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Happy
06-20-2004, 11:23 AM
I own a little Enco horizontal mill, made in Taiwan, and I would like to get the arbor out. I am a new at this, and I don't want to wreck anything, so any advice would help. I don't have a manual for it. Here are a couple of pictures of it, what I would like to know is the best method to take out the arbor. Also, what do you think the taper might be on this arbor. The drawbar is 1/2 by 20 tpi.
http://webpages.charter.net/wschall/arbor.jpg
http://webpages.charter.net/wschall/enco%20mill.jpg

Dave Opincarne
06-20-2004, 11:29 AM
That's a cute little machine, I've never seen a newer horizontal that small. Looks very useful. Have you tried giving the drawbar a whack with a deadblow to loosen the arbor?

Happy
06-20-2004, 11:30 AM
I will try and get the photos to show up.
http://webpages.charter.net/wschall/enco%20mill.jpg
http://webpages.charter.net/wschall/arbor.jpg

Happy
06-20-2004, 11:33 AM
yes, I whacked it lightly, I am unsure how hard I can hit it before I hurt something. the drawbar threads look like they are flawed from the factory, so I am hesitant to hit it too hard.

coles-webb
06-20-2004, 02:57 PM
Depending on what the drawbar is made of, it may not take much to damage it. I found out the hard way as I have a mill dill with a MT 3 which is not meant to be used as a milling taper or drawn in under pressure. I bent a couple of draw bars by hammering on them too hard and bending the thread. I now have a few spare along with most tooling having a straight shank to fit into a collet. If you don't have to take the arbor out, I wouldn't take it out. But if you must or just want to, use a steel bar with a brass end on it so the brass will deform and not damage anything. Ensure the brass is attached and not snug fitting as it may enlarge as you hammer on it. Wear googles and watch out for burrs on the end you hit (grind if needed). It may take a bit of pounding depending on the taper (A morse taper takes quite a pounding) and depending how long it's been there, rust, etc.. Also put a strap or something on the arbor so it doesn't go flying when it does come loose. When you do get it off take photos and measurements and ensure both male and female taper are clean before assembly. Start a book with all this and other information as our brain is usually full of holes when it comes to retrieving the info later. Good luck and let us know how it turned out.

Mike

quasi
06-20-2004, 03:27 PM
put a pipe over the arbor, then a piece of i/2" plate with a hole for a bolt to go thru. thread the bolt into the end of the arbor and tighten it up it will pull the arbor out of the taper.

I had to do this years ago on a small horizontal mill I had. I think it was a Burke, but I might be wrong. Ihope this helps you.

John Garner
06-20-2004, 04:17 PM
Happy --

The "drawbar" on many (if not most) NON-Bridgeport-type machines is a two-piece affair . . . the drawbar proper and a clamping nut. The drawbar is hand-threaded into the arbor thread and the clamping nut is wrench-tightened against the back of the spindle.

The standard way to remove an arbor from one of these machines is to loosen the clamping nut a turn or two and then rap the head of the drawbar to jar the arbor loose.

If the arbor is bound into the spindle, putting tension on the arbor using the method that quasi suggests will save a lot of beating, but even with the tensioned arbor I find that they usually want the drawbar smack.

If your machine's drawbar uses a clamping nut and you didn't loosen it, but instead used a wrench to unscrew the drawbar itself, you didn't really release the tension holding the arbor in place.

If that's the case, loosen the clamping nut and then hand-tighten the drawbar into the arbor while keeping the nut one or two thread pitches off the back end of the spindle before whompin' on the drawbar.

John

Happy
06-20-2004, 05:58 PM
John,

Is this the clamping nut? The picture shows the rear of the mill, where the drawbar enters.

http://webpages.charter.net/wschall/encopulley.jpg

[This message has been edited by Happy (edited 06-20-2004).]

coles-webb
06-20-2004, 06:47 PM
No you don't have a seperate clamping nut. There would be threads forward of the nut in your last photo and a nut on them to tighten against the back of the spindle. You will have to do as quasi, John or I suggested. The suggestion that quasi had has the least stress on the threads as long as you have the material on hand as the same as mine you have to have the material on hand. If you have a lathe or welder, go ahead and give it a good wack as you can weld a bolt on to replace damaged threads or cut new ones.

Mike

wierdscience
06-20-2004, 06:58 PM
I would put tension on it take a brass hammer and gently knock the hell out of it.

Go on and give it a good definate rap,just one good one will do it.The mill at work does the same thing,you have to get about 18" of swing going with a 16oz hammer to knock it out.

John Garner
06-22-2004, 09:30 PM
Happy --

I'll agree with the others, it looks like your drawbar is a one-piece affair. Still, it bothers me that the "protruding spindle end" has wrench flats milled onto it.

It's certainly possible that the wrench-flatted piece is both a retaining nut for the pulley and a spindle extension for the drawbar to butt against . . . but I'd sure be inclined to take it loose for a closer look before I began to wale on the drawbar.

John

Mike W
06-23-2004, 03:56 AM
I am trying to get an even larger arbor out of a brake drum lathe. I came across some info last night that said to tap it a few times as if you wanted to put it in and then try to tap it out. This has not worked so far.

I also read about cooling it with CO2 or a can of instant freeze spray. I have turned off a lot of metal from an old drum with the drawbar loosened. That hasn't worked yet. I have used PB blaster for days and days.

J Tiers
06-23-2004, 09:03 AM
That is one cute little mill, heavier than my Lewis.....I like it.

Anyhow, I would load it up with PBlaster, as a start. Let it sit a bit. Looks like it has had some rust, and that will loosen it.

If the rear view indicates that there is in fact a flatted area on the spindle rear, you might be able to put some torque on the arbor as you tap it. That may be a lot more effective than merely tapping alone.

The large area near the spindle is not used and isn't critical as to dimension. You can grab that with some crude tool like a stillson wrench if you have to. Of course a strap wrench would be more elegant.

I just got a chuck off a dividinbg head spindle with PBlaster and tapping, but I had to have the spindle out to do it. You probably don't want to do that, so you have to be careful not to brinnell the bearings by whacking things hard.