Can anyone tell me why I can only subtract the attached file in one direction? Both parts are solid components and I am trying to keep (2) the outer shell with slots down the sides from the inner part (1), but the inner is removed without creating the cuts. If I reverse the order, the outer shell cuts the inner shape and goes away as expected. Any help is appreciated. (Pro 2025)
Thanks, Rodney
Coaster Holder 2 - 3.5x3.5 in.skp (2.0 MB)
Subtract is only supposed to work in one direction. With the native Subtract the mantra is, “Subtract this from that.” Click on the thing that does the cutting and then the thing being cut.
Hi Dave, yeah I get that 
and have used it before, but with the attached model, if I select “this” (cut out) and then “that” (Holder), then “this” disappears and “That” remains uncut. Any thoughts? BTW I tried reversing this and that and that worked, but not what I was after… hope that made sense… lol
It’s a matter of scale. Tiny face issue related.
Just scaling up by a factor of ten makes it work.
Hey Box, wow! that actually worked. Super glad I asked, I would never have gotten there 
Thanks dude!
Nice.
If you are making things for 3d printing it is best to work in metres and treat 1m as 1mm.
You can then export the stl as model units and your slicer should import it as mm. This avoids all the tiny face issues and even allows you to work with 96 or so segmented circles (more than 96 is overkill usually) without the software telling you too many segments for the size of curve.
