Help MT2 stuck

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Looking at your photo it looks like you have heated the morse taper judging by the blue tinge , Surly that would make the MT expand making it tighter , I think you need to heat up thr part it goes into ?
 
@Blister Well spotted. Your sort of right😀
We heated the nut which held the collet in, it was solid. In the end we used a nut breaker to get it off. We couldn’t get it to undo.
The heat cycle I’ve done on getting the MT2 out was on the spindle with the centre of the MT2 cooled.
It’s lying on my bench looking at me daring me to have another go at shifting it. So far it’s MT2 six : Deema zero🤬
 
Deema if a man with your wealth of experience and knowledge is stuck (no pun intended)them what hope is there for us mere mortals:LOL:
 
How on earth does my auto correct get Pilkington from Looking ??
I suspect that is mostly the robomoderator, some of the substitutions used do raise an eyebrow - "turnip" files is the usual one. In this case probably preceded by a typo. Perhaps L->F, that doesn't result in the usual spelling but it's a common enough variant it may be recognised in its own right.

I just tried putting it in here as an edit but it wasn't altered. OTOH does the robot look at edited posts?
 
Leave your jacking gear in place, cranked up to max, throughout the following.
Leave it immersed overnight in penetrating oil. Once removed and cleaned off, heat the shaft as fast as you safely can (to limit heat transfer to the MT inside). Spray a can of freezing fluid into the MT. It may just shock it off.
Not guaranteed to work!
 
Would welcome any ideas, hints or suggestions.
Well, we have an MT2 arbour stuck in a shaft and will not budge. I’m running out of ideas on how to get the two apart. It does not have a slot for a drift, so no chance of getting at it from the rear unfortunately. It’s a high speed shaft, part of the pin router we are renovating: we have a thread about it.

So far tried dunking it in penetrating oil, percussion encouragement, heating up the outer, and applying a lot of pressure to pull it out. It’s being stubborn and not shifting. This is the arrangement we came up with to pull it, it’s very difficult to get anything to pull. However, there are a couple of bolts pushing the two clams apart.


View attachment 143236

They say there's no such thing as a studif question. Well, mine is going to come close.
Are you 1000% sure it's simply two MT surfaces mated and that it's not threaded? I kno wit would be unusual etc....but sometimes strange modifications get made. Also, what's the arbor mounted in?
 
Hmmm. That's making me wonder.
It looks like a MT shank collet holder pushed into a MT2 socketed spindle.
There's no drawbar to keep it in.
The only way to pop it out originally looks like it might have been paired wedges - but nothing came with it.
There are no flats to unscrew anything and I don't recall anything that could serve as a spindle lock.
It was red rust on the table and rain has been down through the head.

But - it's a router, like milling machines they are subject to side load, so a simple push in morse taper wouldn't be ideal to keep the arbor secure. It might be like milling with a pillar drill, the chuck tends to vibrate loose and fall out.

I'm sure I recall that some kinds of old routers, and certainly old mills, used screw shank cutters.
I wonder if the arbor could possibly, somehow, be screwed even though there's nothing visible that suggests it.

If we sacrificed the arbor, we could just cross drill right through the threaded portion of it, put in a tommy bar and impact it.
An old 1/2" square drive socket big enough to fit over the threaded end of the arbor and angle grind two slots to fit over a tommy bar. Then grip the spindle and use an impact driver to get percussion on the socket to try and break it loose or unscrew it ...

Or even weld a short square drive extension into / onto the end of the arbor and do the same.

(Check the spindle direction of rotation first)
 
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On a more serious note it would certainly be useful to know for certain what you are actually dealing with, MT or threaded. I wonder if it would be worth extending your search for help to other machinery related forums. With a bit of luck you will find someone who is familiar with the machine and knows exactly what it is, and may even know some trick for removing it. You might even find someone who has the very same machine, always useful as a source of information.
 
I have the maintenance manual which SCM very kindly dug out for me. It certainty shows it as a plane MT2 shank held bu a nut, which we did release. I love the warning……clearly lost on the previous owner!

5581652F-0828-49C2-B5C0-09AB72FECEF7.jpeg
 
Do like Inspector's idea of using hydraulics, and has the advantage that you could use the same technique if it ever got stuck again. Only other thing I can think of it you are convinced is is rusted in would be a soak in a weak solution of phosphoric acid, or even a cycle of electrolysis to dissolve the rust. Never used either technique specifically for this but have been surprised in the past how both get in between parts that appear to be completely solid. Might be worth a try.
 
Worst case scenario I suppose would be to have it ground out and a new one manufactured, together with the nut. Surprising they didn't provide some means of getting it out especially since they were obviously aware of the risk of it getting stuck! Certainly something to think about as part of the rebuild.
 
Is it possible that the tapers are rusted together?
It may help to firstly hit the flange as though to tighten it to loosen the grip, then hit the flange on both sides to release it. I also think a heavy duty slide hammer attached to the flange is the answer.
Used to have one which had the head of a 14lb sledgehammer drilled through lengthwise to slide on the shaft. Nothing resisted it for long!
 
A couple more schematics which show the construction. We have released the shaft from the housing.

20F2A8E3-C101-4A78-8EF4-1B9EBE9391E5.jpeg
0CEC0CAA-2819-401D-89EA-E58D6F193B61.jpeg
 
Thinking of how to attach a slide hammer. Could you find a replacement for the collet retaining nut? I'm thinking a bar machined to imitate the collet and held in by its retaining nut, with the hammer attached to the other end. Thick plate with a hole just big enough to pass the arbour to act as a stop. If the hammer is good and heavy then you will have a nice straight shock. I have used a similar set up in the frame of my press, so the shaft is vertical and you just have to lift the weight up then let it go. MT2 can only put up so much of a fight surely :unsure:
 
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