6 Replies Latest reply on Jan 14, 2015 6:25 PM by Jonah Champagne

    Having trouble dimensioning a drawing properly...

    Jonah Champagne

      Hi I have a question that I've been struggling with for a while now. I created a drawing from a solid model and am attempting to dimension the drawing. The drawing is of a pump base plate with a large hole towards the center of the plate and various through holes and tapped holes around the plate. I need to reference everything from the center the large hole in the plate. It seems solidworks will only make vertical and horizontal dimensions whereas I'm trying to input a distance dimension (inclined in this case). Anyone know how to do this? Also, I need to insert an angle dimension between the tapped hole centers and the center of the plate. Any help would be greatly appreciated.

        • Re: Having trouble dimensioning a drawing properly...
          Mike Pogue

          The first figure is I think what you are asking for. You can assume the angle for any feature at 90, 180, 270, so they need not be dimensioned. To get any off-angles, you'll need to draw a line from the center hole through the hole whose angle you want. There is nothing to stop me from putting down the 6.094 dimension as shown. Click both holes and drag the dimension around until it goes oblique. This first figure is a highly non-standard way to dimension a part, but I think it meets ASME. It has serious tolerance issues, though.

           

          The second figure is how most people would probably do it. You have to make sure you BC diameter is driven by the hole, and not by the dimension (i.e., make sure your dimension is driven). I would normally omit B.C. or BOLT CIRCLE, because it doesn't really add any information. But most people would add it

           

          I would personally do this with GD&T, because bolt circle dimensions usually have serious tolerance problems which are rescued by CNC machines. In that case, I'd do like Figure 3. You'll notice that datum C is clocked off itself, which is to say not clocked at all (not 100% kosher, probably, but gets the message across). If there were some clocking feature that actually mattered, I'd try to use that as a datum instead of the top hole. But, unless that feature really mattered, I'd probably be making the drawing worse by doing that. The other holes are clocked to datum C.

           

           

          • Re: Having trouble dimensioning a drawing properly...
            JOHN GEORGE

            SW 2014 introduced angular ordinate dimensions

            See this

            • Re: Having trouble dimensioning a drawing properly...
              Jonah Champagne

              Mike: Thanks for your help, your pictures show exactly what I'm trying to do! How do I add the BC callout? Also, how do you add the angle? I've tried multiple things but can't seem to make it work...

               

              Thanks,

               

              Jonah