[McFrey]

Hello

I am new here and I urgently need help for my upcoming task. (controller 840D 3 axis vertical)
I have to process a few parts in which I have to mill an ellipse.
The only imaginable possibility would be immersing into the material with a radius cutter and run a radius in Z minus direction ..That works quite well so far. Only I overlooked the necessary cutting radius compensation. After I milled the first part it was clear to me. I run the radius solidly and with the tip of the radius cutter.

I need special help for the compensation for the radius miller in Z-direction.
In the tool memory I am able to store 3D tools without problems.
But how can I describe a contour in Z/X direction?

Processing the radius in a solid manner would distort the result towards the outside.
The dimensions: Radius 12.5 (the radius cutter has the same) on radius 28.5; depth:10.5

Many thanks in advance

[hapo]

Hello Mcfrey
Welcome in the CNC arena!
In the sketch that you posted I don’t see an ellipse but a radius of 18,75.

If the ball cutter diameter 25 is measure at the tip, and the neutral point lies at the middle of the cut-out and the upper edge of the work piece, then the following code should work:
T="BALLCUTTER_D25" D1
M6
S2000 F500
G0 X-21 Z4 M3
G18
TRANS Z=-$P_TOOLR
G111 X0 Z18.25
G1 AP=220 RP=28.75 G41
G3 AP=300 RP=28.75
G1 Z10 G40
G0 Z50
M5
TRANS
G17

[McFrey]

Ok the radius is correct, the ellipse is created automatically.
I understand the code apart from : TRANS Z=-$P_TOOLR.
Usually I mainly program cycle controlled-it’s easier for my co-workers.. They will hit me when I come along with G codes again. But your solution sounds very plausible. I will try it out tomorrow and post the result.
Thank you a lot.. its save a lot of time for me and a potential disgrace too! wink.gif
Regards
Michael

[hapo]

TRANS Z=-$P_TOOLR

It’s a zero offset onto the cutting radius midpoint.
$P_TOOLR is the cutting radius that was entered in the tool list.
Only like that the WRK works in G18....