Author Topic: metal lathe thread dial  (Read 353 times)

Offline bert4255

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metal lathe thread dial
« on: April 10, 2017, 05:19:36 PM »
I would like to make a thread dial for my lathe. it is a large lathe has a 49" swing, nt that that matters. How do i determine how many teeth the thread dial needs in relation to the lead screw. Is there a ratio? I want to do imperial threads.

Offline RussellT

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Re: metal lathe thread dial
« Reply #1 on: April 11, 2017, 04:58:03 AM »
I think we need more information.  Is the lead screw metric or imperial.  What's the thread pitch?

Russell

Offline bert4255

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Re: metal lathe thread dial
« Reply #2 on: April 11, 2017, 06:58:33 PM »
I think the lead screw is imperial. I'm not sure on pitch. I'll try and find out. thanks

Offline John Stevenson

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Re: metal lathe thread dial
« Reply #3 on: April 11, 2017, 07:03:50 PM »
The gear has to be a multiple of the threads per inch.
Just guessing from the size but your lathe probably has a 4 tpi thread so the gear needs to be a minimum of 8 or better 16 teeth
John Stevenson

Offline bert4255

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Re: metal lathe thread dial
« Reply #4 on: April 11, 2017, 09:47:27 PM »
Thanks John, I will check and see what the thread count is

Offline bert4255

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Re: metal lathe thread dial
« Reply #5 on: April 25, 2017, 02:07:29 PM »
John, I'm getting about 2 1/2 threads per inch, not even 2 1/2. how do i determine if it is metric screw or imperial
thanks

Online shipto

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Re: metal lathe thread dial
« Reply #6 on: April 25, 2017, 03:05:49 PM »
Some pictures of the screw with a ruler lined up might help.
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