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Anyone with a Chester 626 mill can help me with a little problem?

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Gavlar01/11/2020 10:50:19
79 forum posts
4 photos

I have recently aquired a (barely) used Chester 626 Mill. It was a probate sale, so the seller can't help me.

It came with no tools and the manual doesn't help.

There is a reducer in the spindle to take 2MT tooling. I want to know how to remove this reducer. The reducer itself looks to be 3MT, it is not held in with a draw bar, the draw bar was screwed into the 2MT chuck.

There are two flats on the reducer that suggest it unscrews but I'm not sure. I'm guesing there should be some sort of keyed spanner to lock the rotation of the spindle but again, I'm not sure.

Before I go to the lengths of sourcing a correctly sized keyed spanner, can anyone advise me on the correct way to remove the reducer, please?

Thank you



John Rudd01/11/2020 11:02:32
1436 forum posts
9 photos

Gavlar, there should be a slot in the quill to accept a 'drill drift' for removing tapered items.....

Else a long rod of appropriate diameter inserted from the top, smartly struck with a deadblow hammer ought to remove it....but the drill drift is the preferred option.

Ian Parkin01/11/2020 11:16:47
972 forum posts
231 photos

I don’t know about your mill but many don’t have the slot to remove taper tooling if its to be held in with a drawbar.

the adapter wont have a tang on it just an hole in the top to pass the drawbar through

you may be able to twist the adapter out if you cobble up a tool to hold the spindle and use a long spanner on the adapter flats

or you may get lucky with a rod down the drawbar hole catching on the top of the adapter to loosen it

Martin Connelly01/11/2020 11:17:04
1848 forum posts
197 photos

First off the Grizzly manuals for their version of the 6x26 milling machine is here. The Grizzly versions are often far better than the basic ones supplied by some UK suppliers Grizzly G0801 manual

Secondly the spindle probably has an open ended morse taper sleeve stuck in it. It may be hard to get out without destroying it but they are relatively cheap so do not worry too much about abusing it as long as you do not harm the machine's morse taper in the process Arceurotrade example

I doubt a rod from above will get to the top lip of the sleeve and an extractor slot approach may be better (if there is such a slot on your version of this machine). I think there have been past threads on this subject so it may be worth searching past threads.

Martin C

Past thread on this subject Thread 35680

Edited By Martin Connelly on 01/11/2020 11:19:20

Vic01/11/2020 11:20:27
2894 forum posts
8 photos
Posted by John Rudd on 01/11/2020 11:02:32:

Gavlar, there should be a slot in the quill to accept a 'drill drift' for removing tapered items.....

Else a long rod of appropriate diameter inserted from the top, smartly struck with a deadblow hammer ought to remove it....but the drill drift is the preferred option.

This type of machine doesn’t have a slot, at least my Warco VMC, which is essentially the same mill doesn’t have one. On R8 versions of the machine tooling will fall out once the draw bar is undone. MT3 machines require a sharp tap on the drawbar with a copper hammer as you say.

Assuming it’s a type of MT3 to MT2 sleeve it should just knock out but who knows what the previous owner may have done?

John Hinkley01/11/2020 11:21:02
1170 forum posts
390 photos

The 626 is a cousin of the VMC, one of which I have. There is no slot in the quill, unfortunately, and it sounds like the reducer is just plain stuck in the quill. I suggest that you put a piece of tubing over the reducer such that it bears on the quill at the top and the table bottom - with suitable protection for the table. Then proceed as John Rudd suggests. With a bit of rod down the spout, give it a whack and it should pop out. An overnight soak with penetrating oil might help, too.


Slower at typing than Vic!

Edited By John Hinkley on 01/11/2020 11:22:10

Dusty01/11/2020 11:28:40
485 forum posts
8 photos

Do not be tempted to try and remove the sleeve without supporting the bottom of the quill, I use a couple of pieces of wood either side if I have an obstinate sleeve or chuck to remove, otherwise you risk damaging your bearings.

My 626 does not have a drift slot either.

Edited By Dusty on 01/11/2020 11:29:46

Ian Parkin01/11/2020 11:53:13
972 forum posts
231 photos

094989fd-f3db-40c4-9d59-ddd4e07fe06c.jpegThis what you will have up your spindle


Edited By Ian Parkin on 01/11/2020 11:53:37

Ian Parkin01/11/2020 11:56:25
972 forum posts
231 photos

This what you need

good old arc

Gavlar01/11/2020 12:06:06
79 forum posts
4 photos

Thanks all, especially Martin, for the link to the Grizzly manual. It is much better than the one it came with.

There is no slot in the quill.

It does appear to be simply a 3MT to 2MT reducer, the internal diameter of which is the same as the internal diameter of the quill so I can't knock it out.

I think then I have two options;

The one which will take a little more time but be less likely to do damage will be to knock up something to lock the spindle, then try and twist it out and if that doesn't work, drill and bolt through the adaptor, then try and knock it out from above, using supports as Dusty has suggested.

Thank you all.

