Re: screw centers, etc.
Arch
>Georg, Just one of the many opinions you'll get re these fittings, all are valid for somebody:
A dead cup center is useful but not essential as a drive that will slip and prevent damage if there's a catch or an excessive cut. A revolving cup center is useful in the tailstock to prevent splitting the stock. Both are useful and worthwhile, and the cheaper ones are ok.
Opinions differ more about screwchucks than cup centers, same with pinchucks and cup chucks. You should either make a proper single screw chuck from a lag bolt, etc. (there are many sites for info) or buy a quality screw chuck (good steel with sharp, deep threads) which will cost more than $35. A single screw or multiple screw chuck (faceplate) fixes or limits adjusting the orientation of grain, knots, etc. and requires drilling holes. A quality screw chuck does allow freedom from tail support and perhaps easier making of a tenon or dovetail, but both can be made with a tail center in place.
For the initial preparation of a rough bowl blank, I like the security of a tail center and the alignment options of a spur drive. A large spur drive can be bought or made using sharpened short bolts thru a faceplate. Some find a two spur center is best for accomodating a bark or rough surface. Like a dead cup center, it's a useful adjunct but not a necessity.
If the piece is to be turned to completion without reversing to a scroll chuck a quality screw chuck is useful, but no more than a faceplate or much more than a pin chuck.
Finally, a grain of salt is a very useful tool before taking this advice for spending your money.
Turn to Safety, Arch
