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Elninio
08-07-2006, 09:28 PM
How do I remove the drill chuck from drill press off the MT? Whats the safest and easiest way to do this? The reason Im trying to do this is because every single drill bit that i put in the chuck isnt central to the turning axis. Suggestions plz?

Mcgyver
08-07-2006, 10:19 PM
it could well be a cheapo or damaged arbor - they're so try a new one or better yet you indicate the old jacobs taper with the MT held in the spindle - once you get it off.

like releasing any self holding taper, you've got to direct a bit of force opposite the way it came on.

these are the official way

http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=1785469&PMT4NO=10415313

some chucks are bored through so you can tap the arbor through the chuck with a punch (ie piece of AL or steel) and it should pop off with a good hit

less than perfect methods that I'd never do but have heard of :D ; hold the arbor in the vice and judiciously whacked the chuck body with a soft face hammer. with the same set up, another way is a piece of AL, say 3/4" dia used as a punch. place it on the body next and aligned with the arbor and tap around it. not so hard that you damage the body of course

Wareagle
08-07-2006, 10:33 PM
My dad had a drill press (not an expensive one) that we changed the chuck on several years back. It took us an hour of trying to knock the old chuck off with a wedge before we looked up into the mouth of the chuck to find that there was a screw and washer holding it on the taper . Once the screw was gone, the next whack took it off.

It might be worth the second it takes to look into the chuck to avoid our misery!

Elninio
08-08-2006, 12:28 AM
a couple times i was doing some sketchy drill and the vibrations caused the chuck to fall off so im sure that there is no screw washer holding it back, but in the case that i do get the chuck off, how would i make sure it goes on properly and has a strong hold.

ASparky
08-08-2006, 12:44 AM
Usual problem is either a ding or dirt so eye ball and clean. I am asuming it has an adapter from something like JT6 to MT3. If so put the adapter back in without the chuck and rotate and indicate the JT6 taper near the top and near the bottom, this will help tell you where the problem is.

BadDog
08-08-2006, 03:16 AM
The wedges are usually best where they will work. Some arbors have no shoulder and the wedges don't work. I'm told you can drill the arbor and place a pin through to give the wedges something to push against, but I've not tried it. On some you can also place hardened pins on each side between chuck back and arbor taper. Just pinch in a vice to put solid pressure, and tap with a lead/brass hammer, works most every time and I often prefer this to wedges. Here (http://www.jacobschuck.com/pdf/s1.pdf) is a PDF from Jacobs describing wedge, pin, and hole drilling methods. But note, the hole drilling only works for some chucks.

There are other methods as well. I’ve heard of using split collars to give the wedges something to push on. I’ve personally cut and bored out an arbor that would NOT give up otherwise. Others report having luck with stuffing a rag in a pipe to catch the arbor, placing the chuck on the end of the pipe with the arbor inside, and then SLAMMING it down on concrete to eject the arbor by inertia combined with shock. Then again, you may need to use heat if something like Locktite has been used to hold the arbor in the chuck. But be careful since heat can damage the chuck in several ways including cooking the grease, damage to seals (most don’t have), and even drawing back hardened parts that should not be drawn back...

lynnl
08-08-2006, 11:22 AM
How do I remove the drill chuck from drill press off the MT? Whats the safest and easiest way to do this? The reason Im trying to do this is because every single drill bit that i put in the chuck isnt central to the turning axis. Suggestions plz?

Don't mean to offend, but are you checking to insure that you do indeed have the drill centered in the chuck?

I find it very easy to mount the drill skewed off-center in a drill press chuck, particularly smallish drills. Don't have that problem with a handheld drill, which can be held such that the chuck/drill is easily seen while mounting. But with that chuck opening below the line of sight on a drill press it can be a problem.

pcarpenter
08-08-2006, 12:11 PM
I just had a chance to try a different chuck on a Jacobs/Morse arbor and this is the second one with substantial runout. Time to check the arbor.

One tip I found interesting on the Jacobs web site is that they suggest that you can bore through the center of your jacobs chuck to allow a punch to be used to push the Jacobs taper end out of the chuck. They suggest that the center of the chuck is not hardened. I have several chucks that already came with a through hole in the center, but just bought a used Jacobs keyless industrial model, used, that did not have this.

Of course, the wedges are probably the right way in the case of no through hole, but at around $7 per set, it would probably make sense to buy a set for one of the larger Jacobs tapers so they could also be used with the smaller ones.

Paul

BillH
08-08-2006, 12:33 PM
I was trying to remove the chuck off the cheap 20$ on sale HF drill press when I remembered that I had locktited the damn thing on when I first got it! Oh well. If I really wanted it off all I'd have to do is heat it up.

JCHannum
08-08-2006, 02:32 PM
I just had a chance to try a different chuck on a Jacobs/Morse arbor and this is the second one with substantial runout. Time to check the arbor.

One tip I found interesting on the Jacobs web site is that they suggest that you can bore through the center of your jacobs chuck to allow a punch to be used to push the Jacobs taper end out of the chuck. They suggest that the center of the chuck is not hardened. I have several chucks that already came with a through hole in the center, but just bought a used Jacobs keyless industrial model, used, that did not have this.

