Hole diameters

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

  • Hole diameters

    This may sound dumb, but I'm trying to explain to my manager, whom has no experience with CMM's, how a diameter is created. He seems to think, that when 4 or 5 points are taken on any given hole, somehow 4 or 5 diameters are taken and the average is used to create the hole. He seems to think I can just click on something to see each individual diameter that's used for the average. With only 4 points, I don't see how he thinks there's 4 diameters being taken. What's the easiest way I can explain this to him?

    Thanks in advance.

  • #2
    Don't. Sounds like a waste of time. Explain to him that there's only one diameter unless you measure as a cylinder then you can individually see the diameter at each level.
    Darroll
    2018R2

    Comment


    • #3
      Tell him it calculates based off the fitting algorithm for that feature. MAX INSCRIBED, LEAST SQUARED, MIN CIRCUMSCRIBED, etc. That should satisfy him, and if he doesn't understand that, then he shouldn't be asking those types of questions lol

      Comment


      • #4
        Kinda yeah, Technically what DMIS does is taking the value of each hit from center and averages those hits to create a size, if you try to stick a gage pin based off of that size, it won't go. If you report MAX and MIN, basically a GO and a NO-GO pin. When you look at your result of your MIN. This would be what gage pin that will go, I myself would take more hits to tell me if there is anything wrong, what if you have a drag mark from the tool, that the probe is touching, giving a bad reading or maybe it's not touching leaving you unaware of anything wrong. My biggest argument is a circle to represent a cylinder? Well that's just stupid. That is a manager trying to get you to cut corners and get the product out the door because, he or she has their head so far up the bosses "___" that if the boss made a sudden stop, they would both die.
        (In Memory of my Loving wife, "Ronda" who I lost March 7, 2016. I love you baby.)
        They say "Nobody's Perfect." I must be Nobody.

        Comment


        • #5
          Try to explain with this kind of picture (squared hole ) (even if it would be stupid to measure it as a circle, but don't say it to him !)
          4 hits aren't enough !!!!!!

          square holes.JPG

          Comment


          • dph51
            dph51 commented
            Editing a comment
            It’s a SQUARCLE

        • #6
          Originally posted by KIRBSTER269 View Post
          Kinda yeah, Technically what DMIS does is taking the value of each hit from center and averages those hits to create a size, if you try to stick a gage pin based off of that size, it won't go. If you report MAX and MIN, basically a GO and a NO-GO pin. When you look at your result of your MIN. This would be what gage pin that will go, I myself would take more hits to tell me if there is anything wrong, what if you have a drag mark from the tool, that the probe is touching, giving a bad reading or maybe it's not touching leaving you unaware of anything wrong. My biggest argument is a circle to represent a cylinder? Well that's just stupid. That is a manager trying to get you to cut corners and get the product out the door because, he or she has their head so far up the bosses "___" that if the boss made a sudden stop, they would both die.
          Is there a way to dimension each point taken? Thanks.

          Comment


          • #7
            Take the hits manually, and construct a diameter. Origin to the diameter then dimension the individual hits as polar radius points.

            Comment


            • #8
              yeah, probably going to, too much trouble in my opinion. Individual hits, what kind of holes are you dealing with? I would suggest on small holes no less than 5 hits, and as it gets bigger add more points. How deep is the hole? Does it have position callout? This is just an estimate, some may beg to differ, if the depth of a hole is 7/16 or more I start to treat it like a cylinder, also depending on the material that may vary. T-Value or Polar Radius. Can't really answer the question if I don't know what I'm dealing with. Are you making parts for IKEA? H_ell 3 hits for a circle is sufficient for that crap.
              (In Memory of my Loving wife, "Ronda" who I lost March 7, 2016. I love you baby.)
              They say "Nobody's Perfect." I must be Nobody.

              Comment


              • #9
                Remember when you create a feature (Mating Part) That's what you create to mate into the part. A circle from top view and side view. That is your presentation of your Gage Pin. Mine of course is the bottom which represents my Gage Pin. I believe, this will help the machinist make better quality parts, not quantity parts.

