Aligning STL objects with only few same "spots"

[[Al...]]

Hi guys!

 

I admit I am rookie and trying to use GOM for first time, saw some clips but I can't seem to figure out how to align two objects which are almost same but are of course not. What I would like to see them aligned by inner hole design and to see if there are any differences between them. All other surfaces will be different since one file is modified from another but only on the ouside aka teeth. But I want to check if holes are perfect match or not but GOM won't align them...any idea how to do it? TIA.. I hope from photos you will understand what I want to align...

[[Na...]]

Hello Ales,

in principle you need to align a nominal element with an actual element. You could create cylinders on your nominal part and on you actual part and click on the plus sign on the top right and chose alignment by geometric elements. However, all cylinders are nearly parallel, which means not every degree of freedom is blocked. You could try to create a point in each cylinder (section point from a plane and cylinder axis for example). With points you can use an RPS alignment for example. Are you screenshots after the prealignment (also available on the plus sign)?

Regards

Nanno

[[Al...]]

This is prealigment....

[[Na...]]

Please try to construct -> Cylinder -> Nominal, measuring principle fitting Cylinder (On the blue nominal part). Or are those cones? Are there some flat areas on the backside? This would help with creating points at a specific distance to the plane on the cylinder axis.