HOWARDT01/11/2020 12:40:14
776 forum posts
28 photos

If the diameter at the small end of the taper is less than the bore through the spindle you will have a shoulder to pull against. Make a thick washer with a clearance hole though for a suitable stud. Also make a piece or use tube to go over the reducer onto the spindle nose which is longer than the reducer. Now drop a stud with nut through the spindle and collar. Put a collar on the stud across the spacer then a nut. Tighten nut to crack the locking taper.

john halfpenny01/11/2020 13:03:06
185 forum posts
25 photos

Arc sell this adapter, and say the flats are used to twist it out with a spanner. The drawbar passes straight through to engage whatever is held in the open end.

not done it yet01/11/2020 13:04:29
6270 forum posts
20 photos

A spanner to twist the sleeve is all you should need, to remove it.  This is assuming (hoping) the sleeve was not inserted, while cold, into a warmed machine🙂 ).

Check out what Arc say about it.


I learned something new just a couple of days ago.🙂

Edited By not done it yet on 01/11/2020 13:09:29

Clive Foster01/11/2020 14:02:47
2815 forum posts
101 photos

The trick to releasing stubborn, but otherwise unconstrained, tapers is to induce some vibration into the system.

I learned that many years ago when trying to remove the flywheel from an Acto rotary mower. Proper pullers failed miserably so I eventually forked out for the official tool. Turned out to be a simple bit of round bar with a thread to screw into the end of the crank. An expensive bit of bar but I was assured that it would do the job. Muttering dark threats about what would happen if it didn't I screwed it in, lifted against the flywheel with one hand and rapped the end sharply with a club hammer as advised. There was an audible Rinnngg and the flywheel popped off just like that.

In the intervening years I've seen a few drill chucks separate from their taper when the drill vibrates.

Getting back to your problem I'd make a suitably substantial device to clamp round the quill when it is extended an inch or so and bolt it to the table so all is solid. I'd be thinking in terms of two arms maybe an inch or more square with suitable half circles at the end to clamp the spindle. Needs to be solid and clamped to the machine table so forces don't go through the quill bearings.

Make a solid clamp on spanner to go on the end of the jammed in adapter and give it a sharp rap or two with a club hammer. The technique is more of a fast puch through rather than hefty knock. Speed and monetum does the work. It will move.

Creating properly effective tooling for this sort of thing always seems a metric boatload of work. But generally 5 minutes trying the simple way and, perhaps one bodge, followed by making the right stuff is faster than spending a day trying "a number of things" before giving up and setting down to toolmaking. Trying" a number of things" seems to have a high risk of damaging parts too. Often expensive ones. One such mishap cured me of the habit!

Once its out take a good look at the small end.

Most of these adapters have a short parallel section at the end of the taper. I've seen one machine & sleeve combination where the parallel portion was a little too large to enter cleanly into the quill beyond the taper section. Fortunately that one was sufficiently oversize that it was obviously not going to go. The parallel portion always has a chamfer or similar on the end to break the sharp edge. I can easily imagine a situation where the disparity in size is small enough that the sleeve is only a few thou short of proper seating before the marginally oversize parallel part grinds its way into the quill bore. Should that happen its going to be seriously, seriously tight.

Best to verify that isn't an issue.

All from the "Don't do as I do, Do as I say book.". If it were mine I'd just weld a filler in the sleeve, set up a quill support spacer as advised above, bonk it out and drop in the scrap bin. My time and effort to do a proper, damage free, extraction is worth vastly more than a new sleeve.


Edited By Clive Foster on 01/11/2020 14:03:23

Edited By Clive Foster on 01/11/2020 14:04:07

Edited By Clive Foster on 01/11/2020 14:04:41

Vic01/11/2020 15:16:09
2894 forum posts
8 photos

Once the sleeve is out put it a bottom drawer somewhere and buy some MT3 tooling, preferably with an M12 thread. smiley

Gavlar01/11/2020 15:28:15
79 forum posts
4 photos

The only piece of MT2 tooling I have is the chuck that was in the jammed reducer! All my other tooling is MT3. I specifically wanted an MT3 mill as my previous mill was MT3 as well as my lathe tailstock, so even if the reducer comes out in perfect condition, it's going in the scrap bin!

not done it yet01/11/2020 18:18:46
6270 forum posts
20 photos

even if the reducer comes out in perfect condition, it's going in the scrap bin!

What a waste!

larry phelan 102/11/2020 09:41:30
1077 forum posts
14 photos

Would have been much simpler had there been a slot in the quill. What was the point in making something like that ?frown

duncan webster02/11/2020 09:53:05
3447 forum posts
63 photos

Even if it had a slot in the quill, the slot usually lines up with the tang on a drill etc, this adaptor doesn't have a tang as it has a clear hole through

Vic02/11/2020 10:21:00
2894 forum posts
8 photos
Posted by Gavlar on 01/11/2020 15:28:15:

Even if the reducer comes out in perfect condition, it's going in the scrap bin!

Good plan! smiley

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