Friction thread

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Mr Ron
Posts: 2126
Joined: Tue Dec 22, 2009 12:36 pm
Location: Vancleave, Mississippi

Re: Friction thread

Post by Mr Ron »

Harold_V wrote: Thu Feb 17, 2022 4:44 am

If you wish to achieve properly sized holes when drilling for tapping, I suggest you double drill the holes. Start with a twist drill that is a couple sizes smaller than the target diameter, then open the hole with the desired drill. It's highly unusual for that procedure to yield an oversized hole.

Use caution when drilling some of the copper alloys, as the drill tends to self-feed when opening the hole with the second drill.

When working at Sperry Utah, we were required to double drill all holes, to assure proper size.

H
Great advice! Thank you.
Mr.Ron from South Mississippi
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