XY basics for a true position do not match the XY as a location.

[bbennett]

I am working on a pretty simple part, but when i ran my first test on a machined part i have 2 true positions that i cant quite figure out.
The features i am checking are 3 1/4-20 threaded holes.
The information i am reporting seems physically impossible. According to the position the hole location has a deviation of 0.7 inches and 0.9 inches. The first hole measured looks correct, the 2 others not so good.
The part is being aligned using the datums that are called out in the true position.
I am even more confused after double checking the location and using the other TP format. The nominals in the location and the first position are correct to the CAD.

[JEFMAN]

Could you also post the cde, with datums def and alignments, please ?

[Schlag]

Create new dimensions and re-run the part. The naming convention you used for the dimension may be the problem, Why would you have / in the dimension name ?? That's prolly a no-no....

[bbennett]

JEFMAN Attached is the code for the alignment, datum def, and the holes that are the issue. The first hole measures and reports fine, but the other 2 measure fine but do not report correctly.

[JEFMAN]

Thx, I saw that the problem is fixed...
In the prog, I don't see how you construct datums...
But no matter while it's fixed

[bbennett]

The naming convention you used for the dimension may be the problem, Why would you have / in the dimension name ?? That's prolly a no-no....

That was how i was taught to list the balloon print numbers. I have done it that way for 9 years and it was done that way by my boss since we switched from measuremax. I have never had an issue with it, but will try.

[bbennett]

So i created the new dimension and it looks good on paper, going to rerun the part now. UPDATE All good now. Deleted the position and created new ones.

This is a program that i made for an almost identical part. They are 95% the same castings and machining. This bolt pattern was programmed to the other part. The one big difference is that the pattern is rotated 180°. After the original program was proofed out and complete it was modified to the 2nd part.

While writing this i thought to check the original program, and for some reason the position did not update correctly with the new coordinates.

Thank you for the suggestions and being my sounding board. I am the only one at my shop that knows PC-DMIS so this forum is my only real place to work through any issues i can't figure out.

[Schlag]

For feature names and dimensions. LETTERS NUMBERS and _ No exceptions

[mbatten]

Yes, sometimes the XactMeasure True Position either gets bad nominals somehow or retains old ones for no apparent reason. Sometimes opening the edit window for it and then clicking OK will fix it, sometimes you need to re-create the dimension from scratch to get it to work.