Milling collet arbor jammed in milling machine

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Milling collet arbor jammed in milling machine

This topic has 83 replies, 22 voices, and was last updated 6 June 2010 at 16:26 by Chris Trice.

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16 September 2009 at 11:08 #43541
Julian
Participant
@julian
I have a Warco ZX15 mill drill, I’ve had it about 2 years and it’s fine.

However there has always been a problem with my Vortex collet chuck, it’s a Morse number 3 taper, and seems to be too good! It is very difficult to get it back out when I wish to switch to the drill chuck. In the past I’ve had to resort to putting a steel bar down through the spindle and whacking it with a lump hammer, not exactly how you want to treat a precision machine! The problem has diminished over the past 2 years – it’ was still difficult to get out, but not as bad as originally.

Then, last week, I made the mistake of oiling the taper before using the chuck. Now it refuses to come out. I have tried everything, even a sledge hammer – the steel bar mushroomed. I’ve tried huge levers to lever it out. It is stuck fast, and I have no idea what I can try. I tried running a blowlamp over the spindle, to no avail.

Any ideas? And why on earth does it get stuck like this? the drill chuck is fine in there, and comes out with a light tap..

If you can offer any suggestions I shall be very grateful.

Julian
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16 September 2009 at 11:08 #11602
Julian
Participant
@julian
16 September 2009 at 21:02 #43561
Peter Tucker
Participant
@petertucker86088
Julian,

I resently over tightened the 3MT collet chuck in my mill. To free it I made a pair of forked wedges each aproximatly 3″x3″ one edge nearly feathered the other 1/4″ thick , a 1″ wide slot milled from the sharp edge 2/3rds of the way to the back. The wedges are placed between the spindle nose and chuck, hold the head of the club hamer against the back of one wedge and tap the other with a light hammer. The MT should come out easily, mine did.

Peter.
17 September 2009 at 12:15 #43568
Circlip
Participant
@circlip
Peters given you the answer Julian, all you’ll succeed in doing with the fifth law of clout is damage the spindle bearings. Do you use a drawbar?? If so, tighten with a smaller spanner, suprising how many seem to think they have to swing on the end of a two foot (600MM) ring key to get a morse to hang on.

When you get it undone, you might think about releaving the middle three fifths of the taper (Two fifths if yer not sure) so that you’re gripping on two bands at the ends of the chuck shaft.

Regards Ian.

Edited By Circlip on 17/09/2009 12:16:05
17 September 2009 at 15:21 #43575
mgj
Participant
@mgj
True – and if you can’t get it out directly with the wedges, tap them in firmly to put tension on, and then tap the end of the chuck or whatever between two hammers (from two sides) to induce a shock. Just like freeing any jammed taper – car swivel bearings spring to mind.

Then were I you, I’d be looking in my parts list to find out what the bearing numbers are – because they are screwed. No question – change them.Others may disagree, but I wouldn’t even think about keeping them if they have been beasted like that. I might also look at the downfeed rack and worm, and just make sure that doesn’t bear any witness marks.

I doubt the oil hurt – the taper was just doing what it was designed to do. To support Circlip, but in principle its the angle in the taper that does the holding and provides the self locking effect. All the drawbar does is to stop it pulling FORWARDS – it doesn’t lock the taper in place, so it doesn’t need more than nipping up.

This is the advantage of the R8 and Int tapers. They are too steep to self lock. The taper locates, and drive is provided by a dowell or peg.
17 September 2009 at 16:15 #43577
chris stephens
Participant
@chrisstephens63393
Hi Julian,

Just an off the wall idea that might work, would be to put your largest milling cutter in the holder and, having removed the draw bar, mill the edge of a lump of steel. The principle involved is that morse tapers do not like side loads and tend to vibrate out, this is what the draw bar is intended to stop. I might suggest you put a piece of wood under the cutter to catch it as it falls out, theres confidence for you.

I agree with others when they say buy a smaller spanner!

chris stephens
17 September 2009 at 17:36 #43578
Funnyturn
Participant
@funnyturn
Right or wrong, should I (lightly) oil/grease the taper before fitting?

As a newbie I thought this a ‘good idea’…

Brian
18 September 2009 at 04:53 #43596
mgj
Participant
@mgj
Personally I think it an excellent idea, along with wiping all tapers (chucks, reamers etc) with an oily rag after use to prevent rust.

Oiled or dry I’ve never had one jam up – but then I suspect I have never been quite so anxious about locking it in place either!

