Pillar Drill - Chuck wobble/Runout thread.

[Dissolve]

Hello,

I asked a question a while ago about a similar issue. But I think this is a topic a lot of people will have dealt with previously so I wanted to ask for some advice. I have acquired a Jet JDP 15 pillar drill, it is 2-3 years old but it looks hardly touched, no marks etc. It looks like a fantastic drill, but I am experiencing some noticeable runout/chuck wobble so it needs some set upo/attention before it's a permanent addition to my workshop.

I have removed the chuck/arbor and re-seated them using a firm strike of a mallet, it seemed to help slightly but I can't say it's greatly improved.. To start with, does anyone have some advice on removing dust/build up in the spindle taper? The chuck arbor is smooth/new looking, so I want to check the fit between the arbor and the spindle are perfect.

Assuming I clean out the spindle and this does not sure the problem, I will use a dial gauge and measure the wobble/runout of the spindle itself, there seems to be no obvious indications that a bearing has worn (I'd be very surprised) and there is zero side to side play between the quill/spindle or chuck.

Does anyone have some suggestions on how to find the cause of the runout/wobble and possible fixes? I have no other chucks/arbors to test with it but can anyone tell me how to separate the chuck and arbor to try re-fitting these components?

I might buy a new arbor and try replacing that before anything more expensive.

Thanks

 

[Dissolve]

UPDATE: I have measured the runout with a dial gauge and the chuck/bit measures .0010-15 which is pretty bad.

I took the arbor and chuck out and measured the actual spindle which was .0001 at most, and considering the arbor and spindle are both meeting well, I would like to try taking the chuck and arbor apart but I can't see how it is best to go about it?

If I were to replace the chuck and arbor.. do I just need to find an existing chuck/arbor with a MT2 taper as per the axminster spec sheet for the JDP 15?

 

[Claud1]

I purchased a jet pillar drill about 3 years ago and after about 2 hours work the laser packed in so I returned it and had to wait 4 months for its return only to find after a further 1 hours work the chuck kept falling off and when put back on had wobble that made it impossible to use. I have also got a Jet sander and from my 30 odd years experience I can honestly say it is the biggest load of dung I have ever bought

 

[Phil Pascoe]

One thousandth/ one and a half thousandth of an inch is "pretty bad" - how accurate did you expect it to be? Come to that how accurate would anyone expect a drill of that class to be?

 

[Dissolve]

One thousandth/ one and a half thousandth of an inch is "pretty bad" - how accurate did you expect it to be? Come to that how accurate would anyone expect a drill of that class to be?

Sorry that should have been 10-15 thousanths!

 

[wizard]

Its Chinese junk 3 years is near the end of its life put it on ebay

 

[Phil Pascoe]

Come on, Wiz - say what you really mean!

 

[wizard]

Come on, Wiz - say what you really mean!

I learnt the hard way and went out and bought nice new Chinese junk and spent most of my time making spare parts for it, i even had to buy a Boxford lathe so i could make parts to repair the Warco lathe. Now everything has been replaced with second hand.

 

[paulm]

I would guess that the chuck is a friction fit on the end of the morse taper, although it is possible it may be a threaded connection but I think these are less common, but could be wrong !

Assuming a friction fit I would hold the MT in a vice with soft jaws or a suitable lining, and use a length of wood with the end on the back of the chuck, at a shallow angle, and give it a bit of encouragement on the other end of the wood using a heavy mallet, club hammer or similar. Perhaps rotate the chuck and MT in the vice a couple of times while doing it and hopefully it will ease off rather than fly across the workshop and land on the floor !

If that doesn't work and you suspect it may be threaded, then I would still put it in the vice and try to find a stout right angle piece of metal that could be tightened in the chuck jaws and used to lever the chuck so that it unwinds, something like a t-bar handled large allen key for example. Not sure which way the thread would turn though.

If you succeed in getting the MT off you could then mount it in the drill (assuming you think you can get it back out again without the chuck to help) and measure the runout on that. If okay then you know the drill and the MT are okay and the problem is either the chuck or quite possibly just the seating of it on the MT. Reseating the chuck might if you are lucky be enough.

Cheers, Paul

 

[Dissolve]

Update: I purchased a new chuck. It's a Jacob's 35B 2 Morse Taper Groz arbor and the chuck is a threaded fit.

I'm not sure if my dial indicator's increments are hundredths or thousandths of an inch.. It's the exact same dial indicator in this photo:
http://www.phase2plus.com/details.asp?p ... tors&id=92

and the spec/model number is "900-102". Can anyone confirm that one increment on the dial gauge is one thousandths of an inch?

I'm measuring 4 increments of run-out on the bit when it's tightened in the new chuck. If one increment is a thousandth is that an issue?

 

[AES]

According to the table you linked to, your 900-102 DTI has a total plunger travel of one inch and the smallest graduations on the dial are each one thousandth of an inch - hence the QUOTE: 1" x .001" UNQUOTE: shown in the RH Descriptions column.

Krgds
AES