Drill Press Runout

Mine is the orange Ridgid and has a JT33 (according to the markings on the chuck). Exact model number I have is the DP15501.

Manual says to just tap on the chuck with a mallet to get it off. I haven't even bothered trying that, I am going right for the wedges.

I am pretty sure I didn't use enough care cleaning the taper and chuck when I installed them. I know better now. I didn't then. Will see if I can clean it up a bit.
 
Yup, but they did use the word carefully! :eek:

REMOVING CHUCK
See Figure 30.
 Unplug the drill press.
 Open jaws of chuck as wide as they will go by turning chuck sleeve.
 Using a downwards motion carefully tap on the chuck with a mallet while slowly turning the chuck with your other hand.
 Remove the chuck
 
All,

I got some more time to work on this...and also got a heaver magnetic mount stand for my indicator. The other one was a small Noga and seemed like it would fall over easily with a dial indicator on it....worked fine with my DTI.

Anyways, I followed the above advice and marked the high spot. I rotated the drill bit in the chuck and tested again. The high spot moved seemed to follow the drill bit. This tells me the bit itself has most of the runout? Am I correct?

What should I test the runout with? I was thinking of turning a piece of aluminum in the lathe and using that as a test rod, but I m not sure if that would institute additional testing issues.
 
All,

I got some more time to work on this...and also got a heaver magnetic mount stand for my indicator. The other one was a small Noga and seemed like it would fall over easily with a dial indicator on it....worked fine with my DTI.

Anyways, I followed the above advice and marked the high spot. I rotated the drill bit in the chuck and tested again. The high spot moved seemed to follow the drill bit. This tells me the bit itself has most of the runout? Am I correct?

What should I test the runout with? I was thinking of turning a piece of aluminum in the lathe and using that as a test rod, but I m not sure if that would institute additional testing issues.
First indicate the chuck itself. Do it on the body of the chuck, the piece that has the holes for the chuck key. If that is spinning true. you can forget about everything above it. If not you will need to see what part(s) of the drill press have problems, as discussed above. If the chuck is spinning true, put a KNOWN accurate cylinder in the chuck. A new hardened steel dowel pin is cheap and suitably accurate, and is usually available at hardware stores. Check the runout of the pin close to the chuck jaws, and also farther away. If the chuck body is spinning true, issues with the chucked part are usually caused by worn or damaged chuck jaws, and/or from dirt and swarf in the chuck. The chuck can usually be disassembled to clean and lube it. The only real fix for damaged or worn jaws is to replace the jaws or the chuck. It will work a lot better if you can mount your indicator stand to the drill press head rather than to the table, more rigid setup. Steel attracts magnets better than cast iron does...
 
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If a drill press has especially bad runout and the bearing and chuck aren't obviously the cause odds are it's the quill to head fit. The set screw on the slide is only there to prevent the quill from turning, so its fit to the slot in the quill isn't a factor.

I have a cheap little Craftsman benchtop drill press for my basement (I have a floor press out in the shed) that is a combo drill + oscillating spindle sander. Because of the latter "feature" there's a lot of built in slop in the quill to head fit. Runout was not only visible but audible; I could lock the chuck up tight and and click the quill against the side of its bore in the head. It's the only press I've ever seen that could drill a hole both oblong and at an angle.

But I fixed it! I cut a thin vertical slot from the point where the quill enters up 0.5" past the final cast in ring that forms the bore; adding a 0.25" hole at the end to prevent cracking. I drilled a hole perpendicular across the head between these two cast in rings, being careful to keep the hole from passing into the plane where the quill would be (a slip for 1/4-20 bolt). With a hex cap screw slid in and a lock washer + nut on the end I could very carefully take up the slack. After reassembling the drill I slowly tightened up on the nut until the well oiled quill would just slide up and down smoothly. My oblong holes are now quite round and drilling is noticeably easier and more quiet. If anyone is interested I'll post a photo of the finished set-up. FWIW, I started the slot with a hacksaw but finished with a DeWalt 20v saber saw and a fine tooth blade (wish I'd started with it).

I didn't measure runout before (TIR=Horrible) and haven't measured it since because I'm planning on putting a nicer keyless chuck on it anyway. But I was very close to pulling the motor, pulleys and chucking the rest but now I'll keep it and am using it for important work. A lot of older premium presses had split heads for a quill lock but many also had the same takeup bolting arrangement.
 
My very old Craftsman "Commercial" drill press has a split head, push & pull screws. Seems like a good design. My first, third and 4th DPs, didn't have and none ran very well. If I ever get another DP it will have a split head or other means.
 
I have a Jet DP (Taiwan) that I bought about 20-25 years ago. The runout on mine was horrible, but I put up with it for years. I finally threw the old chuck in the trash and replaced it with
a quality keyless chuck about 10 years ago. It was a completely different machine after that.

Yes, exactly- get a decent integral shank chuck. Shars has an Albrecht-style that runs great at a good price. Drill press manufacturers keep point of sale costs down by including a useless chuck on what is otherwise usually a decent press. Borrow one if you can to test- you might not need to make any other mods to get the performance you want out of your little Ridgid.
 
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