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ISDX Surface Changes When The Accuracy Changes


New member
I have and isdx feature (curves and surfaces) that changes severely when I modify the accuracy of the part. None of the other features change.

Does anyone know why this happens, and/or how to fix it?




New member
Why you do that is first question!

Can you work without that changing?

Can you think and implement some workaround?

I don


Can you add a before and after picture. I can not be sure but a good guess would be the accuracy affecting the first and second derivitives particularly at a local maxima or minima or point of inflexion. ie. the old accuracy picked points on either side of a max and the new accuracy happens to land on a max.

Just a guess.


New member
Attached are 2 jpgs that show the surface before (isdx-1) and after (isdx-2) I enter a lower number for the accuracy. I started out at .0008 relative and changed to .0003 absolute.

My current fix:

I went back into the model and added a datum point to align the corner moves curve juncture. Both the curves and surfaces were created in the same isdx feature.

View attachment 337

View attachment 338




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