To go along with Chris above – that could well work. I think I might tip some Plus Gas down from the top of the spindle and leave it overnight, before trying.
18 September 2009 at 05:41 #43597
Peter Tucker
Participant
@petertucker86088
I would only try Chris’es idea as a very last resort, the thought of a chuck with large cutter spining out of the spindle is not a prety one.

It dosn’t take a large spanner to over tighten the MT, I inadvertently did so with a 6″ open spanner.

Peter.

Edited By Peter Tucker on 18/09/2009 05:42:54
18 September 2009 at 09:15 #43599
LADmachining
Participant
@ladmachining
If you use the ‘milling the steel’ method to free the taper, install the drawbar just enough so that it is a millimeter or so short of seating fully on the top of the spindle. When the taper does release, the free space will allow the taper to disengage, but the drawbar will catch the arbour and prevent it dropping out completely.
18 September 2009 at 09:31 #43600
David Clark 13
Participant
@davidclark13
Hi There

I don’t think this is advisable.

If you put the drawbar in and leave it loose, the cutter will probably tighten up on the drawbar while it is going round.

Probably be impossible to remove.

Have you tried gently tapping the side of the tool holder?

Alternativly make a threaded drawbar that screws into the top of the arbor and whack that with a big copper mallet.

You should not need to hit it that hard to remove it.

One other method that has worked in the past.

Hold the cutter in the vice and lower the table or raise the head depending on the mill.

regards David
18 September 2009 at 12:30 #43610
Ian S C
Participant
@iansc
Stick with the wedges,a similar system used on car suspension might be worth looking at if you can borrow from a mate,its too expensive to buy for hopefully one off job.
18 September 2009 at 12:57 #43614
mgj
Participant
@mgj
Large cutters spinning out of spindles?

Team we’ve had drill chicks come loose – all that happens is the taper releases and the chuck stops turning. Its not as if we are going to select maximum revs are we.

Low speed, start with a fairly light contact,short distance to top of block of wood. Its just going to drop onto the drawbar, or top of block of wood and stop. If there is only a small gap between bottom of cutter and wood/table it cant go anywhere because the lenght of the taper is going to stop it . It won’t have eanough spce to go walkabout.

If the chuck does tighten on a loose drawbar – I’m afraid I don’t see the physics of that possibility because there is nothing to hold the drawbar against rotation – to the point of no release. Lift head of machine, cut drawbar, turn spigot on lathe to fit collet or whatever, centre drill and drill out. Chuck recovered. Make new drawbar for working milling machine.

If in doubt, stand well clear – like near the mains switch on the wall.

We are getting a bit over H&S?
18 September 2009 at 15:25 #43618
Circlip
Participant
@circlip
Bits of flying HSS cut unbelievably deeply Meyrick. and even with the disposable income of SOME, PROPPER cutters are quite expensive.

NEVER consider “over H&S”, your employer doesn’t HAVE to pay your wages for self inflicted injuries.

Had I done something like that as a slave, the injuries would have been CLASSED as self inflicted by the toolroom forman holding the bit of 4 x 2 he’d just massaged my memory with.

Regards Ian.
18 September 2009 at 16:08 #43619
chris stephens
Participant
@chrisstephens63393
Hi All,

One sometimes forgets that some others need to be lead by the hand through lifes difficulties. The method I suggested is perfectly safe if one has ones wits about them and obviously does not fit a 3″ cutter and turn the revs up to 3,000. The likely largest cutter that will fit is 3/4″ and at 3-500ish RPM and the piece of wood no more than 1/2-1″ below, (you need a largish cut to jar the holder loose) there is very little to no risk of personal harm, to you or the machine. If H&S don’t like it, don’t tell them! Without some excitement at home, we would all have to go to Alton Towers every week to prove we are still alive.

The reason I know the method works is because many years ago, pre-milling machine days, I used a drill press and cross slide vice for small (very) milling jobs. The chuck would often fall out, even when loctited in!

chris stephens
18 September 2009 at 17:53 #43620
mgj
Participant
@mgj
Bits – of flying HSS – So whats happening on an ordinary milling cutter? Or a 2″ tipped facemillat 500rpm? Or a gear cutter? They are all going round – on an interrupted cut, and I don’t see that we’d all be assessing the risk (Oh god!!) as high .And on the very rare occasions when one of those breaks, one doesn’t notice bits flying over far.

Maybe I haven’t done enough milling, but such things do not seem dangerous to me. Start putting fingers in there to see if its hot, or peering into rotating machinery without safety glasses, go mixing cloths and clothing with rotating machinery, or trying to hold jobs down by hand, etc different story.

