Tap and die questions

Old 01-28-21, 06:10 PM
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Question Tap and die questions

So I own a dumb bell but I can't find one of the screws to secure the weights. It turns out it uses an M16 1.0 45 MM. I managed to find a M16 2.0 45 MM relatively cheap but obviously that doesn't do me much good. I got a tap and die set for Christmas but have never used one before. Can I reduce the thread count required by the dumb bell and maintain the M16 size?
Old 01-28-21, 09:59 PM
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In metric world, M16 means the diameter of the bolt is 16mm, and the 1.0 is the distance between threads in millimeters. I've never tried to re-thread a bolt like that- i suspect you'd have a tough time, but it might work. If you have the proper die you might buy a long M16 bolt like the one in the link: cut the 2.0 threads off and then cut 1.0 threads in the blank part. Good luck, let us know how it goes!



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Old 01-29-21, 01:06 AM
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Can you do it yes but you will be cutting out a lot of the major diameter thread material making the thread a weak joint.

Those fine thread metrics are not used much so unless you have a dedicated fastener retailer like Fastenal around you wont find them at the local hardware store. And even then they will probably have to order.

Might check eBay!
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Old 01-29-21, 06:06 AM
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No, I would not try to convert from a coarse to a fine thread. There won't be much material left to hold. You would need to go to the next size larger bolt or... just get the correct bolt. And I don't think your thread spec is correct. I think your M16 is actually 1.5 pitch and not 1.0 pitch. If you search for that you should be able to find what you need.
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Old 01-29-21, 09:02 AM
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Also the tap and dies sets most of us diyers have are more suited for chasing threads [cleaning them up] than actually cutting new threads.
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Old 01-29-21, 01:45 PM
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Yeah I also thought about converting it to a 3/4 size bolt. Which is the next biggest US sized bolt. If I can get the right size tap I will attempt it but it will be awhile.
Old 01-29-21, 02:39 PM
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Have you checked at an auto parts store? Most have a large supply of metrics.

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