Slot as Primary datum

[dwade]

V3.7MR3 CAD++

I've got a part where a round ended slot (depth is about 10mm) is the prmary datum. I'd like some input as to the best method of creating this.

I'd thought of measuring 2 cylinders then constructing a 3D line from each then a mid line but am questioning whether the mid line will be 2D or 3D.

Need your thoughts and ideas.

TIA,
Duane

[Matthew D. Hoedeman]

I think I would measure 2 slots, one at the top and one at the bottom, then construct a 3-D line through them, that would give you something to level to.