                Untitled.jpg
                (In Memory of my Loving wife, "Ronda" who I lost March 7, 2016. I love you baby.)
                They say "Nobody's Perfect." I must be Nobody.

                Comment


                • #10
                  Originally posted by KIRBSTER269 View Post
                  yeah, probably going to, too much trouble in my opinion. Individual hits, what kind of holes are you dealing with? I would suggest on small holes no less than 5 hits, and as it gets bigger add more points. How deep is the hole? Does it have position callout? This is just an estimate, some may beg to differ, if the depth of a hole is 7/16 or more I start to treat it like a cylinder, also depending on the material that may vary. T-Value or Polar Radius. Can't really answer the question if I don't know what I'm dealing with. Are you making parts for IKEA? H_ell 3 hits for a circle is sufficient for that crap.
                  7.2 mm holes

                  Comment


                  • KIRBSTER269
                    KIRBSTER269 commented
                    Editing a comment
                    we all already answered that, how deep?

                • #11
                  Originally posted by MatttFlorer View Post

                  Is there a way to dimension each point taken? Thanks.
                  Yes, if you are conversant with the power Command Mode as opposed to the weakness of Summary Mode.

                  For convenience, let's name the circle CIR1

                  After the circle, make a temporary alignment that sets Origins on the circle.

                  Next: Construct Point, choose Cast, choose the circle, Create, close dialog.
                  Then manually edit the name of the feature being used from CIR1 to CIR.HIT[1] to make the point out of just one hit.

                  Repeat for every hit.

                  Open up the Location dialog and dimension the PR of each point - this is the Polar Radius, the point's 2D straightline distance from origin in the current coordinate system which you made centered on the circle.
                  FYI "PA" right next to it is Polar Angle, see if you can figure out what that is for your own education.

                  Finally, make a Report Comment before the dimensions explaining to the readers that these extra useless PR dimensions are for your clueless boss.

                  Good luck!

                  Comment


                  • #12
                    Originally posted by MatttFlorer View Post
                    This may sound dumb, but I'm trying to explain to my manager, whom has no experience with CMM's, how a diameter is created. He seems to think, that when 4 or 5 points are taken on any given hole, somehow 4 or 5 diameters are taken and the average is used to create the hole. He seems to think I can just click on something to see each individual diameter that's used for the average. With only 4 points, I don't see how he thinks there's 4 diameters being taken. What's the easiest way I can explain this to him?

                    Thanks in advance.
                    Tell the pointy haired boss that “it’s magic” and “only super intelligent people understand it’s intricacies. Only dolts can’t see how it works”.

                    He will never bother you again.

                    B&S CHAMELEON/PCDMIS CAD++ V2011

                    There are no bugs, only "UNDOCUMENTED ENHANCEMENTS!"

                    sigpic

                    Comment


                    • #13
                      Found a pic of Mattt's boss...

                      PBH.jpg

                      Comment


                      • #14
                        The only way anyone with no experience is going to understand one iota of what the CMM is doing is to set him down, put the jogbox in his hand, and have him take hits, explaining the difference between a point (one hit), a line (at least 2 hits), a plane (at least 3 hits), and all the other geometric figures that can be created taking hits.

                        Explain that when the unit is scanning, it's taking hundreds of hits as it's moving along.

                        If he can't grasp it, he's got no business holding the position he does.

                        Comment


                        • #15
                          The First sign of a person lying about their knowledge of PC-DMIS, or pretty much anything. When their first line of defense is "I have been doing this for 20 years!!!" You know their lying because they will use increments of 5 years, 10,15,20, or 25. You'll never hear anybody say 30 or more, unless they're retired, dead, or Matthew D. Hoedeman . Anyways, they hired you to program, I assume? If He or She is telling you how to program, then just tell He or She to go ahead and make the programs and you'll just run the CMM. We will help you on this site, and do our best not to steer you wrong, but one thing you can't do is listen to an expediter, you will fail miserably. Good Luck
                          (In Memory of my Loving wife, "Ronda" who I lost March 7, 2016. I love you baby.)
                          They say "Nobody's Perfect." I must be Nobody.

                          Comment

                          Related Topics

                          Collapse

                          Working...
                          X