Adding dimensions on curved surfaces

[vtmike]

Hi,

My part is a hollow tube with a laser cut through the thickness (shown in fig. 1). The method used for making the cut is as follows (Solidworks 2008):
1. Draw the sketch on the top plane.
2. Use split line to project the sketch on the tube inner dia surface.
3. Use surface knit to create a surface on the tube inner dia surface.
4. Use cut thicken to complete the cut through the tube thickness.
This method is used because the cut is not a straight cut, but an inclined cut sloping outwards from tube ID to tube OD. (the completed part is shown in fig. 1)

Now when this part is used to create a new drawing, solidworks cannot pick up the arcs shown in fig. 2 to dimension them. I cannot even measure them to add an annotation. I know that since they are on the surface, solidworks cannot cannot add dimensions to them, but is there any way around this? Is there any way I can use to show the arc dimensions?

Thanks,
Mike

 

[pierdesign]

thickening surface does not produce predictable parallel / perpendicular edges to direction of feature. In this it does not represent how a laser or other cutter would actually produce a normal through cut.

Try creating your cut as a separate solid body then removing the intersection bodies, forget Solidworks nomenclature, combine, or something like that. Or extrude a surface and cut with that surface, not thicken.

Probably, with true arcs created from the cut, you may be able to dimension them in your drawing.

 

[vtmike]

In this case the laser is stationary while the part is moving...an extrude cut would work if the laser was moving while the part was stationary. So it does represent the actual cut. I guess adding an annotation would be the best thing to do here.