some problem with part and iterative alignment

[Vladimir]

Hello all
I have a part and I have a problem with the coordinate system, maybe I'm doing something wrong, so I will describe everything that I do in order (I use auto features and after pointing to the CAD model take them manually (measure now toggle - ON)
1. I take 3 single points on the plane ( pnt1, pnt2, pnt3)
2. take center circle (cir1)
3. take circle on x + (cir2)
4. iterative alignment
5. pnt1, pnt2, pnt3 - ZAXIS
cir 1, cir 2 - XAXIS
Cir 1 - YAXIS
6. Measure ALL iter align features
7. And now the alignment is shifting a little, and when the CMM is already taking the cir2, it simply doesn’t get into it
What could be my problem?
1.jpg

[Schlag]

Step #3. Circle on X+, cir 2. Do you mean that its the right side circle in cartesion X+ ? You didn't label it. That would be Cir 1 / cir 2 Y 0.00 and CIR B Your X axis. Label your features.No one can guess. YOu are talking CIR 1 and CIR 2 but you only show CIR B.

[Vladimir]

Sorry, you right cir1 - it's CIR B, cir2 in rigth side
Ohhh, right cir1, cir2 - YAXIS, cir1 - XAXIS
Thanks !

[Matthew D. Hoedeman]

you MUST use 3 surface sample hits when measuring a circle for an iterative alignment.

[Vladimir]

Right! Everything works ! Sample hits !

[DAN_M]

Use sample hits (required) for this work.

If your part is different from the model to an annoying degree...OR...if the geometry varies from part to part to an annoying degree where you're crashing where you shouldn't be.....you might also want to try the "find hole" option.

[Vladimir]

Ok thanks i'll keep that in mind
But once I tried to use find a hole and after that, the box "contact find hole propirtes" became inactive and you can change its parameters only in the code in edit window :/

[Vladimir]

Schlag and Matthew D. Hoedeman you helped a lot, thank you very much !
Nobody plans to teach us yet, and we have to figure it out ourselves thanks to this forum

[Schlag]

Explain to management how much money they saved by not training you when you have a machine down and your fighting over dimensional issues that are CMM related or when you get a nice reject based on faulty inspection.

[Mike Ruff]

Is your issue resolved?

don't use iterative, but I will occasionally have problems with zeroing on AutoCircles in manual alignments. When I switch to DCC, it will crash when trying to pick up the hole because it is somehow shifted by ~.1 - .2" off-center in an arbitrary direction. The fix for this is to use Measured Circles instead of AutoCircles for the manual alignment. I have absolutely no idea what causes this, but it will only cause problems with the manual alignment. I still use AutoCircles in my DCC alignments without any issues.