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View Full Version : Run out on the Nova DVR Drill Press



Bill Webber
04-21-2018, 8:09 PM
I just purchased the subject Nova DVR Drill Press. I measured the run out on the chuck using the usual method and got a pretty nice .0015. But then I grabbed the chuck and pushed and pulled it in the direction of the dial indicator and got more than .010 of lateral movement. So, now I'm not sure whether what I have is good or not. At best, doesn't this indicate the quill bearings are pretty loose? Thanks for any comments.

Jim Becker
04-21-2018, 8:16 PM
Check that the taper is seated properly and fully as a first step.

Bill Webber
04-21-2018, 8:55 PM
If the tapers were not seated properly, I doubt I'd be able to see .0015 run out on the chuck.

glenn bradley
04-21-2018, 9:43 PM
That is not necessarily correct. I have improved run out on more than one drill press by cleaning and resealing the arbor.

Bill Webber
04-21-2018, 9:55 PM
That is not necessarily correct. I have improved run out on more than one drill press by cleaning and resealing the arbor.

You folks are not answering my question. The measured run out using a 1/2 bit in the chuck is .0015 which I believe is quite satisfactory. I'm asking what I should expect when I grab the chuck and move it towards and away from the dial indicator. I'm getting something in the range of .010, indicating, to me, play in the quill bearings, right?

Rod Sheridan
04-22-2018, 12:49 AM
You folks are not answering my question. The measured run out using a 1/2 bit in the chuck is .0015 which I believe is quite satisfactory. I'm asking what I should expect when I grab the chuck and move it towards and away from the dial indicator. I'm getting something in the range of .010, indicating, to me, play in the quill bearings, right?

Not necessarily, it could be the quill moving in the head.

Older split type heads had the ability to hold the quill with less play................Rod.

James Baker SD
04-22-2018, 1:32 AM
I would think that variable density/hardness in a piece of wood, as the grain is drilled through, would push/pull on the chuck same as your hand did and thus I would guess that your hole accuracy would the 0.01 value. I could definitely be wrong on this, but it is what "my gut" tells me.

Peter Christensen
04-22-2018, 1:52 AM
The quill may have play between itself and the casting it slides up and down in. Just for grins bring the quill down to the bottom of it's stroke and repeat your measurements. The runout will probably be similar to when it is up but the side to side will be more. Contact Nova and ask then what the tolerances should be and what if anything can you do to correct it. If it in spec then you have to live with it. If out then they should fix or replace it.

Bill Webber
04-22-2018, 7:07 AM
Oh well, bad form I guess to answer my own post. Looks like I had my head up my butt. I forgot how a drill press is built. Tightening the quill lock eliminates the play I was fussing about. So, nice drill press. Sorry for bothering you folks.

Larry Frank
04-22-2018, 8:07 AM
The great thing about the Nova DVR drill press is that it has a split head and you can tighten to reduce quill sloop.

I get +/- 0.0025 when measuring on the chuck.

If I extend the quill full strike which is 6" , the run out is about +/- 0.003".

I could likely reduce run out by reseating the Morse taper chuck but would make little difference.

If I pull hard on the chuck when fully extended I can get 0.005"

The drill press was not cheap but is a great tool with the variable speed and low run out. I am really glad I bought it. I had a Jet floor model and the run out and quill slop were awful.

glenn bradley
04-22-2018, 8:26 AM
Oh well, bad form I guess to answer my own post. Looks like I had my head up my butt. I forgot how a drill press is built. Tightening the quill lock eliminates the play I was fussing about. So, nice drill press. Sorry for bothering you folks.

No bother here. I'm sorry I missed the area of the question. Glad you got it figured out.

Bill Webber
04-22-2018, 9:06 PM
Hi James.
Here's my 'gut' response to your hypothesis. It is only small bits that wander off in woods with hard and soft grain, like oak. Those bits bend and flex if they wind up in an out-of-square alignment because of the misalignment caused by hard and soft grain. The force they impart to the drill press quill is negligible. Larger bits cut better and are generally not prone to wander off.

So I don't agree with your premise that play in the quill affects the drill press run-out in any significant way. Just my 'gut' feeling. I see your logic, but I don't think it works. I'm not looking for an argument, it just doesn't generate any concern on my part. Drilling holes since 1956, best regards,
Bill W.

Keith Weber
04-24-2018, 12:49 AM
Bit wander will be a combination of bit flex and quill play. Small bits will definitely bend more than large bits, but big bits will wander, too, if you have play in your bearings or quill. You don't notice it as much because they don't flex as much. If you want to see a large bit wander, use a large twist drill in a hand held drill and drill through some sheet metal. Then put the shaft of the bit into the hole you just drilled and see how round and precise the hole is (or, rather, is not). With a hand drill, the flex in your wrist acts as quill play.