Piero Franchi | 02/11/2016 11:05:02 |
124 forum posts 60 photos | Hi Guys
APART from using jaycob type wedges and a G clamp, how else do you remove a chuck from a Milling machine???
Mine is a 2 MT and I DONT want to wack the draw bar, it does damage your bearings.
on a Clarkson S chuck, it has a big threaded top hat, near the morse taper, you simply turn that and it brakes the chuck away.
simple, easy and no damage is done, only no other chuck that I know of or have use this simple device |
Journeyman | 02/11/2016 11:58:15 |
![]() 1257 forum posts 264 photos | Jacobs wedges and clamp will remove the chuck from it's arbor. They won't help remove the MT2 chuck assembly (arbor and chuck) from the mill spindle. Unless the mill has a captive draw bar you have little choice but to use a mallet to break it free. It may be possible to retro-fit some form of captive nut to the spindle depending on the type of mill, design of draw bar etc. John |
bricky | 02/11/2016 12:06:25 |
627 forum posts 72 photos | If you have enough meat in the top of the mill to tap it make a bridge bracket with it screwed to the top of the mill above the draw bar drill the bracket and tap and use a threaded bar or bolt to force the draw bar down. Frank
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Chris Gunn | 02/11/2016 12:06:56 |
459 forum posts 28 photos | Piero, a light tap with a copper mallet should release it without damage to the bearings. If it doesn't, then the draw bar has been tightened too much. Chris Gunn
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Piero Franchi | 02/11/2016 12:21:41 |
124 forum posts 60 photos | Thanks for the replys
First off, some milling chucks are a one piece construction, and some are two piece (arbor and chuck) yes jaycob wedges can split the two piece type, good point.
Pressing down on the top of the drawbar is not differant than giving it a light tap.
In my case, I was lucky to have found a NEW old stock knuckle head for my tom senior, and all my tooling (chucks) is new (being new to machining)
this means the 2MT fit is very very good/tight fit
I really would not like to have to whack the draw bar if possible
any other ideas ??? Edited By Piero Franchi on 02/11/2016 12:23:42 Edited By Piero Franchi on 02/11/2016 12:24:00 |
Tony Pratt 1 | 02/11/2016 12:46:50 |
2319 forum posts 13 photos | If you can support the spindle at the bottom end then apply pressure to the draw bar top the bearings will not be loaded. Tony PS never seen a 2 piece milling chuck? Edited By Tony Pratt 1 on 02/11/2016 12:48:41 |
Mike Poole | 02/11/2016 12:57:28 |
![]() 3676 forum posts 82 photos | As morse tapers are such a shallow angle they do not self release, the application of a drawbar very quickly makes them extremly tight. The only way to remove safely is to make an ejector that is part of the spindle. I have the same dilemma with my Myford lathe, the Rodney drive is by a morse adaptor and drawbar and this only needs the lightest of tightening or it needs a firm tap or two to remove. So far I do not have a solution but the bearings have survived up until now but I now rarely use the attachment. Removing any tooling from the spindle involves a tap or two and is the accepted method of removal. Myford did make collets with a screw ejector and tightening nut which works well but is not cheap. Mike
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John Haine | 02/11/2016 13:07:02 |
5563 forum posts 322 photos | I sometimes wonder how much worse the forces on a milling spindle bearing can be from tapping with a hammer on the drawbar from those resulting from a heavy cut. Obviously they are more axial than sideways, but all the same you would think that the bearing ought to be able to cope as long as you don't hit it too hard. And the other point is, don't over-tighten the drawbar, keep the socket and taper clean, perhaps apply a little light oil to the taper before fitting, and when you have finished take the chuck out rather than leave it in the taper. If really concerned make a drawbar with a "differential screw" arrangement for extraction. When I bought my Myford VMB I deliberately chose an R8 spindle to get better grip and easy extraction, rather than the MT3 option. |
Piero Franchi | 02/11/2016 13:18:35 |
124 forum posts 60 photos | I did ask this question before, on the Tom senior yahoo group. some guy made a comment that he made a good living out of people whacking drawbars and the like, ballbearings will be damaged, tapered or neddel rollers, less so. But Think hiting said drawbar is barbarik lol |
Bazyle | 02/11/2016 13:45:41 |
![]() 6956 forum posts 229 photos | Did you check that the quill doesn't have a slot for a wedge? Easily overlooked. If the wedges remove the chuck head it just makes it easier for supporting the spindle as mentioned above before applying the hammer so still worth attempting. IF you don't have wedges a large spanner or two can be used with some thought. |
Piero Franchi | 02/11/2016 13:59:15 |
124 forum posts 60 photos | I was thinking on the lines of a automotive ball joint splitter, only in principle |
Neil Wyatt | 02/11/2016 14:25:09 |
![]() 19226 forum posts 749 photos 86 articles | Make your own captive draw bar, this is mine for an X2:
Edited By Neil Wyatt on 02/11/2016 14:25:30 |
Howard Lewis | 02/11/2016 18:14:23 |
7227 forum posts 21 photos | Hopefully, the quill will have a slot, into which can be placed a tapered drift, specifically for removing a rbors withas tang. Rather than making a self releasing drawbar, I made a slight mod to my RF25, (which has a 3MT quill). Remove the left hand thread nut that holds the spindle pulley. Turn it down, to the across flats size of the nut, or just under, for a little more than the thickness of the plate that you choose, no more than half the thickness of the nut, to leave a register Take a piece of 6mm plate/flat bar, bore a hole in the centre to fit over the register in the nut, and then tap two holes, (M6?)equally spaced about the centreline, on a diameter, (say 13mm) larger than the corner/corner dimension of the nut. (Use fine threads - my version is 1/4 BSF) Take another piece of the same 6mm plate/flat bar, drill and tap on centreline for your choice of forcing screw. Drill two clearance holes to match the tappings in the first plate/ flat bar. Make up two clamp screws (Loctite knobs or nuts, onto studding?, or use long setscrews. Screw these through the second plate. Fitting a nut to each one on the underside, will make them captive. Place the plate with the register over the spindle. Refit nut, (register downwards) engage the register in the plate, and tighten nut. To remove a MT arbor; slacken the drawbar by a half turn or a turn. Place the plate with the forcing screw over the drawbar, and screw the two long setscrews into the captive plate. (Stop just before the setscrews contact the pulley) Tighten the central forcing screw onto the top of the drawbar, This should release the taper. If it doesn't, with the forcing screw really tight, give the top of the forcing screw a light tap with a mallet. This should release the taper, without subjecting bearings to too much force. Howard |
Vic | 02/11/2016 19:08:16 |
3453 forum posts 23 photos | I made a self extracting drawbar for my VMC but still have to "tap out" my drill chucks as they're on tanged arbors. They don't take much to knock out though. |
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