Milling cutter going walkies?

[Majorstrain]

G'day

After I had a 20mm end mill go walkies in my R8 collet on some deep cuts in 4140 steel, I came up with this
No damage apart from the extra depth of cut that wasn't needed.

I marked a line with an Artline (magic marker I think you guys call them in the USA) on the cutter where it meets the collet.

If it starts to go walkies again, a gap will develop between the line on the cutter and the collet.

The reasons for the walkies in the first place,
One was oil on the cutter inside the collet and the other was just the depth of cut was too great.
The fact I was using flood cooling didn't help in early detection, It was only when the load on the mill changed that I knew something was up.

Hope this helps,
Phil

Oh, and if you take the cutter out of the collet you can put it back in and get the height close enough for none critical cuts without re-zeroing the z axis.

 

[justlesh]

A little trick to stop that walkie, mark the shank of the cutter good with that magic marker you have in your hand, let dry a minute and reinstall cutter. It works but not the best way, best way is to use a regular end mill holde.