Material Thickness Compensation

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

  • Material Thickness Compensation

    hello I am new to the forum. how could I add material thickness compensation for example I have a part that gets nickel plated and we measure it before it gets plated but our results seems to be a little of and we believe is because the cad includes that nickel thickness. Is there a way to add this material thickness. I previously used Mcosmos and they have an option for material thickness compensation but I cannot find it on pcdmis. Can anyone help. thanks alot

  • #2
    https://www.pcdmisforum.com/forum/pc...s-stock-to-cad

    https://www.pcdmisforum.com/forum/pc...ial-thickeness
    "This is my word... and as such is beyond contestation."

    Comment


    • cowrevenge
      cowrevenge commented
      Editing a comment
      This is the only answer you need. It even calculates the position changes on angles.

  • #3
    Hi and welcome to the forum. Not sure what exactly you are looking for but most parts get plated as a final finish. The easiest way to compensate is to change your report nominal to reflect the amount of plating you are expecting. This is you pre-plate dimension. If you check the parts after finish then the actual print/cad nominal would apply. For instance: you have a dimension at .035 but you are expecting to add .001 plating to the product, then you change your nominal to .034 for the machining op. Cad models are usually designed to reflect final dimensions for a part . That is how I have always done this. Hope this helps you.

    Comment


    • UKCMM
      UKCMM commented
      Editing a comment
      The guy is talking about compensating for plating thickness not a CAD model error/problem so not sure why you think this. If the model is at final size post plate and I expect it is as I have never seen an engineer model to allow for plating then you can either change the nominal and dimension tolerances or just change the tolerance to accommodate the plating allowance, not sure why you think this is a problem.
      Why do you think doing this on a sphere is going to be an issue the approach hit vectors are the same just the diameter has changed
      Last edited by UKCMM; 06-15-2018, 05:14 PM.

    • cowrevenge
      cowrevenge commented
      Editing a comment
      "I previously used Mcosmos and they have an option for material thickness compensation but I cannot find it on pcdmis. Can anyone help. thanks alot" - OP

      Not sure where the confusion is. He is even using the terminology of material thickness. Its clear neither of us are interested in changing viewpoints. I have no qualms with the output of your method, only that its incredibly inefficient. Many programs will allow you to use an offset on the cad model as a whole. This is not transforming, as it it accounts for vectors. Polyjerks for example, import cad, edit offset, done. No need to do it for ever feature like PC-DMIS.

      Please try and change my mind, I am happy to listen. I just do not understand why you want to edit the nominal manually over and over. What happens if t the plating changes thickness? Polyworks, i change the cad offset and I'm done. PC-DMIS, I change the offset of each feature to the new plating thickness.

      Your way, I open every feature and manually calculate where the nominal is now. Then I enter the new nominal. That is 2 potentially long steps instead of one quick step. It would be next to impossible for a trainee to do it your way. You could train a new guy to use offsets and Theo/Act from day 1 without the need to explain it a hundred times. It simply works.

    • VinniUSMC
      VinniUSMC commented
      Editing a comment
      Cow, the OP is talking about plating thickness. You're talking about material thickness. It's ok, but tangential to the needs of the OP.

      UK would be correct that it is standard operating procedure for CAD to be modeled to the final product (that is the default), but the OP should verify that with the customer, not with us. I don't think that anyone should be adjusting for pre-plating as a) plating thickness is variable, and b) that's not the salable product. But, in PC-DMIS you would do that with the Thickness option.

  • #4
    I like the answers above; they pretty much all say the same thing.

    Quite frankly I am not checking the OD of our round parts, simply because we have a better gage for it (tallyrond), but if I were I'd just adjust the numbers.

    I work at a machine shop, so the below may not apply.

    If it's a Blank part, the OD will match that of the stock blanking used to cut out the general shape of the part.
    If it's a Secondary part, the OD will be a bit larger than the nominal after plate size on the print.
    If it's a Plating part, the OD will be the nominal After Plate size on the print.

    Comment


    • #5
      Originally posted by alex.monteagudo View Post
      hello i am new to the forum. How could i add material thickness compensation for example i have a part that gets nickel plated and we measure it before it gets plated but our results seems to be a little of and we believe is because the cad includes that nickel thickness. Is there a way to add this material thickness. I previously used mcosmos and they have an option for material thickness compensation but i cannot find it on pcdmis. Can anyone help. Thanks alot
      i found your problem. How bout you contact the customer and find out the answer instead of guessing.
      Nowadays the CAD is used as the Master. Measure the part to the CAD. If there's any doubt, call the customer and verify if the CAD is PRE or POST plating. CYA.
      Last edited by BIGWIG7; 06-15-2018, 02:15 PM.
      Che Guevara is a communist scumbag.

      Comment


      • InspectorJester
        InspectorJester commented
        Editing a comment
        +1000 on this point, especially if it's a CAD drawing straight from the customer or engineer.
        They can make a CAD model; it's part of your job to make sure it's correct, or that at least you understand why it was made this way or that.

        EDIT:
        Our QM is constantly bumbling around attempting to make decisions for our customers instead of just sending an email or something to make sure everything is correct on everyone's end. A simple series of communication would solve almost every problem

      • cowrevenge
        cowrevenge commented
        Editing a comment
        Quality is family, we do not communicate.

    • #6
      I already check with the customer and the CAD is post plating.

      Comment


      • #7
        Originally posted by Alex.Monteagudo View Post
        I already check with the customer and the CAD is post plating.
        If your cad model includes the plating:

        1) Use an COMMENT_INPUT at the beginning of the program, 1=plated, 2=un-plated
        2) Assign a variable based upon the input, for plated the variable will be 0 (zero) and for unplated the variable will be -(plating thickness) (NEGATIVE value of the plating thickness)
        3) Use ACTL_THICKNESS for all features, and use that variable for the thickness value.

        This gives you 1 program that can check either plated or unplated and give the correct results.
        sigpic
        Originally posted by AndersI
        I've got one from September 2006 (bug ticket) which has finally been fixed in 2013.

        Comment


        • VinniUSMC
          VinniUSMC commented
          Editing a comment
          Except for plating thickness being variable.
      Working...
      X