I’ve got a Micro Mill and I don’t understand why the mill has so much vibration with collets and the drill chuck. The headstock has 0.001” of vibration when I hand turn it with a dial indicator hooked up. When I get a collet with an end mill on there its vibrating 0.005” at its tip. When I get something on the chuck attached to the mill were up to 0.015” of vibration. So by the time I get a drill bit or longer end mill on there its really moving, about 0.05” of vibration or so.

I thought all the vibration was caused by the headstock, but after I bought a replacement headstock and hooked it up to test it out, I realized that it both headstocks produced vibration, and the same amount of vibrations.

I was under the impression that these things were accurate, is this supposed to be accurate?

how are you messuring you "vibration" (I think you actually talking about radial runout) if its .001 thats probably what the chinees think is good for an export ;) but .05" on a drill, I would think you drill chuck is wacked! (which unfortunatly isn't that uncommon in the cheaper stuff).

You probably need to isolate what the problem is. If you could get a ground piece of stock with a known "good" collet you might be able to get a good reading. After insertion into the spindle check the runout then mark the shaft and loosen and rotate 1/4 turn and check it again. Go all the way around and compare readings. this will tell you if your spindle is the problem or the collet/shafting.

hopefully ;)

yup, sounds like a case of very bad runout. First thing I would look at is the collets.

It’s an American made micro mill from http://www.taigtools.com/

As far as I can tell I probably do have a bad collet closer and a bad chuck, don’t I have just all the luck?

Well what bothers me is that both of the headstocks, the one that came with the mill and the one we got as a replacement read exactly the same on my dial when I had it setup and I spun the spindle by hand with the dial The funny thing is I have two spindles that had the same reading, so if I did get two bad spindles in a row I’d be very surprised.

how are you messuring you "vibration" (I think you actually talking about radial runout) if its .001 thats probably what the chinees think is good for an export ;) but .05" on a drill, I would think you drill chuck is wacked! (which unfortunatly isn't that uncommon in the cheaper stuff).


A little off subject but (I just notice this in your posts) it's spelled "Chinese" ;)

A little off subject but (I just notice this in your posts) it's spelled "Chinese"

I make thangs, neever said I wer good a spealing! ;)

I think if there is a condition of Dislexia (closest approc to spelling) that affected typing I definitely have it! :D

i noticed that i had a bent drawbar and that was throwing off my collets and making them wobble.

Several things (sorry I'm so late in replying, It helps to put "Taig" in the subject header)

What are you using to measure runout? And how are you measuring it. Measure runout with a test indicator bearing on the internal taper.

This sounds odd, but are you sure that the collet is positioned correctly? Some people have put them in upside down.
Check the collet for burrs.

Measuring off of an endmill is generally error prone, better to measure off a chuckedup dowel or gage pin.

How did you tighten the collet closer?

and make sure the taper, collet and endmill are clean. Don't ask me how I know that......