Of course, the wedges are probably the right way in the case of no through hole, but at around $7 per set, it would probably make sense to buy a set for one of the larger Jacobs tapers so they could also be used with the smaller ones.

Paul

The keyless models are similar to the Albrecht chucks, and drilling through them will destroy them. Wedges or machining the JT out are about the only methods available for them.

The wedges are size specific as they have to fit the hole of the JT mount closely and bear against the shoulder of the chuck and that of the adapter.

There is no best or surest method, but drilling and tapping the chuck for a jackscrew and using this to force the chuck off will usually be successful.

Use as large a thread as possible, preferrably fine. I prefer a SHCS, tighten it as tight as possible. If the chuck does not come off, a large hammer applied to the screw head often provides the final persuasion needed.

Failing that, drilling and boring are about all that is left.

BadDog
08-08-2006, 04:12 PM
Yes, the wedges are JT taper specific, sorta. There are some tapers for which there are NO wedges made, but you can get them by using other tapers. For instance, there is no JT33 wedge set, but you can get them with a JT6 taper. I also seem to recall that there was some combination of wedges for other JTs that would fit a JT4, but can't find the site that listed which to use for what...

And that back wall is VERY thin, so a fine thread would be advisable, though it may still strip on a stubborn arbor.

BadDog
08-08-2006, 04:16 PM
Oh, and I forgot about the hydraulic multiplication method. Drill a hole in the chuck, turn a snug fitting "piston", fill with hydraulic oil, smack piston with big hammer. Particularly good (though it didn't work for me) with the JT4 since it has so much more surface area for the driven "piston", and so, has much more "multiplication" of force.

YankeeMetallic
08-08-2006, 11:33 PM
The taper wedges of different sizes purchased through ENCO are the easiest. The are inexpensive and they are quite handy on removing other things like bearings on a shaft etc. I have numerous sets of each in case you are trying to cover a large gap.
If you are using a KEY chuck and have to remove it on a regular basis, you can bore a thru-hole through the chuck about 1/16th inch smaller than the chuck capacity. Then you can use a puller (pitman or bearing type) so you can screw the main screw through the hole in the chuck and use the jaws to clamp on the side of the chuck. I use both setups often to remove tapered shafts.

Elninio
08-09-2006, 04:12 AM
Don't mean to offend, but are you checking to insure that you do indeed have the drill centered in the chuck?

I find it very easy to mount the drill skewed off-center in a drill press chuck, particularly smallish drills. Don't have that problem with a handheld drill, which can be held such that the chuck/drill is easily seen while mounting. But with that chuck opening below the line of sight on a drill press it can be a problem.

yes im sure its centered, what i do is a turn the drill and tighten from each side of the chuck, also before doing it with a drill bit i had a mill bit in there and the flat channel is at the exact height as one of the jaws in the chuck and i made sure that the jaw does not clamp onto that channel

Elninio
08-09-2006, 04:13 AM
Usual problem is either a ding or dirt so eye ball and clean. I am asuming it has an adapter from something like JT6 to MT3. If so put the adapter back in without the chuck and rotate and indicate the JT6 taper near the top and near the bottom, this will help tell you where the problem is.

It doesnt have an adaptor, the chuck goes straight onto what looks like a MT2, this is the delta drillpress that u can get at any canadian tire (smallest model)

Elninio
08-09-2006, 04:25 AM
Sorry, heres a quick update:

i started using this drillpress alot with a new cross sliding vise table i had recently purchased, anyways i had this problem before but i really didnt pay too much attention to it because i wasnt doing any precision work, but now that i was milling these vibrations became... dangerous!. Anyway i couldnt figure out what to do about it so i decided it to leave it alone (i thought i was something un-fixable, like a bent spindle or chuck or something). Anyway i pushed the limits w/ this setup and i was pretty impress when i managed to cut a channel in a piece of round cold rolled steal w/ a half inch mill when all of a sudden the chuck w/ the mill just fell off! The chuck landed on the concrete with the mill pointing up and bounced on the carpet, i came really close to wasting that mill bit, anyways after cleaning the tapers with disc-brake cleaner i put the chuck back on the spindle, and then hammered it lightly and fast as it was spinning at a slow speed, and then hit it really hard on the center w/o it spinning. After that i seemed to turn true, i approched a metal ruler to the smooth part of the chuck in between the knurls and the non-fluted part of the mill and it did not seem to repel the ruler (sort of like when you use your grinder w/ a brand new wheel), so it seems to be OK now. I really didnt expect much from such a cheap investment (20$) but it is pretty cool that i can mill a bit of tough steel, also it cuts aluminum like butter! What really sucks right now is the huge ammount of play in the screws of that cross-sliding vise, its not even adjustable =(

BadDog
08-09-2006, 01:39 PM
There is no drill chuck that I've ever heard of that mounts to an MT anything. If you have a spindle that does not take an MT arbor, then the spindle will (always?) have a JT (or screw on? is that a JT?) on the end so that common chucks will fit.

As for milling with a drill press, particularly a cheap one, that's a whole different discussion. But if you keep side loading that spindle, you'll wreck the spindle and/or the bearings as well as never be able to keep a taper mounted chuck on the spindle (among other problems).