So lets be realistic.

If someone goes at it at warp speed on max power feed and generally behaves like a complete fxxxwit……….Clearly they are getting down on bended knee and begging for trouble, in which case they should hardly be surprised if it is visited upon them in full measure.

At the end of the day the individual is responsible for his own actions, and will presumably consider the problem slightly before doing something so spectacularly stupid. (Such as playing conkers without a face mask!!!!)

Last 2 points

1. We aint at work, so we can do as we please, subject to the above.

2 H&S doesn’t stop people from doing things. All it actually says is that if one is going to do something, you do it in a considered way, such that the risk is minimised.

So if one is going to use Chris system which might well work, take precautions, don’t go at in a stupid way, ensure bits are retained and keep clear.

——————————-

I can light a gallon of petrol safely, and I can equaly half blow my head off. The difference is the degree of brain engagement?

Edited By meyrick griffith-jones on 18/09/2009 17:54:30
19 September 2009 at 11:21 #43637
Circlip
Participant
@circlip
Seems there’s only me an thee on this one David?

Just proves how wrong we can be.

Glad I’m a CAREFUL f***wit. If you READ what I rote re ones employer NOT having to pay ones wage for a self inflicted injury, I said NOTHING about it occuring at work.

When a method is posted on open forum that can only be described as a bit iffy, how have you the audacity to assume that all the readers have the same intellectual prowess that you obviously have meyrick?? And sorry Chris, to admit using a drill chuck for a “Small (Very)” milling job beggars belief.
19 September 2009 at 14:36 #43643
chris stephens
Participant
@chrisstephens63393
Hi Circlip,

Come come Sir, just what is the risk involved in using the described method and if you think it beggars belief, I wonder how you find the courage to cross the road without a “Lolliepop Lady” .

The worst, the very worst that could happen is that the chuck falls out and no longer turns. If the job gets damaged then that is just tough. Jobs get ruined, even with the most “safest” methods. Who has not had something come loose in the mill vice?

The beauty of a democracy is that you can do things your own way, if you are too timid to do something, then don’t do it! If one doesn’t push the boundaries, though, one would still be living in a village in Africa. The more adventurous of us wonder what is on the other side of the hill and go and look, thus spreading the human race thoughout the world. I am sure that there were some people in that village that said “you mustn’t go, you will fall of the edge” or some such. You note that it is the human RACE, I wonder if the creators of the English language thought that life should be a contest?

I am not advocating the wholesale use of dangerous techniques, for the masses., but needs must sometimes. I am not saying things like safety glasses are a waste of time or always wear a loose Tie when turning, that really would beggar belief.

I am sure that there are things you do, quite safely, that some Ninny thinks is “iffy”. One of the signs of intelligence is to be able to go beyond the teachings of ones tutors, that is how progress is made!

Safety is something I take seriously, despite what some may think. I am aware of the potential “risks” in my engineerium, but a risk known is a risk avoided. Every thing we do has some risk involved. Do you know some people actually risk their lives and that of others by driving cars!! A far more risky activity than having a drill chuck drop a bit.

So in inconclusion, I think you are over reacting to different techniques that you are unwilling to try, that is your right, but lets keep it real, shall we.

chris stephens

PS does anybody know if the collet holder at the start of this thread has come out yet?
19 September 2009 at 15:02 #43644
Circlip
Participant
@circlip
Just a bit of basic nomenclature Chris, DRILL chucks are for DRILLS, MILLING chucks are for MILLING cutters. Now consider the direction of cutting forces applied normally to the two types of machining. I’m not going to insult your intelligence by filling in the blanks. Yes, I have one or two cuts that have happened by taking calculated risks at times but I’m not stupid enough to advocate an operation where someone else could suffer the same type of injury by “Publishing” it.

No I dont need a LollYpop lady to escort me across the road (Yet) but neither do I advocate playing marbles on a Motorway.

Perhaps some should calm down from the human RACE and glance at the scenery now and again, don’t look for too long though, you might run into the back of me.

Regards Ian.

Edited By Circlip on 19/09/2009 15:22:31

Edited By Circlip on 19/09/2009 15:23:08
19 September 2009 at 15:09 #43645
mgj
Participant
@mgj
With respect – I credit the remainder on this forum with a degree of common. It would be audacious to assume that they did not have it.

Else every post would be more caveat than useful information.

