Unwanted point changes

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Bubba1950
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Unwanted point changes

Post by Bubba1950 » Thu Jan 12, 2017 5:58 am

We are new to CMM Manager and are having multiple issues with point movements. Just about every time we open a program we find that the points we want to take are now moved to another location. After Free Positioning and setting the origin to the Free point, we either create a reference frame or do the Runtime Align Part. From there we do an Add Move to a depth. As in creating an internal midpoint, we have it take a point at say -0.500,0.0.75 - which works fine when we do it. But the next time we run the program, our add move has changed from 0,0,0.75 to something like -0.948,0.613,0.75 and our -0.500 has changed to maybe 0.634 or something. Why is this doing this?? We have been struggling with this for weeks. Sometime everything seems to be okay, other times it's a constant issue. Any help would be appreciated. Thank you.

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US_Helpdesk
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Re: Unwanted point changes

Post by US_Helpdesk » Thu Jan 12, 2017 10:45 am

This is normal for points before the Alignment to drift in location... This is just the results of the program running on your CMM in a slightly different location each time. This would be strange to see after the Alignment (Free Position does not count) Can you confirm the Alignment is determinant? i.e. complete / all 6 degrees of freedom constrained.
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cindy581
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Re: Unwanted point changes

Post by cindy581 » Wed Feb 01, 2017 10:11 am

Hey it's Cindy here & I'm having some issues with nominal coordinates, picked from CAD, changing in my "feature" window. The same nominals in my reporting window stay as originally programmed. I can open my part program, view my CAD point nominals in the feature window & one or two directions have slightly changed from my original programmed point. I've added the Run Time Alignment in my program before I "report" my CAD point. But it doesn't make a difference, it still changes. I'm attaching 3 program pics. 1st shows the beginning of my program. I do a manual alignment, sync CAD, save ref frame, recall ref frame, run time alignment, an automatic alignment then sync CAD again, save a new ref frame, recall that ref frame, run time align, then start measuring my features & reporting them. 2nd pic shows my CAD nominals that have changed, 3rd pic shows my original CAD nominals in my feature reporting window (those are correct). I've been having this issue every now & then. I believe it can be caused by "editing" a program in teach mode after a part has already ran thru the program. Please help me anyone......I'm so frustrated

Thank you,
Cindy Looks like my pics attached in an incorrect order. Sorry..
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Ryan Christopher
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Re: Unwanted point changes

Post by Ryan Christopher » Thu Feb 02, 2017 1:50 pm

Hi Cindy,

If you are newer to CMM Manager it's good to see that you are trying out some of the advanced alignment functions. In this case though, it may be that they are getting you into trouble.

In my classes, I start new users making (cad) programs with the following format. This structure remains pretty much constant no matter what my program contains.
C1.JPG
One caveat to CAD programming with CMM Manager (and some others) is that to ensure nominals don't change when you create new alignments, your nominals and actuals should be the same while you are programming. The first way to ensure that is by measuring with the orange cad measure tools and by turning off the update actuals setting so that if you use verify it won't get you into traouble.
C2.JPG
The other way is to "select all" your program and reset actuals before changing an alignment.
C3.JPG
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Ryan Tackes
Applications Manager, VMS Inc.
http://www.vantagemeasure.com/

cindy581
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Re: Unwanted point changes

Post by cindy581 » Sat Feb 04, 2017 10:05 am

Hi Ryan,
Thank you so much for your suggestions. I'll try them out on Monday. The only time I notice my cad nominal change is when we have measurements out of tolerance, unfortunately. I have noticed the only time they change is if I edit anything in my programs, which can be after I've ran a part & there is current run data in the run database. The run database & teach mode database is so frustrating for me. My last software was GeoMeasure and we didn't have issues editing or adding to a program already written. I've got 20 + years with programing on a cmm but this is my first using the cad interface. I've pretty much got a handle on it all, mostly.
We mainly write part programs that can be ran multiple times. 5 pc full layouts & 30 pc capability studies. No part fixture ref frames because the parts will only stay in that particular location for that one complete run. Couple days later, we can run new parts with the same program, but the part might be in different location on the machine (from the programming location). It just seems like the DCC alignment that is made on each part during the program, isn't the origin that my features are being reported back to. Seems like they are being reported back to the one time manual alignment/origins. I'm just not completely sure what's going on, but I gotta figure it out soon. We've had to re-run batches because of this issue.
Any more tips, please pass them on.....I'll take all that I can get. LOL

Have a good one,
Cindy :)

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Re: Unwanted point changes

Post by medupriest » Mon Feb 13, 2017 10:26 am

Hello Cindy,

The reporting is always done using the current reference frame at that point in the program. If you suspect something isn't, save some run results (saved form the program ribbon tab or auto save options in the pearl). Then zip and attach the run results and the project file.

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