Compare tool : how to not miss really small differences

Patxi_LZ

Sometimes I have to repair in-context references and I want to make sure that the part is the same as before.
In order to do that, I use the compare tool with the previous version of the part.
I check if the blue or the red color appears, but sometimes the modification is really small, for example an error < 0.1 mm in a hole position or depth.
I am always concerned that I miss a difference.
Is there a way to know if there is a difference prior to looking for it ?
Is it possible to make them more visible ?

bradley_sauln

You could also try to use interference detection by putting both parts for the two different points in time in the same assembly.

But the best way to approach this would be to use named positions along with your in-context design to make sure the parts you are focused on return to the same exact place. This will be useful for both un-mated and fully mated assemblies.

MBartlett21

@Patxi_LZ
You can also look at the feature list, which will show comparisons with that.

mahir

I'm not too familiar with the Compare tool. But an alternative is to perform a boolean subtract of one body from the other. If there are any differences, they will show up as a separate part in the parts list.

Patxi_LZ

MBartlett21 said:

@Patxi_LZ
You can also look at the feature list, which will show comparisons with that.

After my modifications, even if the parts are the same, the compare tool tells me that some elements of the feature list are different.

mahir said:

I'm not too familiar with the Compare tool. But an alternative is to perform a boolean subtract of one body from the other. If there are any differences, they will show up as a separate part in the parts list.

I think I will do that. The process might take more time, but at least the result is clear.

bradley_sauln said:

You could also try to use interference detection by putting both parts for the two different points in time in the same assembly.

But the best way to approach this would be to use named positions along with your in-context design to make sure the parts you are focused on return to the same exact place. This will be useful for both un-mated and fully mated assemblies.

I am not sure that I understood the solution. I put both parts in the same assembly, I fasten them to the origin in the same way and I check interferences ? I did not get how named positions can help me. Moreover, can I make the complementary of the interferences ?

dean_brettle

I recently created a custom Compare feature that you might find useful. It does the boolean subtract mentioned above, in both directions. In your case, you'd use it by creating a version before your changes and then using the compare feature to compare to that version. If there are differences, it will create composite part(s) containing them. I've added an example Part Studio demonstrating that.

romeograham

@dean_brettle That is a nice compare feature! However, I can't get it to allow me to select a Part Studio from an earlier Version (of the same document) like your example.
In fact, when I select a Part from Main (the current Workspace) and then try to select an earlier version of that same part, the Part Studio is not even visible (all the other ones are).

Do you see any issues in the code that might cause this? Again, it doesn't seem to be working like your example Part Studio you show above.

thanks!

dean_brettle

Sorry. I realized after my post that you can't compare to an earlier version of the Part Studio containing the Compare feature. Instead, you need to create a new Part Studio just for the comparision. In that new Part Studio, add a Compare feature that compares part(s) from 2 versions (or a version and workspace) of the Part Studio in question. That's what mine example is actually doing. The Part Studio being referenced in that example is actually another Part Studio in the same doc.

albert_mostuve

In this situation, a more rational solution may be to perform a logical subtraction of one body from another, because if there are any differences, they will be displayed as a separate part in the list of the same parts.

romeograham

Thanks @dean_brettle for the explanation. I agree that's what your example was doing...just didn't realize that's the only way to do it.
I like the composite parts / colour scheme for identifying bits that are unique to either A or B.
Thanks!

dean_brettle

albert_mostuve said:

In this situation, a more rational solution may be to perform a logical subtraction of one body from another, because if there are any differences, they will be displayed as a separate part in the list of the same parts.

That is, in fact, what the custom Compare feature does. It actually does the subtraction in both directions.