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Rich Roberts
05-16-2001, 09:14 PM
I have an old Atlas horizontal mill which has a drawbar-type Morse taper in the spindle. It has been in storage for a couple of years with an end mill holder in the spindle. I tried to remove the holder in the usual way by tapping on the end of the drawbar and it didn't budge. There are no signs of corrosion and the machine was oiled when it was stored. I don't want to hit the drawbar too hard for fear of brinnelling the bearings in the spindle. I heated the O.D. of the tool end of the spindle slightly with a heat tape that reaches about 200F, but it didn't help. I'm strictly an amateur at this. Is there a trick to getting out a stuck taper?

Steven L Jones
05-17-2001, 12:04 AM
squirt some wd40 around the taper ,then dont tap ,but give the draw bar end a good hit with a brass hammer, i am assumming that you have been able to unscrew the draw bar out of the taper some,if not able to back off the draw bar you can beat on the end all day long and not move the taper.

SGW
05-17-2001, 08:48 AM
You might be able to rig up some kind of puller to go on the front of the spindle, with a bolt going up into the collet's drawbar hole...assuming it's at least a 3/8" collet, or whatever the drawbar thread is.

But try Steve Jones' idea of some penetrating oil (I'm personally not all that sold on WD-40, I'd use something else, but the idea is sound) and a good clout with a brass hammer on the loosened drawbar. Some discretion on the hammering business is of course warranted, but it can certainly survive more than a "tapping."

Tommie
05-19-2001, 09:55 PM
If you can get a larger bar with a smoth end in the hole you can insert a small piece of brass rod in the hole first then a plane rod and whack it with out damaging the collet threads. I used that iewa on a Brown and Sharp arbor recently.

Richard Penney
05-20-2001, 12:24 AM
Been there! Rememember it is the sharpness of the whack that does the job! the arbor has less mass than the spindle and so will move while the spindle and bearing are unaffected.
I agree with the Kroil/WD theory and would suggest heat and cool cycles with it.
toff

Stuart Falkner
06-08-2001, 07:18 AM
Put a short piece of drill rod in the hole for the end mill and clamp it. Lossen the draw bar and start the mill on slow speed and run the side of the drill rod against a piece of scrap like you were trying to mill with it. A side load will usually make a tapered tool fall out if not held with a draw bar

Marvin R. Harbert, PE
07-04-2001, 10:54 AM
I've had better luck removing stuck metal things with a product called PB Blaster sold in most serious auto stores (Advance Auto etc.) It seems to penetrate better than wd40. I recently had a Reese trailer hitch with a stuck draw bar. I soaked the joint overnight with PB Blaster. I then rigged up a fixture to apply a "reverse pre-load" on it using my hydraulic jack. Then while it was under load I heated the outer case with my Map gas torch. When it got good and hot I gave it a wrap with a brass hammer and the draw bar came out like a shot--it even sounded like a 22! I knew we were getting close when It started to "grosn" Good Luck and be careful always stay out of the way of the path where the thing might fly!

Marvin R. Harbert, PE
07-04-2001, 10:56 AM
I've had better luck removing stuck metal things with a product called PB Blaster sold in most serious auto stores (Advance Auto etc.) It seems to penetrate better than wd40. I recently had a Reese trailer hitch with a stuck draw bar. I soaked the joint overnight with PB Blaster. I then rigged up a fixture to apply a "reverse pre-load" on it using my hydraulic jack. Then while it was under load I heated the outer case with my Map gas torch. When it got good and hot I gave it a wrap with a brass hammer and the draw bar came out like a shot--it even sounded like a 22! I knew we were getting close when It started to "grosn" Good Luck and be careful always stay out of the way of the path where the thing might fly!

Marvin R. Harbert, PE
07-04-2001, 10:56 AM
I've had better luck removing stuck metal things with a product called PB Blaster sold in most serious auto stores (Advance Auto etc.) It seems to penetrate better than wd40. I recently had a Reese trailer hitch with a stuck draw bar. I soaked the joint overnight with PB Blaster. I then rigged up a fixture to apply a "reverse pre-load" on it using my hydraulic jack. Then while it was under load I heated the outer case with my Map gas torch. When it got good and hot I gave it a wrap with a brass hammer and the draw bar came out like a shot--it even sounded like a 22! I knew we were getting close when It started to "grosn" Good Luck and be careful always stay out of the way of the path where the thing might fly!

Drillbilly
07-29-2001, 06:18 PM
I ran into this problem with my Carter Haks
#2 horazonal. I put a peice of bar stock. the size of the end mill shank. Grind a flat where the set screw goes. Then attach a slide
hammer to the bar. Give it a couple rapps. If
it don't come out remove the bar. Run the mill untill it reaches operational temp. Then
reinstall puller. And use a Co2 fire extingusher to blast the end mill holder.
Remember don't bang it to hard. You will
loosen the end play on the bearings.