Shaper runout

[Ed Clarke]

How do you measure spindle runout on a shaper? I tried putting a 30mm spacer over the 3/4 spindle and measured 9 thousandths variation at the top of the spindle with a dial indicator. The spacer is not totally tight to the spindle ( nor can it be or you couldn't get it on or off ). I suspect this measurement is meaningless due to slop.

The spindle itself is threaded so I can't measure that directly. Any ideas on how to get an accurate measurement?

I'm checking runout because I'm getting significant vibration with a very heavy cutter. I suppose the cutter could be out of balance also. The cutter is a Leitz jointer - 3 inches in diameter and two inches high with two blade inserts held by gibs.

[George]

My shaper has flat threads, like a tablesaw arbor. I suppose something to spread the load across threads, like a metal feeler between gage and indicator might do. Either that, or something milled, like an adapter bushing or bearing, something where it's designed to concentricity rather than thickness, like a spacer. They fit pretty tight, because you have to keep them properly aligned or wedge them on the spindle.

I'd start out by pulling the spindle, cleaning the taper, and reseating before fiddling much, though.

[Jim Behning]

We had a shaper that I think had a 1 inch shaft that was bent. It also has wollered out bearing surface. It was sent of to the machine shop to have the bearing surface built up and turned. I think the shaft still was wobbly at the top so the new cutter was mounted lower. It was much quieter when the cutter was not off center and the shaft was not violently vibrating. We used this to round over 3/4" yellow pine with a power feeder.

You might send the cutter off to the machine shop for a balance check. You could also get them to turn some collars with .75" id and accurate od to measure the shaft for runout.

Is the cutter holder round? Remove the blades and measure runout there. Cutter holder has to fit snug to the shaft.

Ed Clarke wrote:

Jim B.

[Duane Bozarth]

George wrote: ...

Just as a btw, fwiw I believe those are Acme threads...