Bug in native Solid Subtract tool


For the record, I am using Sketchup Pro 2018.

This serves to report on strange behaviors in the Sketchup native Solid Subtract tool. I am aware that others have reported on issues before, but I could only find reports related to pre-Sketchup2018. Maybe the native Solid Tools have noe been updated for some years?
Again, for the record, both my original solids passes SolidInspector2 with “Everything is shiny”.

From left to right:

  1. The two original solid groups shown independently
  2. The two original solid groups, the smaller moved into position ready for subtraction from the larger
  3. Result after having used Sketchup native Solid Subtract tool
  4. Result after having used Eneroth Solid Subtract tool

The result from Sketchup native tool has a lot of holes, all of them FAR away from the subtraction part of the volume. How can this occur?

The result from Eneroth Solid Subtract tool is absolutely fine. Just perfect!

Unfortunately, in my experience the native Solid Subtract tool is unusable for anything apart from very simple structures. Trimble developers, feel free to debug!
My thanks to Eneroth for a very robust implementation of her tool.

By the way, this is my first testrun of the object, fresh from the 3D-printer.
And to everyone: Happy new year!!

KnifeHandle_21_test.zip (363.8 KB)


A couple of comments.
You don’t need to zip a .skp that is less than 3mb to upload it.
I’m curious why you needed subtract to make the shape when a couple of rectangles and pushpull would sort it out faster.
If you used more segments in your curve you would print a much smoother handle.


As to upload size: I thought it would be good to preserve space “on the other side”. Maybe that is not important?
As to “needing” subtract: No I do not, it just came out of the workflow at the time. And when I observed that the native Solid Subtract tool misbehaved so badly, I just spent some time researching the issue, trying to understand if I somehow misunderstood the usage. This is definitely a type of tool I need from time to time. And if this has been flawed for several years now, maybe it is time for Trimble to fix it? Luckily, there are some very talented users/developers out there…
Instead of subtract, I believe the way to go here is a combination of offset tool and Fredo6 push-pull by vector. But my issue here was really just to point out a native Sketchup tool problem, nothing more. Fix it Trimble!
As to smooth handle: Yes, you are right, of course. This was just a test run in PLA with a “half” handle to verify dimensions. The real one will be a much smoother whole handle in a much tougher 3D-material.
Anyway, thanks for all comments. We learn every day…