Another polygon scanning post

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Another polygon scanning post

    I know this has been covered pretty extensively on here, but for some reason I can't seem to get this to work on my machine. I'm pretty new to CMM programming in general, so hopefully someone can kind of break this down to a level I can understand. I'm using PC-Dmis 2019 R1 with a HP-S-X1H scanning head. I'm trying to scan a polygon and then report the profile of that scan. I've been able to get the scan to work using a linear open scan but any time I try to pull up the profile it measures 0.0000 no matter what I set for the parameters. I've tried using the scan to construct a feature set and then pull up the profile of the feature set as well, and get the same result. Below is the profile I'm trying to measure. Any help is appreciated.

    Polygon.JPG

  • #2
    If you don't have cad, you have to calculate the theo values.
    Using a linear open scan as a unknown scan just read the actual profile, and compare values to itself, so it gives zero.

    Comment


    • #3
      I do have CAD.

      Comment


      • #4
        Post a picture of the 1st prompt for your scan settings.

        NULL FILTER?
        CAD COMP ON?
        PROBE COMP ON?
        DEFINED?
        CAD TOLERANCE?
        SELECT CAD SURFACES?
        CAD VECTORS CORRECT?
        # OF POINTS PER MM?
        PATH DEFINITION?
        VECTORS?
        GENERATE?

        There's a lot more to a scan than trying to break down the tiny bit of information you provided.
        Jesse Krook

        Comment


        • #5
          I scan polygons like this as well. Linear open scan, select CAD, pick points, level if necessary, RELEARN, FIND NOMINALS, CAD COMP ON, PROBE COMP ON, Set parameters (# of points etc) generate path!
          Maybe you are using MASTER or NOMINALS?? Second run would give you comparable data, first set used as nominals.
          sigpicTAU ALPHA PI INDIANA DELTA CHAPTER
          "Due to the highly confidential nature of my job, I am not allowed to know what I am doing" - author unknown

          Comment


          • #6
            I AM using MASTER. After finding/reading the Nominals Method Area in the help, I should definitely be using FINDNOMS instead. I'm not sure what you mean by select CAD. Here is a pic of my scan settings. When using FINDNOMS, what should the tolerance be set to?

            Polygon2.JPG
            Attached Files
            Last edited by jlgadrow; 10-15-2020, 07:22 AM.

            Comment


            • #7
              Settings should be:

              scan.jpg

              Make sure to select the graphics or surface(s) that you're going to scan when in the GRAPHICS tab
              Last edited by YGOLORTEM; 10-15-2020, 09:39 AM.
              Jesse Krook

              Comment


              • #8
                Alright! Now I can pull up the profile of the scan itself. Thank you so much for your help. My new issue is: when I pull up the profile, it is measuring within tolerance, but is showing out of tolerance for some reason??

                Polygon3.JPG

                Any ideas for what could be causing this? I pulled up the X,Y location of the scan and it seems like it is giving me some odd nominals. I would expect them to be 0,0 as this polygon is theoretically located in the center of the part, but when I pull up the location it is showing -.0003,-.0007 for the nominals.

                Just a quick question about the scan settings: Why .250 as a tolerance for the Nominals Method? Just curious as it seems high.

                Not sure I understand how the Graphics tab works... Under that tab I only have a "CAD Controls" section with check boxes for Select and Depth. I've noticed that if I check Select and click off to a different tab (Path Definition for instance) and then immediately click back to the Graphics tab, it unchecks the box automatically...

                Again, thank you for your help. It's nice knowing there are so many resources to gain insight when I can't figure this out on my own.

                Comment


                • #9
                  The profile callout is bilateral and you have it set to a unilateral +4 in your dimension. Notice your min value is -0.0002 which is why it is showing OOT. Change your +Tol and -Tol values to 2 each. Unfortunately it will still be OOT since your max is .0025.

                  Comment


                  • #10
                    Originally posted by jlgadrow View Post
                    Just a quick question about the scan settings: Why .250 as a tolerance for the Nominals Method? Just curious as it seems high.

                    Not sure I understand how the Graphics tab works... Under that tab I only have a "CAD Controls" section with check boxes for Select and Depth. I've noticed that if I check Select and click off to a different tab (Path Definition for instance) and then immediately click back to the Graphics tab, it unchecks the box automatically...

                    .
                    Bump since these questions weren't answered and I don't know them!

                    Comment

                    Related Topics

                    Collapse

                    Working...
                    X