27 tpi

[Wagon173]

Is this possible on a harbor freight mini lathe? I'm not a threading guru and it isn't in the manual, but I figure maybe it's because it's not a common pitch. Is there a way to do it?

 

[chucketn]

Using LMS Change Gear Calculator, here:

http://littlemachineshop.com/Reference/change_gears.php

I find it is possible, with gear combo 20-60-80-45, or 40-45-40-60, A-B-C-D respectively.

Chuck

 

[Wagon173]

Thanks chuck! That was awesome. I had to bookmark it. I never thought to look for a threading calculator. I suppose it makes sense as they have calculators for everything else lol.

 

[chucketn]

There are other calculators, both online and downloadable programs, but the LMS one has never let me down.
It even gives good results on the metric threads. I turned and single pointed a copy of the spindle thread on my 7x14 to make a spider using the gear combo from that calculator.

Chuck