MakerGear Forum

Does anyone know of any software that will allow an imported STL file to be used in boolean operations?

To a very limited extent, Rhinoceros does. (Nothing particularly fancy though - just basic adding and subracting using meshes.)

Sketchup lets you do this. However, it needs to be a "manifold" shape which is often hard to maintain after manipulating a model so many times. I find I have to check if it's manifold every step along the way just to allow boolean operations.

Depends. Most software can do boolean operations to STL meshes. But if you're looking to reverse engineer a mesh into faces and arcs and stuff that you can then push and pull, only the big bucks software can do that. SolidWorks, for example, and I think maybe SpaceClaim.

OpenSCAD is what I use to run boolean operations on an STL file. I use it to pull in all sorts of complicated STL meshes and slice them, dice them, punch holes, add extra features, what have you. And it's free. And it was written by my friend Clifford Wolf, who is a fantastic programmer.

And you have to be a programmer with a good math background to use it don't you ? I remember looking at it a long time ago and was overwhelmed. My math is OK but I am no programmer. I was impressed with your chess set done in openscad though Tim !!! I even printed a few of them while testing out the hatchback wood filament.Very nice indeed.

Meshmixer and Meshlab are both free. Rhino has a 30-day trial I believe.

I use them all. Rhino makes fantastic booleans on hard surface geometry generated in CAD. Meshmixer is best for organic booleans. Meshlab will combine anything under the sun using poisson resurfacing.

It depends on what you are combining and what your desired result is.

Thank you all, I will look into these suggestions. The actual operation I want to be able to do, is subtract a STL(created by a scanner), from a solid to create a mold. I then need to add another scanned STL to another solid to create the back of the mold.

MagicEngineer wrote:The actual operation I want to be able to do, is subtract a STL(created by a scanner), from a solid to create a mold. I then need to add another scanned STL to another solid to create the back of the mold.

A programmer's frame of mind is certainly helpful for openSCAD, and so is a bit of math, especially geometry and vector multiplication. But for simple jobs like addition and subtraction, it can be pretty easy to set up. You would want to create a simple file that has something like the following:

To create a mold
Then you would have to figure out the size (a, b, c) of the surrounding mold and where to position it (x, y, z) relative to the part.
You would do this twice, so you get the two sides of the mold.

To add two STL files together, use "union() {...}" instead of "difference() {...}".

OpenSCAD is pretty good about doing a quick rendering of its own geometry, but imported STL files tend to look a bit weird until you select "render" in the OpenSCAD menu. Then it grinds away at the math for a while and gives you a proper result. Depending on the complexity of the imported STL file, it can take a long time to render. At that point, though, if it looks good, then you just export it to an STL file and you're done.

I've done some experiments in mold making. It's actually a little tricky to do it completely 3D printed because you have to be extra careful about overhangs, or even vertical walls. The print doesn't have the give of a silicone mold. Use gratuitous amounts of mold release. viewtopic.php?f=6&t=224 (I wonder whatever happened to Toby, he was very helpful).

You should put up a link to your object (if it's not private) and see if anyone wants to show off their talents.

Or, you can just try this: http://www.thingiverse.com/thing:31581