Hello everyone. I am having trouble trying to dimension to the midpoint of this radius callout, rather than the center. In the drawing, shown below, there is the .244 dimension from the centerline of the 45° BSC angle to the midpoint of the radius. I have adjusted my alignment to fit the 45° BSC angle and have measured a line on the 40° surface, measured the radius as vector points and a constructed circle, and have made a cast point to the cylinder (the origin). I have tried making a pierce point from the line, to the origin (cast point), to the circle (.100 radius) but it is not exactly at nominal. Is there a way to properly inspect this dimension?
Kinda hard to see, but it looks like the 0.244 dim is to the tangent point of the radius and the 40° surface. Is your line direction on that surface pointing towards the radius? if yes, then pierce point from line to constructed circle. If not, then construct a line in the opposite direction.
The callout is not to the tangency point but to the midpoint of the arc of the radius. I can't dimension to the centerpoint of the measured circle because it would be off. I was debating just making a vector point from the theoretical X & Y locations (found from the Solidworks CAD file) but I am not sure if that is the best way to go about it. It seems like there would be a lot of room for error that way.
It looks like the dimension is to the intersection point of the 40° angled cut and the OD of the part. i.e. if the .100 radius wasn't there and the corner was sharp, it would be to that point. Try intersecting the 40° line with the OD of the part (just make sure your line is pointed the right direction or it will intersect the other side of the circle).
Hi Mike! Thank you for the reply. Unfortunately it is not that easy, as the dimension is to the midpoint of the arc of the radius. I know that in a Solidworks CAD file you are able to select the midpoint and dimension it accordingly, but I am not sure how to measure this in PCDMIS.
If I am understanding correctly then this my help.
Measure the line at 40 degree.
Measure the small radius R0.100
Measure the large outside diameter.
Construct the point between the line and small rad I will call it point 'A' for example.
Construct a line between the small radius and the large diameter.
Construct a point between the constructed line and the large diameter I will call it 'B'
Construct a line from the point 'A' and the radius
Construct a line from the point 'B' and the radius
Construct a mid line between the two new lines
Construct a point between the mid line and the radius.
I know it's not a full 90°. Depending on the length of the arc, DMIS could have a hard time calculating the data accurately, correctly, and repeatable.
Hello and thank you for the help! I was able to push back on our customer to change the callout to the wall, not the midpoint of the radius. Makes everything a lot easier! Have a great day!
