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5C Collet Thread Specs

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5C Collet Thread Specs
EdK Offline
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#1
07-31-2013, 06:22 AM
Does anyone know what the minor diameter is for the outside thread on a 5C collet? It's a 1.238-20 thread but I can't seem to find a minor diameter for it. I know there's a formula for calculating it but that escapes me at the moment. Chin

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Mayhem Offline
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#2
07-31-2013, 06:42 AM
Take a look here ED Marv probably has a calculator programmed up already...


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.xls   Minor thread diameter.xls (Size: 15.5 KB / Downloads: 6)
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EdK Offline
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#3
07-31-2013, 06:55 AM
(07-31-2013, 06:42 AM)Mayhem Wrote: Take a look here ED Marv probably has a calculator programmed up already...

You beat me to it Darren. I just visited that thread and thought I'd post the formula for others to enjoy.

TD = MD - 0.013*DOT/TPI

where:

TD = tap drill diameter
MD = major diameter
DOT = desired depth-of-thread expressed as percentage

Ed
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#4
07-31-2013, 07:20 AM (This post was last modified: 07-31-2013, 07:25 AM by Mayhem.)
Here it is as an Excel calc:


.xls   Minor thread diameter.xls (Size: 15.5 KB / Downloads: 13)

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