George,
What are you thinking of making with your new machine and 4th axis?
Keeping it simple now,decided to use the chuck and spindleon a home made lathe.

Got the motor(2500rpm),got the pullys...one 50mm V type for motor shaft,one 4" for the spindle...will worry about gearing when its up and running? the speed contoller is a simple one for now ie it came off a defunctn router.
The bed will be 25x25x3mm box section,Ifigured its not worth making it big ie 600x250x250mm should do it.
Ordering the toolpost and tail stock from www.littlemachineshop.com

Why is it that you can get anything and everything under the sun from the states and you try here in the UK and its like looking for a needle in a haystack...really pi**es me off trying to buy stuff over here.