I found conversation about minimum distance between two surfaces.
Is there in Rhino some command to find maximum perpendicular distance between two surfaces?
It would be nice to know the location also.
Green curve in attachment file is just guess/example where it might be.
Thanks: Henrimaximum distance.3dm (100.4 KB)
Hi Henri - I dredged up an old script that I made for this - you can give it a try - it marks the max deviation location. Note the script uses the surface anlaysis meshes, so it helps a lot, in terms of accuracy, to run a surface anlaysis command like CurvatureAnalysis on the surfaces first and set the analysis mesh (Adjust Mesh button in the control) to be very fine/accurate. The easy way to do this is to set the āMaximum initial grid quadsā in the detailed controls to something large, like 5 000 - 10 000. Close that then run this toolā¦
SurfaceDeviation (3).zip (3.7 KB)
To install, unzip the rvb file from the archive to some place that makes sense to store it, and then drag and drop the rvb onto an open Rhino. This will add the alias
SrfDeviation
which can be used like a normal Rhino command.
Note the script uses analysis meshes to do its thing, so youāll want to run something like CurvatureAnlaysis once in your file and adjust the mesh to be pretty fine - that will establish the analysis mesh settings for the currrent file and the script will have more to work with.
-Pascal
Thank you Pascal!
Sounds great, Iāll try it next week!
Henri
Works great, exactly what I needed 
Thanks Pascal!
OK, good deal!
-Pascal
How do I bake this onto something so it remains static? Iād like to have a more permanent version of the graphical analysis.
Hello- see if ExtractAnalysisMesh does anything good.
-Pascal
Iāll definitely try that out. Seems like Iād forgotten about that tool.
Iām having trouble atm with the mesh that wont process on, and wonāt split more than one way. hof.
i canāt get this thing to work ā¦ fml 
PointDeviation command will give you the distance, but it will not give you exact location - only a bunch of colorful lines. It takes about one minute to find the longest line.
What I need is a āgradientā style extracted analysis mesh that indicates ādeviation from original shapeā.
I have a die that I built 14 years ago, and I reverse engineered it last year, kinda for fun, but now Iām trying to display a gradient map in Rhino3d, showing the change over time from orignal machined geometry.
I got the mesh split using V7.
Now, imma see if I can create an analysis mesh Iāve been after these last few days.
bbl.
keep getting errās even in V7
maybe something sub-D related will be inevitable.
CloudCompare may be useful. https://www.cloudcompare.org/
If you want pretty colors of the surface, you can make a solid from the two surfaces (old die and new die) and then use ThicknessAnalysis command on the solid.
i was heading in a similar direction, but havenāt finalized it yet. itās basically my last resort atm.
very interesting 
I really want it inside Rhino thoughā¦
