BricsCAD basics: Distance contraints on extruded cylinder

Carlos Fuentes

 Hi there,

I'm new to CAD programs, and came to CAD by way of programming and OpenSCAD.  I think I"m approaching modeling wrong, because I'm having trouble doing the simplest things.  Can you help?

Specific case:  I'd like to center an extruded cylinder on a face (see the screenshot for where I'm heading with this).  Here's how I went about it:

# In 3D modeling, I drew a rectangle and extruded it to create the box

# Still in 3D, I drew a circle on one of the faces and extruded it.

Now I want to center the cylinder on one of the faces.  I was assuming I could create a 3D distance constraint between the center of the cylinder/circle and one of the faces/sides, but I could not get it select the center using 3D constraints.

On the other hand, the 2D constraints understand the centers of circles.  However, they would highlight in red, and attempting to select any 3D points gave me an "Invalid coordinates" error.

What am I doing wrong?  How would the experts out there go about modeling this very simple shape?

PS - Is there a better place for me to be asking these beginner questions?

PPS - Are there any good resources for learning how to work with a this style of modeling?  The official videos only cover very specific features, and not how to use the features together.

Dmitry Ushakov

Hello Carlos,

3d constraints can only be created between faces and edges of 3d solids.

Distance to a cylindrical face is measured as the distance to the cylinder's axis.

It is described in BricsCAD V15 User Guide/Creating Entities/Direct Modeling/3D Constraints.

Best regards,

Dmitry

Louis_Verdonck

Dear Carlos

You can use Entity Snap tracking (midpoint entity snap) to position a circle at the center of the solid face, which is then extruded to create the cylinder. See the attached video.

CreateCylinder.gif

Carlos Fuentes

 @Dimitry Ushakov, that did it, thanks! I don't see where it says that the distance is to the cylinder axis, but that makes sense.

Scott McKenzie

Attempting to constrain one 3D object's centroid in relation to another's was a task that I had come up against quite some time ago, although I used the example of centreing a cube atop another, a cylinder is much more difficult.  Check this post for some ideas: https://forum.bricsys.com/discussion/24598  There were a few solutions but I still think the best option requires additional tools in the BricsCAD system (each object, mechanical component and group of mechanical components has an XY, YZ and ZX plane that we can constrain to, and is located at the centroid of those the items).