Thread: Forming tap
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Bob Engelhardt Bob Engelhardt is offline
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Default Forming tap

On 3/21/2017 12:11 AM, DoN. Nichols wrote:
My lookup shows 4.4mm (usually metric sizes for roll taps for
imperial screws. That works out to 0.1732", while the #16 is 0.1770" so
the thread will be a bit poorly formed.

Good Luck,
DoN.


Ummm ... these are Balax taps and this Balax page shows that a .177
drill will give a 70% thread.
http://balax.com/products/thredfloers/12288-000

I'm not used to thinking about threads in percentage terms, but 70%
sounds pretty good to me.