Taiwan belt driven lathe threading gear calculator

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.


Junior Member
Oct 13, 2011
Reaction score
I have one of these belt driven Taiwan made lathes http://www.lathes.co.uk/taiwan/ - sold under many different logos/brands. The range of threads that are able to be cut as shown on the threading tables is quite good but there always comes that one time that a thread comes along that is not listed in the supplied tables. In my case I wanted a 1.75mm pitch which is very close to 14.5 TPI neither of these is listed on the supplied tables, an hour or so spent with Excel and I came up with this handy calculator, I played around with various combinations of gears that came with the lathe and settled on a combination that while not exact did give a very low error of .0045mm per turn. My lathe has an 8TPI lead screw and was supplied with the usual 120/127 metric translation gears plus 2x40 1x46 1x32 and 1x30 tooth gears, to use the spread sheet simply enter combinations of the gears you have into the cells shaded in green, (don't forget to press enter) and look through the tables to find the closest match possible - the 2nd and 3rd gears will always be either 120 or 127 teeth.
A word of warning, none of the cells are protected or locked so it is possible to alter the contents of any cell and screw up the calculations so best thing is to stick to the green shaded cells only.


  • Lath gear and thread calculator.xls
    31 KB · Views: 91

Latest posts