Depth of cut tolerence

[lwells]

Simple 2d pocket. .05 step down,.01 finish cut. From 0 to -.395. Mastercam calculates the step down in even amounts but for some reason in larger arc moves it calculates a .0001 varience in the z depths that is being posted to my code as a three axis move. My machine is not capable of three axis moves and stops. Need to eliminate these z moves.

[gcode]

Analyze the pocket chain and make sure

the chains are really 2d.

If they are lines, arcs or splines extracted from

solids or surfaces, one on them may not be quite flat

[lwells]

I analized the contour and z for all lines is the same.If I go from 0 to -.935 step down is output to 4 place decimal and the .0001 varience is output in the arc move. If I start at .015 to

-.935 steps are even and I get a 3 place and all is good. It seems is that if overall depth does not divide to a equal amout MC calculates the steps to a .0001 tolerence. For this machine +/- .0002 is the best I can do. Would like it to stay 3 place if possible.

[ken wong]

check tolerance in your control definition

[lwells]

I tried to change tolerance in the control definition to no avail. Heres a sample of the code.

N140 G1G40Y16.8354

N150 Z-.1983F10.

N160 G41D26Y18.3354F30.

N170 G3X-4.3354Y14.Z-.1984J-4.3354

N180 X0.Y9.6646I4.3354

N190 X4.3354Y14.J4.3354

N200 X0.Y18.3354I-4.3354

N210 G1G40Y16.8354Z-.1983

I have to calculate a start position that forces a three place decimal. In this case 2.

N140 G1G40Y16.8354

N150 Z-.16F10.

N160 G41D26Y18.3354F30.

N170 G3X-4.3354Y14.J-4.3354

N180 X0.Y9.6646I4.3354

N190 X4.3354Y14.J4.3354

N200 X0.Y18.3354I-4.3354

N210 G1G40Y16.8354

N220 Z-.26F10.

This .0001 variance is messing with my code.

Could this be a post issue? Seems to only do this in arc moves.

[Verndog]

Try changing top of stock by .001 or a number that makes it come out in .001 increments. Also if the machine wont allow it, in the control definition manager, under arcs, select no helix allowed (under helix support)

[lwells]

No go. I'm going to switch machine defs and see what happens.

[Brad Lisle]

check your axis combos in machine def.

[ajmer]

try changing the NC PRECISION from 0.0001 to 0.00001

this is in the contol def

[lwells]

No dice. I switched to a different machine def and the z depths posted a 4 place decimal but the arc moves were split in 2 insted of 4 and no extra z moves were posted. In the above code I am milling a circle. Unfortunatly it's an old machine and stops at each quadrent so all arcs have to break at quadrent. I've tried changing control def tolerances,config,and even post settings with no effect to step down tolerance. Thanks for the help so far.

[lwells]

P.S. This machine rejects all 3 axis moves else I don't think it would be a problem.