Measuring on non-planer surfaces


I have a non planar surface -- in this case a portion of a large cylinder. I need to measure how far apart holes are on the outer surface -- so they can be drilled when the cylinder is flat.

Any bright ideas ??


-- Regards, Gavin Melville

Reply to
Gavin Melville
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presumably you know the radius-use the axis of the cylinder to measure angle between features and an edge and work out the ratio to the circumference-i.e. 36deg= 1/10 2piR- use the measure tool for offset parallel to the axis

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Model the cylinder as sheet metal, and flatten it



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You could also look at it from the end (normal to the plane generated by the

2 holes) and create a sketch that consists of an arc on the surface. This would start and end at the axis of each of the holes. Then put a ref dimension on the arc length.


Reply to
Wayne Tiffany

Gavin, In the model, create a sketch on a planar surface that shows the holes in profile or select a plane that is representative of this view. Use the edge (convert) of the outside cylinder, place two construction lines at the hole centers, trim the arc and then input an arc dimension. This is done by selecting both arc end points and then the arc itself. The selections can be made in any order. Eddie

Reply to
Eddie Cyganik

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