Alpine Mill/Drill

Our club has accquired an Alpine "Complex" Mill/Drill, Model DM 25 Circa 1980 (Graham Engineering), that I believe is one of the early Taiwanese imports. As far as I can see from the capacities stated on the front plate and the size and height of the ejector slot this machine should be 3 morse taper in the spindle, however it appears that the previous owner has inserted an open ended 3 - 2 morse sleeve, of the type that would normally go in a lathe mandrel, into the spindle. This means that any 2 morse drills inserted are not driven by the tang and also the ejector slot is too high up for them. We have tried to remove this sleeve but are unable to gain acces to the rear of it to apply any force on it due to the 1/2" drawbar hole and the tang slot for 3 morse sleeves.

Does anyone have a diagram of how these mill spindles are constructed or instructions so that we can strip it down and try to remove it, or alternatively can anyone suggest an easy way of getting this out without destructive removal?

That's an interesting challenge!

My first thought was to use a long curved drift through the drawbar hole and hope that it did not 'spring' too much when tapped with a hammer. Ideally you should put some support under the spindle to reduce the chance of bearing damage.

Another idea might be to make some sort of expanding nut that you can insert up the spindle past the top of the sleeve, then use a long bolt and tube to pull the adapter sleeve out. Sounds easy but I bet you will have fun!

Ian P

Hi There,

Could you machine up a solid bar to run up inside the minor ID of the open ended sleeve and cross drill it to accept a pin that can be inserted through the ejector MT3 slot. Insert the solid cross drilled bar and then the cross pin and locate against the back of the open ended socket. Then use either a sleeve/drawbar to pull out, or a simple sliding hammer and a few knocks might pull it out?

Neil

Hi Gavin,

Here is one suggestion. Make an oval plate about 6 mm thick with its larger axis just less than the outer diameter of the adaptor sleeve and its smaller axis just less than the hole at the top end of the adaptor sleeve. Drill a small hole in its centre. Now thread a piece of string or wire down through the spindle. tie the plate on the end of the string. Hold the plate so the larger axis is vertical and pull it up through the sleeve. When it comes out the top of the sleeve it will hopfully drop across the top of the sleeve. You should then be able to drop a bar from the top to tap it out. I suggest squirting penetrating oil down the spindle a day or so before you try this. Heating the bottom of the spindle with a hot air paint stripper may also help. A variation on this idea is to tap the hole in the plate and try to screw a threaded rod into it from the bottom to draw the sleeve out. I have one of these sleeves so I will measure it tomorrow.

Les.

DM25 sounds like any other RF25 Mill/drill, i have a Clark.

As above no need to strip down and can only assume its the short non tanged type of MT3 inserted that the drifts wont dislodge. I have a few knocking around some where i wont use, cant remember if tops threaded either.

Quill lock on and give it a bash through where the draw bar goes. I wouldnt use the original drawbar as it may damage the thread, so something like 10 or 12mm round.

If you can attach an old but servicable 8-10mm drill securely to the 2mt tang then do some (careful) work with it.

Drill a reasonably deep hole in a lump of scrap, then lifting the drill slightly and moving the drill slightly from side to side like it was a slot drill the vibration will probbly free mt2 taper from the mt3 taper

That sort of thing, the main thing is that the tooltip is (slightly and carefully)unsupported and you induce tool vibration(asking the machine to do too much work) on an unsupported tool tip

The tooltip only needs to be a fraction above its pressure point, and as the morse taper releases the mt2 will spin inside the mt3 taper

I've found that morse tapers are totally useless once they get a bit of work vibration and have no supporting pressure on the tip of the tool.

The morse taper loosens up, no matter how tightly it's been fitted.

....unless of course...he's superglued it in...lol

Edited By Ady1 on 26/02/2012 23:17:29

Which is why they have drawbars.

Morse tapers are too dangerous without a drawbar

....which kind of makes you wonder whether he did something to make sure that that mt2 fitting never came out...

Superglue...or a hole, drilled and pinned...

I'd have a careful look at it before getting out the lead mallet.

Hi

If the 3MT /2MT sleeve protrudes below the end of the spindle a little you could turn a blank disc the diameter of the MT sleeve, weld it to the end of the MT sleeve, then drop a bar down the spindle bore and tap it out.

Or

Turn a piece of bar to 2MT and loctite it into the sleeve, place a bar down the spindle bore and tap it out.

Nigel

Edited By tractionengine42 on 27/02/2012 03:01:32

Hi if you are after a manual go to grizzly.com pick out the one that looks like yours and you download a manual free they have been importing chinese machines for many years and writing the manuals for them.

Bob

Hi

Thank you to all who have replied so far and thanks for the helpful and varied suggestions. I have downloaded the parts list and diagram suggested by Springbok - very useful. I have already tried using a bent bar down the drawbar hole but can't angle it enough to catch the end of the sleeve. I will give some of the other suggestions a try starting with the least destructive and let you know how I get on in due course.

Regards to all

Gavin

Hi

Just to update everyone I tried the excellent suggestion from Les Jones using the threaded oval plate.

I used an endoscopic camera (bought from Aldi for boiler inspection work) to position it and a long 5/16" Whit setscrew with an extra nut and large washer on it below the spacer rings (old ballrace inners) bearing on the spindle nose. I held the bolt head with one spanner and tightened the nut up with another. It worked perfectly and the sleeve turned out ot be a cut down drill sleeve rather than a proper lathe mandrel sleeve.

Kind regards

Gavin