Older Diacro #1a question

Dumpster_diving · Feb 12, 2020

Picked-up an older (much older) Diacro #1a bender and need to remake the post that threads into the central hole in the top platen. Was wondering if anyone knows the thread size/pitch of that center hole.

I believe it's imperial and not metric (several of the other bolts are imperial).

The female threads the post screws into look close to 1/4" (maybe a hair larger). But not 1/4" x 20 tpi (I checked that).

I'm thinking possibly 1/4" x 24 tpi (but I've got nothing convenient to check it against).

Much appreciated in advance...

James H Clark · Feb 12, 2020

Turn a piece of wooden dowel to a diameter that is about .015" bigger than the minor dia. of the hole and about 1" long. Then screw it into the hole and back out. This will tell you the minor dia. and the pitch of the thread. Job done.

JH

L Vanice · Feb 12, 2020

There is an old machine screw size, 14-24 or 14-20, that is .242 inch, a little smaller than 1/4 inch.

Larry

Dumpster_diving · Feb 13, 2020

Thanks both of you. I love the soft dowel idea. I’ve got pitch gauges, just couldn’t see them inside the bore. That’s a perfect solution.

Dumpster_diving · Feb 13, 2020

James- Your trick worked great. Turned a little stub of delrin down and it threaded right in and right out. Retained enough of the pitch that it was a piece of cake to read the pitch on the delrin OD.

Larry- Turns out it was standard 1/4 x 20. Just clogged with swarf. Ran a tap in and cleaned it right out.

Thank you both!

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Older Diacro #1a question

Dumpster_diving

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L Vanice

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Cast Iron

Dumpster_diving

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