Hi all,

I was trying to calculate the clamping load from a vise based on the leadscrew TPI. All of the calculators I can find online use the equation P = (KxD)/T where:

-Techshop

So, why doesn't the pitch of the screw come into play? Surely a 3/4"-5TPI Acme thread takes way more torque than a 3/4"-20 screw. Yet the formula does not account for this, and so I do not really trust it. Advice? Thanks.

I was trying to calculate the clamping load from a vise based on the leadscrew TPI. All of the calculators I can find online use the equation P = (KxD)/T where:

• T Target tighten torque (the result of this formula is in inch pounds, dividing by 12 yields foot pounds)

• K Coefficient of friction (nut factor), always an estimation in this formula

• D Bolts nominal diameter in inches

• P Bolt's desired tensile load in pounds

• K Coefficient of friction (nut factor), always an estimation in this formula

• D Bolts nominal diameter in inches

• P Bolt's desired tensile load in pounds

So, why doesn't the pitch of the screw come into play? Surely a 3/4"-5TPI Acme thread takes way more torque than a 3/4"-20 screw. Yet the formula does not account for this, and so I do not really trust it. Advice? Thanks.

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