on earth am I going to use to cut the slot, which should be between 3/128" and 1/64" ?

Ordinarily, I would use a cut-off wheel in my Dremel, but it is way too thick, at 1/32"...

Any suggestions ?

[Henry]

Frank, two suggestions:
1) 2-56 is a *very* common thread size in model railroading, and screws should be available at any good MR hobby shop, along with nuts and washers.
2) to cut a narrow slot, as you said, the emery cutting wheels are 'way too thick. Instead, try using a diamond impregnated steel cutting wheel; these are available at Horror Fright. They are much thinner.

[De Soto Frank]

Henry,

Thanks for the suggestions... we have a Harbor Fright, so that should not be a problem...

The model RR supply, might be a little more challenging, but the guys at Scranton Hobby might come through...

[Henry]

Scranton Hobby is one of the big ones, Frank! I'm sure they can set you up (almost said "scr*w you" ). They should have plenty of 2-56s in different lengths and head shapes, maybe just in brass, but they may have them in other metals (and nylon) also. Good luck. If you can't find what you need, let me know. I may have some 2-56 in the parts drawer. They're used in Graflex cameras, too.

[De Soto Frank]

Henry,

Thanks for the suggestion on the diamond-wheel from Harbor Freight.

Picked-up their 5-pack for the Dremel, and successfully created a pivot-screw for my Columbia sound box. The Diamond wheel is just a tad thicker than the original slot... if I can figure a way to dress the grit off the sides of the wheel and create a "safe" edge (like on a file), it'll be perfect.

Tomorrow I'll see if Scranton Hobby has any lock-washers.