Drill press repair

[Chris Cramer]

The arbor on the end of the shaft of my drill press is in terrible shape and doesn't hold the chuck well enough to keep it at the center of the shaft. If you look at the original arbor in the first picture the arbor is part of the shaft, so it is a tapered shaft. In this case I will need to cut the arbor off the end of the shaft and weld a new jt6 arbor onto it.

 

[mbond]

do you have a lathe?

 

[BaitMaster]

do you have a lathe?

This is the #1 question. I had a drill press that was broken in a similar fashion, which was one of the main reasons I started looking for a lathe.

 

[Chris Cramer]

do you have a lathe?

Yeah I do have a lathe, and I tried using it to shape the arbor. I did get it straight, but the arbor didn't have enough material near the end to make contact with the chuck. Only about 1/8 an inch on the top of the arbor makes contact with the chuck which is what allows the chuck to move easily out of alignment. I could work further up the shaft and remove the narrow arbor, only, I'm not sure how much of the shaft can be spared.

 

[Darren]

can you true it up and add a drawbar? Is the spindle hollow?

 

[Chris Cramer]

The spindle is hollow. One long tapered draw bar runs up the quill through multiple pullies on top. I don't know if any of the drawbar could be removed and still remain inside the pullies when drawn all the way down.

 

[Chris Cramer]

I managed to shape more of the drawbar to fit more of the face of the arbor against the inside of the chuck to hold the chuck securely in place collinear with the draw bar.

 

[Ironman]

You may consider building up the taper with a mig welder and re- machining the taper. The taper needs to contact for the full length for accuracy and prevent slipping. It appears that the nose of the taper has been massacred and is undersize and you have no wiggle room to go up because of the bearing.
I would not expect the drawbar to keep things true the way it is.

 

[Chris Cramer]

The remaining amount of the taper that you see is excess taper where the rest makes full contact inside the chuck. The draw bar was long enough for me to cut off the end od the taper up to the point that made contact at the top of the chuck. From there I machined the draw bar to make full contact with the chuck. The top especially is tight, because the last half inch at the top of the chuck is straight and so I kept the top of the taper straight, about 1/32 wider, to friction fit it into the chuck flush with the straight part on the top with a hammer. I tested if it was centered by setting a very long and narrow drill bit on the very end, and found no wobble in the rotation.