When trailing out NX CMM I noticed that there is are alot of PMI in modeling mode that is not usable down stream into NX CMM. The sad part is that when appling it within modeling mode there was no way of know what would be applicable or not. I realize there is a list in the documentaion but I wish there was a subset of PMI options that labled for CMM as the workflow will most likely be engineers applying the dims and then a programmer trying to inherit them latter.
Anyone have decent workarounds for ensuring they are applying the correct PMI for downstream use?
I would also be interested in any findings on this subject. I'm also interested in the impact of creation method on downstream usability. What happens when the CMM expects a face reference, but the Designer author selected an edge? Can the PMI throughput be improved by authoring PMI more carefully?
Although we are just starting with PMI implementation, we have run test parts through the latest versions of Calypso (Zeiss) and PC-DIMIS (Hexagon). In both cases, the following was found to be true:
1- All dimensions MUST be associcated with FACES. If the dimension was created using edges, the dimension must be edited to add faces.
2- All GD&T MUST be created using the GD&T menus, and associated with FACES. If the GD&T is added as text to the dimensions, it is ignored by the CMM program.
3- In general, our testing showed that the PMI was used by the CMM software, IF it was created by the proper menu selection (e.g. Datums by Datum menu, GD&T by GD&T menu, etc.) & is associated with faces.
As noted before, this data is based on a limited amount of testing, and may, or may not, solve your problems. However, I do belive it is a good start on creating "best practices".
Thanks for sharing that information ASML_DROF. Our own limited results indicate the same.
Although I do not use Model Views, it seems most are. I'm wondering how it is to apply PMI to faces that are represented edge-on in a Model View. I played with it myself and did not find an obvious way to make NX select the edge-on face during PMI creation. Setting Selection Filter = Face, would only select non-edge-on faces (IE. not that face I wanted). Quick Pick does not appear during PMI creation placement. Is everybody who wants CMM appropriate Associated Objects rotating the Model View so as to be able to select the appropriate face? Or, am I missing something obvious?