Advice On Removing Bent Arbor From Spindle

[JimDawson]

Hi JD, so I'm assuming you recommend removing the chuck first and working directly on the spindle with the dead drop? If the chuck is junk, I can't measure off that anyway.

I have never done it with the chuck removed. The spindle is so short that you wouldn't be able to do much with a dead blow. You need the leverage of the length of the chuck body to be able to move things around.

If the chuck is junk then the only way to solve the problem is to remove the chuck and check the spindle taper.
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[brino]

Hi Gavin,

Welcome to the forum!

I just wanted to jump in and make sure you caught the drift of this:

Lower your quill all the way down to see if there is a drift hole. If so you may have an adapter.

See the first method at this link:
http://www.ereplacementparts.com/article/3425/How_to_Remove_and_Reinstall_a_Drill_Press_Chuck.html
if you lower the quill and see an oblong window, then a flat wedge can be used to remove the chuck and arbor.

That is, if you have a female taper in the spindle and a male-to-male tapered arbor for the chuck.

-brino

 

[4GSR]

Back about 1980, dad bought two of these Taiwan drill presses off of a traveling tool truck that you used to see advertizing coming to town next week. Come one, come all and buy me out! Anyways,both drill presses were supposed to be alike until you started checking them very closely. Both had No. 2 MT in the spindle. Both had drill chuck with a fitted shank that was supposed to fit the taper. One was out about .008" the other was a little better. But get this, one had a slot for the drift key and other did not have one. The one spindle quill missed getting put on the mill and the slot put in. I don't remember what happen to the drill presses. They were sold off later in life.

As for removing a keyless chuck. There was one on a old drill press I wanted real bad that was fixing to get scrapped. There was enough room to get a adjustable wrench shoved in between the spindle quill and the keyless chuck. Tried to pop it off wouldn't budge by hand pressure. A 5 lb engineers hammer popped it off and flying thru the air.
I would shove the thickest open end wrench I could get in there and do the same. Give it a hard pop with a hammer and see if that would break it loose.
BTW, the spindle is probably running true, it's the chuck that is showing runout? Using my method may/could bend the spindle.

 

[Rootpass]

If you remove the spindle, Kieth Fenner had a video 2 years ago where he checks a spindle a viewer sent in and goes through the steps he uses to straighten one. I don't remember him using any real special equipment or anything. Might be fun to watch.

 

[GavinT]

I'm going to try and remove the chuck with a gear/bearing puller rather than hitting the chuck or the spindle from inside the chuck. I got a Yuasa chuck from ebay, cheap. Hope it's runs true.

If the Yuasa chuck is good and I'm still getting runout, I'll remove the quill and spindle. I'll be able to see if there's an arbor with a morse taper in the spindle, perhaps even with no slot for a drift key!

As the bearings are good with no spindle travel in the quill, I'll decide if I should replace the bearings once it's out of the head.

As I still think the spindle (or maybe arbor) is bent, as I get runout on the shaft at the top of the chuck, I'll try the dead blow hammer. If that doesn't work I have a buddy who can re-taper the Jacobs.

My fingers are now crossed that it does have an arbor (sans drift slot), in which case I'll get a new arbor.

Thanks again for the advice, y'all.

 

[GavinT]

Update. It's off! I used a 3 jaw gear puller on a deep socket through the chuck, just enough gap above the chuck to grab on to it. Bob was right,

The spindle ends with a JT3 taper, which is a Jacobs chuck taper. There is no Morse taper in the spindle on that drill press for an adapter.

As for the bend, it's 0.007 at the end of the spindle, and it hadn't moving in the slightest with a few good thumps from the dead blow. Bob, said

Depending on the length of the taper that does not now enter the chuck, there might possibly be enough metal left to true up the existing taper.

and there's 0.3" to that Yuasa chuck I got on ebay.

I have a friend with a lathe to re-taper, any idea on how much shorter the spindle will be, based on the .007 runout? (i only do "simple" math). He's suggesting threading it and making a JT3 adapter. He's certainly got the skills and a machine to thread. (He's building CNC in his garage), though I'm wondering if that's really a good idea to add complexity.

That chuck has crud and filings all along the jaws, so could do with a clean. Any advice?

Thanks!
G

 

[Bob Korves]

It is a precision job with a limited amount of material to play with. The spindle will probably be hardened, a little or a lot. If it is hard you will have to grind it. You really should grind it regardless, or you will not get full contact area. Trying to get the runout fixed without running out of length of the taper will probably only give you one shot to get it right. The bare spindle should be mounted between centers and the correct taper applied to the part or tooling slide, carefully confirm that the taper setup is correct and the bearing seats are running true, and then gently grind the taper using a properly dressed wheel. A lathe and tool post grinder can do the job, assuming the skills to do it right.

Edit: Before you do any of that, confirm that the runout is in the spindle, and where it is located. Make sure the spindle is not bent between the bearings.

 

[4GSR]

You have it torn down this far, take the spindle apart and confirm what Bob said to do and replace the bearings with good quality bearings. I bet those bearings have some issues, too.

 

[GavinT]

Thanks for the advice, Bob & 4gsr. I'll definitely check between the bearings, seeing as they act as a possible fulcrum when it bent, and also replace them. Round or roller prefered?

Any advice on cleaning the debris in the chuck?

 

[Bob Korves]

Put back the same part number bearings (or equivalent) that you take off. Don't buy the cheapest ones, get decent ones. They will have numbers on them. Most of those machines use standard, commonly available bearings. I can help if you give me the numbers on them.

As for the chuck, I have no experience with that brand, so I do not know how to disassemble it. If you are just trying to get the swarf out of it, blow it out with an air nozzle, use a little solvent to loosen the crud up if necessary, lighly oil the moving parts you can reach, and let it go like that until you can test it. With many chucks, BUT NOT ALL, you press the shell off the jaw end of the chuck. I would try to avoid that unless you find someone who has experience with that model and has instructions on how to work on it. You can easily ruin the chuck if you do the wrong things.