Y-Geo,

I replaced my plastic headstock gears with metal gears. There are many pros and cons on using the plastic vs. the metal gears. The plastic gears may have less running noise and could shear off if you crash the lathe but in my last 24 years of using my mini lathe have have never crashed lathe and now satisfied with using the metal gears. I did not notice much of a difference in the sound levels using plastic vs. metal and it may depend on the lubrication. I use a high pressure gear grease in the mini lathe headstock with the product "Dart LUBE CMD Extreme Pressure Lubricant" (see https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1 ) and it seems to make the gears run with little noise. Also see the discussion at http://www.homemadetools.net/forum/r...ad-lathe-16967 .

Good luck with your mini lathe improvements. I think it is a very worthwhile endeavor and can see the difference in the higher quality machined parts.

Regards,

Paul Jones