CIRCLE1 and CIRCLE2 being skipped in a program

[ScottB]

I am having problems with CIRCLE commands being skipped or ignored. I have a linear move followed by a complete circle, the following is a portion of the program

 

N34F200LINEARX128.39400Y10.00000

N35F100CIRCLE2X128.39400Y10.00000I130.00000J10.00000

.....

N69F200LINEARX128.44872Y9.58434

N70F100CIRCLE2X128.44872Y9.58434I130.00000J10.00000

 

The circle on line 35 executes but the circle on line 70 does not. If I move the start point around the circle it works when it is at 180°, 210°,240° and 270° but it skips the circle at 195°, 225° and 255°.

 

We are using absolute vector mode for I and J, ABS(I,J) is at the beginning of the program. Our SegMoveTime is set to 1, I tried larger numbers but no change. If I change from CCW to CW circles (CIRCLE2 -> CIRCLE1) some circles are still skipped but not the same ones.

 

Is there a tolerance value that determines when a complete circle is executed and when a small arc is executed? Our start point and end point are identical to 5 digits so I don't see how this could be an issue.

 

As a temporary work around, I broke the CIRCLE into two 180° pieces. This works for now, but I can't tell our customers that they can't program full circles.

[curtwilson]

"Is there a tolerance value that determines when a complete circle is executed and when a small arc is executed? "

 

Yes!

 

Saved setup element Coord[x].MinArcLen -- scaled in radians -- is provided for just this reason. (In Turbo PMACs, this is Isx97.) You will want to increase this value from its default.

 

You will need to consider what the shortest arc length you think anyone will want to program in your system. If you set it too big, there will be complaints that the machine did a "loop-the-loop".

[ScottB]

Thanks, that fixed it!