Craftsman 100 drill press run out.

[1967 R502]

So I’m wrapping up a restoration on a 1949 craftsman 100 drill press. There seems to be quite a bit of run out.

~.006” measured at the spindle taper and ~.02 measured at the bit.

Either of these measurements seem to be too much to me.

1. Are my expectations too high?
2. If this is in fact too much run out how do you adjust for it?
3. Later presses often have an adjuster bolt which will alternately squeeze the head or the quill to adjust for this, but the 100 has no such adjustments.
4. I’ve tried reseating the chuck in several positions, which no change to the overall run out, so I’m pretty sure the chuck and taper are ok. Of course this would not do much for the run out at the spindle.
5. Belts are level from to back and side to side.
6. Quill bearings are new.
7. Pulley bearings are repacked.

Suggestions?

 

[laser3kw]

that could be the runout in the Jacobs chuck itself. They aren't made to be a precision holder.

 

[1967 R502]

Perhaps, but is the .006” runout at the quill acceptable? It seems like a lot to me.

 

[Cruzan80]

Try taking the belt off to eliminate the pulley bearing as a possibility of movement. If it goes doen, you know the pulley bearings need replaced (vs repacked). If it is the same, then it is your quill/spindle.combo.

When you say the taper, are you measuring with the chuck off? Are you using a drill bit, or a precision dowel pin? Made sure the chuck jaws dont have any burrs and it is sitting centered and tightened at all three holes?

 

[gorilla]

What type of bearings are in the quill? If they are tapered roller bearings you may need to tighten up the pre load. if they are ball bearings you most likely ave a bent shaft. This is assuming that all the bearing fits are tight. That chuck looks like a Jacobs it should run out no more than about .003" rebuild kits with new jaws should be available,

 

[1967 R502]

Try taking the belt off to eliminate the pulley bearing as a possibility of movement. If it goes doen, you know the pulley bearings need replaced (vs repacked). If it is the same, then it is your quill/spindle.combo.

When you say the taper, are you measuring with the chuck off? Are you using a drill bit, or a precision dowel pin? Made sure the chuck jaws dont have any burrs and it is sitting centered and tightened at all three holes?

When I say taper, yes, the chuck is off. As noted, I am using a drill bit. It can be seen in the photo. I don’t have a precision dowel.

Chuck is fine. No burrs. Tightened on all 3 holes

 

[1967 R502]

What type of bearings are in the quill? If they are tapered roller bearings you may need to tighten up the pre load. if they are ball bearings you most likely ave a bent shaft. This is assuming that all the bearing fits are tight. That chuck looks like a Jacobs it should run out no more than about .003" rebuild kits with new jaws should be available,

They bearings are not tapered. All ball bearings.

The spindle isn’t bent. Unless it got bent after reinstalling . I am more concerned that the quill has enlarged the opening in the head over the years and there is no way to adjust for this as in later drills. At least none that I know of.

 

[Cruzan80]

When I say taper, yes, the chuck is off. As noted, I am using a drill bit. It can be seen in the photo. I don’t have a precision dowel.

Chuck is fine. No burrs. Tightened on all 3 holes

Have you tried other drill bits? The difference between the taper and the drill bit seems excessive, so had suggested a ground dowel pin as a control.

 

[Leviton]

It looks nice.

 

[Zeus36]

They bearings are not tapered. All ball bearings.

The spindle isn’t bent. Unless it got bent after reinstalling . I am more concerned that the quill has enlarged the opening in the head over the years and there is no way to adjust for this as in later drills. At least none that I know of.

Easy to shim any opening for a tighter fit - as long as we are talking machines.

 

[gorilla]

Put your mag base on the quill and measure the run out of the spindle relative to the quill. if that's ok use your indicator to look for lateral movment between the housing and the quill. You should do all this with the belt off. Jamming a drill bit can often damage the chuck jaws and the taper on the end of the spindle.

 

[1967 R502]

I’m not sure how you’d shim the quill opening in the head. I would imagine you’d have to strip the head, Hard chrome the opening and the grind it to spec on mill.

If you know of some other way to fasten in a .004” ringed shim, please let me know.

The common solution is to put a vertical cut in the head with a cross bolt running across. The bolt tightens the head together thereby taking up the slack/overbite in the quill hole. Lots of drills are now built that was from the start.

Realistically this is waaaay too much effort and cost for such a drill as the 100.

Easy to shim any opening for a tighter fit - as long as we are talking machines.

 

[JZiggy]

Try marking the bit at the "high" spot, turn it 180*, and see if it moves with the bit. Then try another bit or get a 1/2" linear shaft on Amazon for a few bucks and use that as your precision shaft to measure against.

