Second Alignment Issues_Need Help

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  • Second Alignment Issues_Need Help

    I am having issues creating a second alignment to report the locations of the bolt holes around Datum A. Datum A is 6.25 degrees from my original level feature which is Datum's B and C. I would love to just translate my alignment to datum A, but since it is over 6 degrees I would have to level to it to have an accurate report on the bolt hole locations. When I do level to it, it then throws my previous features like datum's b and c off y model because of the new level feature. Am i missing something here? Or is this possible to work around? Any help would be much appreciated. I have been looking through these forums to find the answer, but to no luck.
    Attached Files

  • #2
    Are you inserting the results/measurements above the features you are having problems with, when t
    you create the new alignment are you being prompted to update the nominals


    • #3
      If you use FCF, and unselect something like "use alignment", it should work directly ?
      I'm not at the cmm to use the right sentence...


      • #4
        No I am not being prompted to update nominals. I created my first alignment then measured datum A, then tried to create the second one. I have not measured any other features other than what I needed to do my alignments. I had written a program for this part last week and realized afterwards that switching between the 2 alignments was moving my programmed and measured features off my model, you can hardly see the change that happens while going from one alignment to the other. Now I am going back to it in a new program to try to work around it so I have not created any other features or dimension.


        • #5
          Your GD&T says -D- then -B- THRU -C-. That is how the position needs to be calculated. However, as you know, being aligned to datums that aren't square to your measured feature makes it hard/impossible to interpret the cmm's results. So, you'll set up your base alignment then offset it to get your compound alignment.

          You didn't show us what -D- is...regardless...recall startup..level to -D-, rotate to a line made from -B- to -C- (measure -B- and then -C-, put a point at the center of each, construct a 3D line), then set -D- as one origin and Axis B-C as the other two. That is your base alignment. Now you'll need to rotate THAT your 6° (or whatever basic is) to get yourself square. Now that you're square, report your hole within the compound alignment.

          The hole itself should have some basics that control it's location that reference back to your alignment.
          Last edited by DAN_M; 03-12-2020, 02:36 PM.


          • #6
            Option 1: It seems like you first need to check the 'Warnings' tab in your F5 settings. You may be answering 'Yes/No' automatically after updating your alignment causing the graphical issue.
            Option 2: Is your recall alignment correct?

            Option 3:
            If you level A, then measure B and C, PC-DMIS should be able to calculate/update your vectors.

            If you have a rotational stop that is consistent with your angular offset of the primary datum perform your clocking arrangement to get the part situated, then go back and measure A and tilt it against the proper axis to go back and measure B and C to complete your final alignment:
            A level
            A origin
            Rotate about axis by required amount
            Rotate tertiary about secondary
            X origin
            Y origin

            You now have your 6 degrees and have respected the [BSC] while keeping your measurement code closer to 0's and 1's for easier understanding.


            • #7
              If you go back to the first picture I attached it shows that D is the plane that B comes off of. So there for B and D both have the same vector direction and I can not level and rotate in the same vector. So what I did was level to a D Best fit line that went from B to C then rotate to a line made from 2 of the circles shown in the bottom right corner of the second picture. In my mind since I was not able to do alignment as the print calls I figured leveling to B and C was better then D to keep everything coming off the center line of the part. This is the best way I can figure out to do this with D and B being the same direction. I will add that I am not trying to report on the position of A, but rather the location of the 3 holes that are around A. I apologize if this seems pretty basic, I am only a few months in to all this world. Also am on an Arm and not CMM.


              In the setting dialog I do not my warnings turned off, was able to verify this by changing a letter ina name of an alignment feature. It asked me if I wanted to update and that something was wrong because of the name change.


              • #8
                You need to rotate to something else. Level to B-C. this will be Y and Z origin ( or whatever based on how you part is sitting ) D will be X orgin. USe the width or edge of E ??? The bottom portion of the postional call out doesn't make any sense. You have more issues than 1 on this part.


                • #9
                  I think you are trying to report the dimensions referenced in the center view of right print? Does the drawing have positional location callout for that 3 hole pattern around A? Based off the center view of the 2nd print, measure cylinder A, the face of the A bore and E. Level Z+ to A, rotate Yplus to E, origin Z to bore face, origin X to A, and origin Y to E with the 1.313 basic offset.
                  153010 Global Advantage w/ LSPX1H_T Analog Probe
                  7107 Global Classic TP20
                  2019R1 SP1 CAD++


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