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kenrinc
01-11-2007, 01:20 PM
In going through a search of turning morse tapers I came across some good info but am trying to understand a previous post:

"take another #2 taper ,reverse it ,and hold it against the part in the chuck. wrap the two together with masking tape, (two turns) and then mike both ends. Keep parrallel ! If you have matched the taper, both dimensions will be the same ! ( and it does not matter what it is!) If not, turn the toolslide towards the bigger diameter (slowly)and take another cut.
No math, no markings, No gauges except a mike . For the old timers..the value of this method is that tool centerline height becomes irrelevent."

What I do is chuck a piece of scrap, face and center drill, put the nose of a MT2 center in it, support other end with tailstock. Mic and adjust compound. Cut taper and then blue and fit with emory/file. I don't understand the masking tape comment above? My MT2s still come out with the larger side larger. I use a DTI and tap the compound to compensate by moving .001 each time but find that all of sudden the small end will rub. Argh...!

Ken-

Magic9r
01-11-2007, 07:11 PM
EDIT - failed attempt to post ascii art answer

YankeeMetallic
01-11-2007, 08:05 PM
In going through a search of turning morse tapers I came across some good info but am trying to understand a previous post:
"take another #2 taper ,reverse it ,and hold it against the part in the chuck. wrap the two together with masking tape, (two turns) and then mike both ends. Keep parrallel !"

What he is saying is that you subract the taper by reversing an item of the same taper, putting it side by side which will equal a zero taper. Rather clever.
An easier way ( I think anyway) is to but a tapered shaft from ENCO in the taper you need that has the other half a straight shaft. This works for all tapers. Set up a dial indicator horizontally in a tool holder with the tip toward the head centerline. Chuck up the straight shank in the chuck and ensure it runs true like it should. Then set your taper attachment so the dial indicator tip runs up and down ther tapered part of the shank while indicating a constant zero as it is run up and down the tapered part. Tighten the taper attachment, replace the tapered / straight shank with your work piece and cut the same taper. I bought a full set of tapers with straight shanks from ENCO at about $3 apiece that I use only for setups.
I hope I explained this well enough. I find that it work better than setting an inch/taper or degree/taper from a book, since the indicator on the taper attachment is so small you cannot get fine increments.
If it helps I can take photos of each step.

J Tiers
01-11-2007, 11:22 PM
If you have a MT2 on teh lathe it helps..... like the T/S. Then you can directly check with a DTI whether you are parallel to the taper. if not, then you have to do something else, like a center with nose in a female center on TS and male center in spindle.

First, be DEAD CERTAIN you have the indicator ON CENTER before checking against a taper on the lathe..

Then, yes, turning the compound is the way if you have no taper attachment.

Tapping it to turn it into agreement is what you have to do.

Then, once you have the thing dialed in as best you can, be DEAD CERTAIN the tool is at the same height as the indicator, which would be "on center".

You will still have to adjust, so be ready to.

If you are so unfortunate as to have a compound that has the little tapered knob to hold it, with two little setscrews, ouch. I'd rather have the two t-bolts that I have on mine, I think it is easier to adjust.

Doing the subtraction measurement is good, but the axes of the two MUST be dead-on or the measurement will fail. I find it awfully hard to keep two tapered things lined up like that. I'd rather fit it to a gage, such as a MT adapter that you blue up and check it with.

kenrinc
01-12-2007, 01:49 PM
Thanks for the helps guys. I'm still hacking it out. I've got 20 4" pieces of CRS that I'm going to just turn into MT2 adapters so I'm going to figure it out one way or another LOL!

Yankee, I think I see what he means but I still don't see how you would set the compound with that info. Two taped together centers reveresed are parallel to the c/l of the lathe so I don't see how you set the compound.


If you have a MT2 on teh lathe it helps..... like the T/S. Then you can directly check with a DTI whether you are parallel to the taper. if not, then you have to do something else, like a center with nose in a female center on TS and male center in spindle.

Are you saying measure the inside taper of the tailstock to set the compound? My DTI can't reach far enough into the T/S taper to measure that. Right now I'm just using a MT2 dead center, with a center hole drilled in scrap in the chuck other end held by the dead center in the T/S. I measure with DTI, cut and then use the T/S to blue and fit or I also have a MT2 adapter I can use. I've done 4 so far. 3 seem " O K " but a bit tight at the big end. The last one was a failure and ran out of taper so had to scrap.


Doing the subtraction measurement is good, but the axes of the two MUST be dead-on or the measurement will fail. I find it awfully hard to keep two tapered things lined up like that. I'd rather fit it to a gage, such as a MT adapter that you blue up and check it with.

The fitting is so.... "fiddly". That "marking" blue paint doesn't seem to dry and it's difficult to see where it's rubbing. Dykem seem worse. It dries but is so flaky that I'm unsure that it's not actually thick enough to throw it off.

Ken-

YankeeMetallic
01-12-2007, 04:16 PM
"Yankee, I think I see what he means but I still don't see how you would set the compound with that info. Two taped together centers reveresed are parallel to the c/l of the lathe so I don't see how you set the compound."

Don't worry we will be with you until you get it right. The use of a compound will be almost the same. Put the dial indicator in the tool holder horizontally facing the CL (Center Line) of the head. Loosen the compound and aim inward almost toward the chuck, but with the compound dial a little closer to the CL. Extend the compound all of the way out. chuck up a known taper sticking out of the chuck that you want to copy. With the tip of the dial indicator moving up and down the length of the taper in the chuck, adjust the compound, clockwise, or counter clockwise and keep moving the compound dial back and forth until the dial indicator reads zero. Lube the tapered piece to keep the dial needle from jumping around when you are running it up and down the taper in the chuck. Depending on the size of your lathe and the full extension of your compound, you may not be able to cut a full morse taper due to the tapers length. My Hardinge has such a short compound range I must use a taper attachment to make a taper as long as a Morse.
Tighten the compound and lock both axis' on the lathe so you don't accidentally move the wrong handle, replace the indicator with the cutting tool, replace the known taper with blank stock and start cutting your taper.
You will not get as smooth a finish as you would with a taper attachment because you are turning the compound at an inconsistent speed, instead of using the power feed function with the taper attachment.

If this doesn't work I will gladly post some pic's. Good luck!