Last Pass of profile

[edwan]

I cant seem to get the "last pass" part of a profile cut to work. If I cut a profile and leave a , say .05 allowance, then I select "Last Pass", 0.0 allowance, reverse direction.
It does not do the last pass cut.

Surely this is operator trouble. I have been here before.
Any suggestions?

[Bob Reda]

If I understand you correctly, if you put in 0.0 as last pass it won't do anything. I usually put in .0025 and it puts a very clean edge on.

Bob

[edwan]

I am misunderstanding the operation. I thought leaving a profile allowance of say .05" meant that the cut left .05" uncut, which a Last pass of "0.0" would then cut to the final dimension.
Doesn't this mean that the final size is off by the last pass dimension?
I have read the manual and the spot where my head bangs the desk is getting worn.

[Adrian]

The allowance is how far "off" from the vector every pass apart from the last one is. The last one is always 0 automatically otherwise the part would be the wrong size.

It sounds like you might be using the Allowance Offset in the Machine Vectors section as well as the Allowance in the Last Pass. They are two different things. The former adjusts all passes to allow for fine control of sizing parts etc.

[edwan]

I got it that time. That make sense. Thanks for the clarification.
Feels good not to keep damaging the desk.