Boolean operations in Carbide Create

Wrote up a little bit about this here: https://www.shapeoko.com/wiki/index.php/Carbide_Create_Basics#Boolean_Examples

For everyone’s convenience:

====Boolean Examples====

For selections involving only two objects, it is worth examining all the possibilities:

If the rectangle is the key object (indicated by its being drawn with a dashed line):

=====Boolean Intersection=====

(For this operation, which object is key does not matter.)

=====Boolean Subtraction (Rectangle as key)=====

=====Boolean Subtraction (Circle as key)=====

=====Union=====

2 Likes

Another piece of news. I talked to Rob about the fact that there are just some size geometries that are more difficult to work with (e.g. Putting rounded corners on some squares), he stated that there will be a big update soon (no time frame) making it easier to use. I’ll try to get some additional when I visit on Wednesday (5/31)

2 Likes

Until that’s released, I documented a pretty straight-forward technique for doing this at:

1 Like

I sense that you doubt me. Haha. When I get back home I’ll post the WD40 Wood can holder CC File. I bet I have at least 6 hours of JUST trying to put a 1/4" rad on the corners.

Good luck.

@WillAdams, if you get a chance here is the file that I have failed to get CC to put for 1/4" rad on the corners of the large square. IF you are successful, PLEASE show me what I am doing wrong. PS First I made the 2.625 square, then I tried to put the rad on the 4 corners then I drew the second small rectangle, etc.

http://community.carbide3d.com/uploads/default/original/2X/2/280f59186052dbafa77e8e299dfb138d2481894b.c2d

When I opened that file, there was only a rectangle (3.1" x 1.3") and a circle (0.892" radius)

The way I would do this is to draw two rectangles centered on 4,4, one 2"x2.5, the other 2.5"x2":

Then draw in four circles:

Union all 6 objects and then scale the selection to 2.625":

WD40_2.c2d (111.8 KB)

Because it was created in CC Ver 283 sir

I figured as much. Anyway, to make it explicit, the thing which you were doing wrong here was using a dimension which didn’t line up on the grid. To address this, either:

  • change the grid dimension to 0.125"
  • reduce to align on the grid, then scale up afterwards (as shown above)

I think you mean to change the grid to 1/16 and that’s where the problem starts (I think) because the grid spacing is 3 places and 1/16 is 4 places (ref 0.0625), so the grid never lines up to the edge of my 2.625 square.

So the grid AND the geometry MUST line up perfectly (Mathematically) for the boolean function to work. Hmmm So I would need to change my design to work on a 0.062 OR 0.063 grid, that doesn’t seem right but I know it’s free software.

Am I right if am I missing something?

Yeah, that’s pretty much it. I always forget about the precision limitation — to work around it, work at 10x larger, then reduce? (or switch to metric?)

That said, for a 1/4" diameter, a 1/8" radius / grid should work.