Dimensioning Problem

thomas_miglinci

Hello,

I encountered the following problem with a drawing: (see https://cad.onshape.com/documents/c4a43830ba766cc6ce0d27ed/w/09b56e4c8a752a62e2941390/e/fd9aab1d02deb8471bb68c57)
I have to pairs of holes which are on different sides of an object (in this case an L-profile) but are arranged symmetric to a common centerline. This is easy to construct in a Part Studio as these centerlines can be aligned on the corner and the distance for this line can be set from the baseline.

But when I want to make a drawing out of it:

• I cannot direct draw a centerline between the holes. This can be faked by drawing two separate lines horizontal from both holes and attaching a centerline between those lines. And, this lines will not move if the underlying view is moved :-(

• The distance of this faked centerline to the base of the object cannot be dimensioned at all !

Any help is appreciated - thanks
Thomas

NeilCooke

Hi Thomas, you are correct, this is not possible. You probably don't want to hear this, but you cannot physically measure an imaginary/inferred symmetry line, so best practice is to dimension all features from a hard edge.

thomas_miglinci

Hi Neil,
yes, I do not like the answer, although I do understand your explanation.
Thanks
Thomas

owen_sparks

Morning Gents.

I've not tried such things in drawings but in assemblies you can use dummy parts set to 100% transparency (or just hidden) to act as helper parts for locations / mate points etc.  Could you do something similar here?  If so that might retain the parametric nature of the dimensions.

Owen S.