[rrbmachining]

I have not had to use this before so please excuse my ignorance of this feature. I am milling some pockets for bearings to sit in, so want a good fit. I have been using a 10mm slot drill to open out a 28mm pocket, which has come out undersize. My cam system has created offset geometery so now I want to use the tool wear feature of the control to open out the pocket to a good fit. I take it the best way is to use a G41 command and enter something in the tool diameter coloum of the offsets page. Question is what do I enter for this, is it the difference between my measured pocket and the finished size, and if so is a positive or negative value.

Any help would be appreciated

[Geof]

Enter zero in the diameter column and then use negative values in the wear column.

[rrbmachining]

Thanks Geoff, if I use the tool wear coloum do I still need to program G41 or G42 ?

[Geof]

Yes. Wear only works when compensation is active. Are you sure your cam program does not put the G41 or G42 in? I don't use cam but I thought many times it did the diameter correction in the code but put in the tool compensation commands (with a diameter entry of zero) so that wear could be used.

[rrbmachining]

When i post processed the part there was no G41 / G40 codes in it. I have now found the option in my cam (Camworks) to turn these codes on to allow wear compensation to be used. I think just to get this part done I will edit the code just putting G41 in for the final finish pass only, and fiddle with the wear figure to get a good bearing fit.

Thanks Geoff for you help

[cwcw]

In camworks are you using a contour mill to finish your pocket? If so go to the NC tab and look for cnc finish parameters and turn cnc compensation to on and turn toolpath center to with compensation. If this doesn't give you the correct code you are looking for then your post needs to modified.

[jason roy]

The figures you enter into the geometry and wear columns also depend on if the code spit out is programmed to centre line of tool, or tool edge..