[gordo.hogan]

Hey guys i just started at a new company and im running a doosan puma 800 with the easy ooeration package cutting long shafts. On the turning side everything is going very well but i had to mill an external keyway the other day and for some reason the machine was cutting steps on the 1 side of the keyway. It was a 30mm wide keyway by 16mm deep and i was using a 12mm solid carbide cutter taking 5mm deep cuts each time using the y axis.

The program was made through the free form milling operation and i used m88 as the brake for the spindle.

I have no idea why i was getting steps on the 1 side of the keyway its almost like tool deflection or something but i dont think it was that as i didnt take overly big cuts and i was using a slow feed rate too.


I hope somebody can give me some advice because i am going to have to do it again soon and i really dont want to scrap another shaft.

Cheers!

[RCaffin]

a 30mm wide keyway by 16mm deep and i was using a 12mm solid carbide cutter taking 5mm deep cuts each time
And just how many kW were being pulled by the cutter?
That sounds wildly over-loaded to me. It's a wonder the cutter survived.
But then, I don't know how big the Doosan is.

Was the shaft FULLY supported at the site of the cut? Really fully?

Cheers
Roger

[gordo.hogan]

I managed to solve the problem. There was a problem in my program the tool change included a m42 code for high gear that subsequently unlocked the m89 chuck brake.