Drill press run out...am I doing it right?

[Fyrme]

Ok, I was cleaning the garage up today and during one of my sidetrack moments, I finally decided to check the run out on the old Craftsman drill press I bought. I broke out the dial caliper and set it up. I chucked up a old wrist pin I had on the bench and turned the chuck by hand. These are the results......

 

[spongerich]

If I'm reading your indicator right, that's 1.5mm (or about .055") out. That seems like a lot of runout. Does it wobble noticeably when you run it?

You might want to check again, but instead of turning the chuck, turn the motor pulley... also try grabbing the pin and gently push it towards and away from the indicator. If your bearings are worn you might see a lot of movement side to side.

 

[91bronc300]

That indicator is reading 0.15mm or 6 thou. I'd be happy with that on an old drill press.

 

[Outlawmws]

What he said: ^^^^

Is the wrist pin straight?

Is the chuck clean?

If you indicate off the spindle or the chuck do you get similar results? (Helps tell you where the runnout is)

Does it give similar results when the quill is in the up position?I

 

[Fyrme]

It the first Tim I have used the dial, but according the the legend on the face that should be .15mm.

 

[Fyrme]

Outlaw, that's the only test I've done. I'll revisit it soon. I just wanted to be sure I was doing it right. I have a habit of getting side tracked. I'm just lucky I didn't dive in to trying to make it perfect. I'd have never gotten that wall cleaned up. Lol

 

[larry_g]

A couple of things to try here. Remove the test pin and rotate it 180* and try again. Try tightening the chuck on the three different holes available. Try it with the quill fully retracted. grab the quill and force it side to side and measure that movement. Try a few different things to see what happens. One set up will not give you the whole picture. If you have a micrometer measure the pin your using at a couple of different places and rotations. You may find it a bit egg shaped.

Also it looks like you had little to no preload on your indicator. Did you set things up so the pointer rotated a bit before you set the outer dial to zero?

lg
no neat sig line

 

[A_Pmech]

Run the quill up into the housing completely to minimize deflection of the quill, which will alter the true reading. Also, make sure your indicator has enough over travel as Larry said.

If the runout figure is still .14mm then you have nothing to worry about. That's very respectable for a homeowner / maintenance drill press and a plain bearing chuck.

 

[Fyrme]

Alright, thanks guys. I will look into it with more depth. I'll check my other press to at the same time. And yes, when I set it up, (forgive the lack of my proper vocabulary here) I set the plunger thingy against the wrist pin with the fine tune knob and depressed it slightly, thenrotated the dial face to zero. So it did have a load on it. Is that correct? I'm glad that the .14mm is acceptable reading. I questioned it the first time I used the drill because it had some wobble. But I think it was a combination of a bent drill and a wobbly base.

 

[zkling]

Run the quill up into the housing completely to minimize deflection of the quill, which will alter the true reading.

X2, and tighten the quill slop adjustment so you are not adding to the measured deflection. Also how are you turning the spindle? Try turning the motor pulley, that way you won't induce any additional load into the spindle. When installing the pin, give it a slight twist before final tightening in the chuck to make sure it is seated properly. Finally tighten all 3 chuck holes, yes it can make a difference.

Anything under ~0.005" (0.125 mm) TIR is good. Ideally under 0.003", but...

BTW, congrats on owning a metric indicator.

 

[Fyrme]

BTW, congrats on owning a metric indicator.

Thanks, I mean, I think.....
The price was right and it was in great condition. Although, I sometimes wish I was fluent in the metric system. It is Sooo much easier I think.

 

[zkling]

Thanks, I mean, I think.....
The price was right and it was in great condition. Although, I sometimes wish I was fluent in the metric system. It is Sooo much easier I think.

I bought one real cheap on ebay once a Brown and Sharpe best test, my favorite indicators. It is ~ a $250 DTI and ended up being <$10 shipped. Probably because most folks in the states don't like metric measuring tools.

I just could not get use to it. After messing up multiple parts, I ended up giving it to a friend of mine. He loves it and is obviously much smarter than I am. No more metric indicators for me. Calipers and mics are one thing, but I just can't do metric indicators.

If someone says something if off X# of thousands, I can visualize that real easy. If they say it is off 0.X millimeters, I usually have to reach for the calculator.

 

[1982fxr]

roll your pin on thick glass to see if it's straight...