Caliper Distance

[[An...]]

Hi everyone!

I'm trying to match the measurements from a supplier.  I'd been unsuccessful so far - they were nice enough to send me their CMM reports.  It seems like it should be easy - but we are getting different values.  (Not just normal measuring in different spots).  I'm trying to measure plane to plane distance.  They are offset from one another.  I thought I could do a cartesian distance - and verify the parallelism.  

The supplier is using caliper distance.  I... haven't used this before.  I went back and checked my basic Calypso training - and apparently I took notes on everything else.

I'm a little unclear as to what I should be using, if it is caliper distance - how does one best choose the variables?  

Thank you all for your help!

 

[[Ma...]]

Caliper distance is dependant on alignment, but you have an ability to select what result you want ( for planes: min/max/mid | for circles: center/min/max )

I am using that rather than cartesian distance. Cartesian distant is making perpendicular distance from second element to midpoint of 1st element. So you can get two different results.

What to use is depending on tolerances, usage of the part and drawing - or if you are hunting numbers, then you have to check all to find what they did. I assume that they were wrong at some point 😄 

[[DW...]]

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 Cartesian distance is a center to center (centroid?) distance normal to the axes. Caliper distance lets you chose between min, max, center for each feature and output distances like X,Y,Z, 3d (simple distance) or even radial distance (all with or without additional alignments). Perhaps they are measuring max to max or min to min to get good numbers? Check using caliper distance on your own machine after measuring both features and/or use one of the planes as a datum to see what parallelism looks like with respect to the other plane. 

Edited October 27