20 thou is a lot of runout but 6 thou at the taper is not bad. My bet is that the excess runout is in the chuck.

 

[1967 R502]

I’ve tried that with the chuck. No difference.

 

[Zeus36]

I’m not sure how you’d shim the quill opening in the head. I would imagine you’d have to strip the head, Hard chrome the opening and the grind it to spec on mill.

If you know of some other way to fasten in a .004” ringed shim, please let me know.

The common solution is to put a vertical cut in the head with a cross bolt running across. The bolt tightens the head together thereby taking up the slack/overbite in the quill hole. Lots of drills are now built that was from the start.

Realistically this is waaaay too much effort and cost for such a drill as the 100.

​

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Use a metal retaining compound to affix the shim in place.

Try checking the runout with the quill lock engaged. That negates the clearance and quill fit in the head.

 

[Jim C.]

I have the same drill press. Mine is a 1948 model that I got in unrestored, relatively unused condition. That being said, it still had some runout. I took the machine apart, cleaned it up and lubricated it where necessary. It still had some runout. Now I know you said you’re tightening the chuck using all three holes. I was doing the same thing. Still had some runout. What I eventually figured out was that on this particular machine I had to be a little more particular about tightening the chuck. I tighten all three holes to approximately half of their full torque. Then I go around again and tighten each one to about 90%. Then one more rotation to 100%. I know that sounds like a PITA, but the whole process takes less than a minute, and whatever is spinning in the chuck has virtually no runout.

Jim C.

 

[1967 R502]

Use a metal retaining compound to affix the shim in place.

Try checking the runout with the quill lock engaged. That negates the clearance and quill fit in the head.

Thanks. The quill lock is already engaged as you can see in the picture above. So all measurements are made that way.

Not sure what you mean about metal retaining compound. Gluing a strip of metal to the inside of the quill seem likely to far exceed the .006 (really .003 as it is a circle) variance I am looking to eliminate.

 

[1967 R502]

I have the same drill press. Mine is a 1948 model that I got in unrestored, relatively unused condition. That being said, it still had some runout. I took the machine apart, cleaned it up and lubricated it where necessary. It still had some runout. Now I know you said you’re tightening the chuck using all three holes. I was doing the same thing. Still had some runout. What I eventually figured out was that on this particular machine I had to be a little more particular about tightening the chuck. I tighten all three holes to approximately half of their full torque. Then I go around again and tighten each one to about 90%. Then one more rotation to 100%. I know that sounds like a PITA, but the whole process takes less than a minute, and whatever is spinning in the chuck has virtually no runout.

Jim C.

Hi Jim- I'd be curious as to how much runout you were experiencing at the taper? Is .006" within your experience? My drill was in very good shape, but obviously used consistently by first a father and later a son, both of whom were professional carpenters. They took good care of it. It had been rebuilt at least once as the bearings in the drill were not original and it had a repaint at some point.

 

[whateg01]

Runout is not adjusted by anything. The clamp you are talking about is often used for removing slop in the quill, but is more often used as a quill lock. Don't confuse the quill and the spindle. The spindle spins. The quill is the part that slides up and down in the head. My spindle had a very tiny crack at the top of the taper. Hard to see, but could be felt with a fingernail. I started making a new spindle, but got distracted, so it is sitting in a box for now.

Is the runout the same all along the taper? Or does it get worse at the end? If it gets worse in the ~5/8" of taper, it will get worse yet in the couple inches of chuck length. If it's the same all along, then the bearings are more likely the culprit and additional runout is in the chuck.

 

[Cruzan80]

If the quill lock is engaged, there is nothing wrong with the headstock/quill interaction. This is due to the fact that if they are locked, by definition, they cannot move.

As someone just said above, the quill doesn't spin, only the spindle. So something is causing the spindle to not be straight.

 

[Jim C.]

Given the fact that this particular model drill press was a “quest machine” that I was looking for for years, I was sort of disappointed when I saw that it had noticeable runout. I have no idea how much because I didn‘t measure it. With a drill bit chucked, it was plainly visible to the naked eye. It really bugged me. So after all the second guessing and disassembly and reassembly I thought I’d try to really take care when tightening the chuck. That‘s the only thing I hadn’t tried. Well, that’s literally all it took. Now I had some slightly different circumstances. My machine was 100% original and unused for decades. It was still on its original shipping pallet. You’re working with a machine that someone else rebuilt.

Jim C.

 

[exmaxima1]

i've owned a number of those vintage CM presses and never found them to be especially tight. I think they were intended for DIY users and the bearings got sloppy pretty fast. If you want a more precise DP look for a vintage Delta or Clausing. I wouldn't invest too much into a Craftsman DP