Anyway, it’s too nice a day to have a squabble – over something that is outside our control. Hopefully this chuck has dropped out with just the wedges, and more extreme meaures are not necessary.
19 September 2009 at 20:03 #43649
chris stephens
Participant
@chrisstephens63393
Hi Circlip,

If you read my post carefully, I was not advocating people should use a drill as a mill. I was saying that it was a method of removing a chuck that was stuck. I explained how I knew it would work from personnal experience. I said I had used a drill stand and cross slide vice to do a small job only. Would I do it again, yes of course I would if there was no other method. Do I consider it best practice, no I don’t . If you have the right tool for the job, use it. I at that moment did not have access to one so I improvised, as any intelligent person would. Was it dangerous, no it wasn’t, there was nowhere for any rotating parts to leave the scene. At what point did I say you or any other person should follow my lead, other than using the method in a way that proves it is not “best practice”?

I ask you just what injury do you expect to get?

Best practice does not mean don’t do it , it means there is a better way.

At my prep school my old Maths Master used to advocate all Maths problems should be done as quickly as possible without pausing for thought. His reasonimg being the analogy of a saunter down a road, you don’t concentrate on the walk you GLANCE in gardens or house or whatever and bump into lamp posts or people, (or circlips). If you race down the road you concentrate on the job in hand and weave in and out of obstacles, thereby missing them.

Meyrick, yes it was a lovely afternoon, I was out in the garden watching a Hurrican do a flypast. Sheer bliss! Bit disappointed there was meant to be a Spitfire as well., but then I saw them both last weekend at Bentley Priory, so I have had my fix of V12 “music” for awhile.

chris stephens

PS Just to point out your error Circlip, Lollipop is not spelt with a Y, at least in my dictionary., but please this is an engineering site not “Countdown” , perhaps we could ask Mr web master,”Can we please have a “spell check” option on this forum?” ,for we poor illiterate dyslexics.
19 September 2009 at 22:48 #43653
mgj
Participant
@mgj
Ah well – when I did my young officers course, a very few (the Berlin Squadron and the gunner OPRA) were still on Centurion, though us Chieftain regiments still had Cent recovery vehicles.

So we got our V12 fix daily – though it wasn’t supercharged, and it wasn’t actually a Merlin – it was a Meteor and although it had Rolls Royce on the rocker boxes they were actually built by Rover.

Later I ran the Trials Section at Chertsey, and we had a tug with a Gryphon in it for pulling the early Challengers. (After the war many Gryphons ended up in MTBs which is where this one came ftrm. 1100 horse with little armour and no turret is still quite fun – esecially with a genuine crash box – double declutch up and down. And about 5-6 gallons per mile x country. Now thats what you call ecologically friendly driving. (The Cents were a bit more economical at about 3-5 GPM)

Still the sound of a real Merlin or Gryphon is just fabulous. We were later stationed at Saffron Walden, (Debden) just down the road from Duxford, and a lot of the piston engined fighters used hold over us quite regularly. Lovely to watch – brings a lump to your throat.
19 September 2009 at 23:27 #43654
chris stephens
Participant
@chrisstephens63393
Hi Meyrick,

How nice to hear the voice of reason, well words at least.

My evening shall now be spent watching our Badger in the garden, eating his fill of peanuts and dog food. Simple pleasures are the best, what?

chris stephens
20 September 2009 at 16:05 #43667
John Littler 1
Participant
@johnlittler1
Hi I have been watching the posts on the ME site re a stuck chuck in a ZX 15 mill. I have a Chester Champion, which I think is identical to the Warco ZX 15. Now I may, being a beginner, be missing something obvious, but my mill has a slot in the quill, visible at full extension, in which, having removed the drawbar, I tap a No 3 taper wedge; a smart blow on the big end of this with a 1lb hammer removes any tight tooling, with no risk to bearings etc, always bearing in mind that the falling chuck can damage the table, and if the blow is too gentle, the wedge can bounce back out, and hit something, or someone, fragile.
20 September 2009 at 16:35 #43668
chris stephens
Participant
@chrisstephens63393
Hi John,

I bow to your greater knowledge of such things.

Your method is “best practice” and should used in preference to all others when the situation arises.

If I was to be sarcastic, I might say that there are those amongst us who might say “It beggars belief to think that hitting the spindle, even via a wedge, with a hammer was to be publicly recommended” but what the heck, go for it!

What’s this about beginner, I have seen your work. “Beginner” is a state of mind, if you can produce the end product to the right standard, it matters not how long you have been doing it. In metal munching, the end product is the important bit, but hopefully you enjoy the journey too.

chris
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