1. I never alter the height of my Tool Rest
All lathes that I know of have a vertically floating Tool Rest. Most of you also have no need to alter the height, and yet every time you alter the rest position relative to the slide you probably alter its vertical position. What a nuisance I find it to be, having to recheck the height of the rest every time I move it! What about fixing a piece of steel tube over the Tool Rest post to form a collar or packer between slide and rest, thus keeping the height fixed. A bit of trial and error will soon determine the right height for you, but about 4mm below centre height is a good start. Some purists would say that you need to alter the height constantly according to the tool you are using. I say keep your rest back from the work a little bit and raise and lower the handle to put the cutting face exactly where you want it.

2. Tool Rest Top Smooth
 If you want to make fair curves, the top edge of your Tool Rest must be absolutely smooth and without any sharp edges. With a file, dress the bearing edge and then sand with silicon carbide paper. Similarly of course, the shanks of your tools should be polished.

3. Modifications to Tool Rests
a) Top edge or bearing surface. Usually the top is flat across as in ‘A’ so that when the gouge is level it is in close contact to work - but drop the tool handle down and your bearing point moves back. Remedy - file or grind the bearing surface to ‘B’ so that then the bearing surface doesn’t alter it’s position relative to the work as the tool handle is raised or lowered.

b) Inside lower corner of the Tool rest - you don't need it - in fact it’s a jolly nuisance, so chop it off! With this corner off you can quite safely fit the tool rest inside small bowls or goblets etc. Don’t forget to file all the all the corners smooth to be user friendly.