Repair, replace, bent drill press spindle

buffdan

buffdan

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So as I was disassembling my nice Craftsman 15" drill press to give to my nephew.. I dropped the head, and it crashed to the floor. :mad:
One cracked motor end cover, and bent spindle nose (.090 out of round).
The motor is shot.. Need to replace.

The spindle nose is badly bent. I was going to attempt to straighten spindle the nose, but upon disassembly, I discovered that at the factory, they messed up and drilled 2 - 90 degree opposing holes for roll pin (picture attached), which the collar uses .. So that area is compromised

Now I have to decide on making new spindle, or stubbing the nose portion (maybe 6")
Suggestions?

I have equipment to redo the spindle nose/taper... But I have never done splines.. Which I think would be a fun challenge.

Anyway, I have some 5/8 4130 to stub the nose.
What steel do you suggest if I decide to make new spindle?
Also, stubbing the nose, center screw between pieces and red Loctite sufficient, or small roll pins on both end of stub joint as well?

Thanks!
Dan


20221016_121004.jpg20221016_121013.jpg
 
Last edited:
Steel, 4140.

This old Tony has a video on cutting splines without a spline cutting tool (only a slitting saw).
Needs spindexer or horizontal rotary table.
 
Argg! Nasty accident. What about straightening the existing spindle? Seems doable if you have a press
As the old saying goes, metal can have any shape you want if you are skilled enough
(and any shape BUT the one you want if you are not)
-M
 
Thanks Mark, yes, I said more than Argg. :)
I was going to, but when I saw the double roll pin holes.. I thought that to be a compromised situation.. Though those holes are within the inside of
the collar. Hmmmmm, maybe I should try that first 1665946329959.png
 
I'd go for trying to straighten the existing one first too. I mean, what's to lose? If it doesn't work you still have to make another, but if it does you're ahead of the game on many fronts.

Although this may seem a trivial comparison I made a similar repair to the main shaft on a Singer 306 sewing machine. It too had been dropped on it's end (I suspect) and the shaft was kinked almost exactly like yours. I figured what the heck and gave it a shot. By some stroke of luck I managed to get that darn thing within a hair and it was back in the machine with no discernable runout on the handwheel whatsoever. Aside from just being a nice machine to run I love using it just because the repair worked out so slick. I did a short post on it here if you want to see how I went about it..

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Finished (for now) the demagnetizer. I can report my version does work. It is a lot better than the Wiha tool commonly sold. The Wiha mag/demag tool leaves a lot more residual magnetism. If the delrin were to spin relative to the aluminum, I was thinking of machining a slot in the delrin and...
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-frank
 
buffdan said:
So as I was disassembling my nice Craftsman 15" drill press to give to my nephew.. I dropped the head, and it crashed to the floor. :mad:
One cracked motor end cover, and bent spindle nose (.090 out of round).
The motor is shot.. Need to replace.

The spindle nose is badly bent. I was going to attempt to straighten spindle the nose, but upon disassembly, I discovered that at the factory, they messed up and drilled 2 - 90 degree opposing holes for roll pin (picture attached), which the collar uses .. So that area is compromised

Now I have to decide on making new spindle, or stubbing the nose portion (maybe 6")
Suggestions?

I have equipment to redo the spindle nose/taper... But I have never done splines.. Which I think would be a fun challenge.

Anyway, I have some 5/8 4130 to stub the nose.
What steel do you suggest if I decide to make new spindle?
Also, stubbing the nose, center screw between pieces and red Loctite sufficient, or small roll pins on both end of stub joint as well?

Thanks!
Dan


View attachment 423703View attachment 423704
Click to expand...
Sounds like a great project.
I’m in……
 
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