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I am trying to sand a segment ring but the tail shaft will not hold the chuck with the taper. Ring is in Cole jaws and using 60 grit paper on faceplate, speed is 140 rpm . Am I asking to mutch for the taper? Sand paper to aggressive? This is a Laguna 1524 so I don't want to be cramming the taper to much with the screw.
If you haven't tried a thorough cleaning of the taper surfaces and inspection for burrs or any "gunk" that might prevent the taper from fully seating, that would be my first step.
I would clean the MT2 with a solvent such as DNA or Mineral Spirits, first.
This seems overly complicated. Mount the Cole jaws with the ring on the headstock. Cut a ¾ piece of mdf about 2 x 10. Wrap a half-sheet of sandpaper around the mdf, hold it against the spinning disk. Changing to a new piece of sandpaper takes no time.
Will this method ensure both sides will be parallel? And using the tail shaft I can stay out of the dust,I will try a 60 grit paper.Quote:
Originally Posted by James Morgan
This is a stupid recommendation / question...... do you have the tail stock advanced far enough to allow the MT to fully engage the overall taper length.
It takes quite a bit of energy to slip a correctly seated / fully engaged taper and close to fully seated tapers might as well not even be there.
Tapers are popular on lathes and especially large diameter high HP machinery. Transmitting high HP (on industrial machinery) across a shaft coupling requires either a shrink fit or a taper fit. With a shrink fit removing the coupled joint for repair / maintenance is mechanically very difficult. A taper fit on the other only requires incredibly small movement to fully dis-engage. On our lathes we install and remove components constantly so the taper fit is magic but it only has to be less than a whisker off to not grip.
mike calabrese
Mike ,I fully agree. And thanks Ken,and Paul,so I'm thinking I am not doing anything wrong but need to look at the quill on the lathe.
Just the other day I used a 3.25 forsner bit to bore out a small bowl,no slipping,but
a different situation. Pressure being put on the taper on drilling, not a lot on standing. I have a new drill chuck ordered and possibly a reamer.
Yes, it's just like facing off any surface. Of course if you have a lot of material to remove, sanding is not the most efficient approach.Quote:
Originally Posted by Tim Elett
Stupid recommendation? Perhaps. I adopted this technique from Malcolm Tibbetts, who knows just a little bit about segmented turning.
He was referring to his recommendation/question not yours.
Another approach would be to attach the sandpaper to a sheet of plywood or MDF or a metal sheet that is large enough that it sits flat on the lathe ways. Use the tailstock with a live center to press on the sheet of plywood, etc. That way, there won't be any rotational forces applied to the morse tape.
Also, once you have spun a morse taper tool enough, you are likely to have put ridges in either the two tapers.
I suppose that you could accomplish the same thing as the plywood sheet on the ways by putting a wrench or tommy bar or something on your chuck or chuck key and accomplish the same thing.
When people are drilling smaller holes using the tailstock, the tailstock chuck usually works well. But, when your drill size increases, you get closer to the point where the morse taper chuck may spin. And if you are sanding a substantial ring, say 8 inches (or more), it is like putting in an 8 inch drill or forstner bit. That applies a tremendous torque on the morse taper. Maybe if you put in a drawbar and tightened the heck out of it, plus didn't apply a lot of sanding pressure, it might hold. Or not. But you don't appear to be using a drawbar. So, what happened isn't too surprising to me.
If you want exact parallel sides, time to invest in a drum sander.Quote:
Originally Posted by Tim Elett
+1 to this.Quote:
Originally Posted by Richard Coers
I love my drum sander. Lots of folks hate them, but if you use them as they are intended to be used, there is no equal. You get parallel sanded sides.
For you original question, depending on the diameter of your piece, there is a huge difference on torque from a 3" forstner and a 12" ring. I'm sure you know you can put a lot of force with the tailstock quill. I think (my OPINION) you are asking too much for your MT2 to hold. Drum sander is the safe answer.
I have been looking for a sander used but I have other pots on the stove. I know woodmaster makes a great one,my older brother has a big 36 inch model, but if a ring comes apart I don't want to be responsible for the crash! Thanks all for the replys.
I replaced the taper and chuck and using a half round sand paper on faceplate, working better, hopefully I can find a sander somewhere.Quote:
Originally Posted by Tim Elett