UNC to metric

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Gary

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Can anyone tell me which If amy metric nut will fit a 1/2-13 UNC thread?

Thankd
 
bugbear":23adqdd9 said:
UNC - 1/2-13

So - 12.7 mm major diameter, 1.9538mm pitch

A metric thread chart shows that the OD jumps from 12mm straight to 14mm, so Im afraid the answer to your question is "no".

http://mdmetric.com/tech/M-thead%20600.htm

BugBear


Yeah I wasn't sure that's why I asked

Is it therefore possible to tap a 3/8-16 thread to make it 1/2-13?
 
Drill out the 3/8" thread with a 27/64 drill and then tap with the 1/2-13 UNC. Metric drill bit would be 10.7mm (a touch tight) or 10.8 (a touch loose) if you can't get you hands on a 27/64" bit.

If you are going to drill out the thread then why wouldn't you just go to a metric size that you have readily available rather than stick with the UNC?

Pete
 
The quick answer is I want to fit some kreg casters and their thread is 1/2-13 UNC.
 
Thanks for that. Didn't even know that place as there. I could walk there from work.
 
Unc inserts aren't cheap (relatively speaking)- I just bought some 1/4 from eBay but even if they are a pound each they would be cheaper than other solutions, other than possibly epoxy inch in a nut.
 
I've ordered a sample. Maybe I can find three other to do the same. :)
 
Sorry to ask another stupid question.

If the current thread is 3/8-16 can this be drilled and re tapped so I can fit a 10mm bolt?

I'm not sure having looked at some figures.
 
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