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deltap
01-18-2007, 07:16 PM
I would be thankful for any opinions on how to complete this simple part. 2" long piece of 5/8 round 316 ss drilled end to end .228 dia. on center. Start at one end and taper from .260 dia. to .600 dia. 1.500 in from end. Next taper down from .600 dia. to .260 at other end of bar. Now for the hard part. Saw .075 slot lengthwise from outer dia. to drilled center hole. I don't know how to hold a piece tapered on both ends in the mill vise.Could one drill and cut long taper in lathe, move to mill and saw the slot, and then part off short taper on the lathe? Or should I bore the long taper in a piece of square stock, secure part with grub screw inside of square stock and mount square in mill vise for cutting slot last?

LES A W HARRIS
01-18-2007, 07:43 PM
deltap, soft vise jaws, with soft 0.228" dia pins, tighten vise, clamping part endways in the vise. Saw mounted on horizontal C/L, cut into soft jaws & pins, producing slot. You may have to put a dummy part at the other side of the vise to equallize clamping pressure.

Rusty Marlin
01-19-2007, 11:01 AM
start with part 4" long.
drill hole, may need to make a gun drill to keep it centered. Mount beween centers and turn tapers, and true up ends so they are concentric to bore leaving them over size.
hold part in vblocks on sacrifiacal ends and cut slot. Cut off ends with saw and dress part to length by hand with piloted counter bore tool.

Evan
01-19-2007, 11:57 AM
Use two 1" thick blocks of mild steel (1" sq key stock) and drill 3/8" holes in them. Dress a conical 1/4" shank grinding stone to approximately match the tapers and taper the holes or just turn the taper in the holes on the lathe with a small boring bar. You don't need to taper the entire hole, just a small amount will do, like a high angle countersink.

Place blocks on part at each end and clamp. Cut through the blocks and part. You may need to jack the bottom of the blocks apart in the vice to hold the work piece above the jaws.