Need help drawing unusual object.

Jim Canale

 Hi everyone.  I'm still not very familiar with the 3D tools of BricsCAD, because most of my work is 2D only.

I have to model a very odd shape.   I have attached a picture of it.   The V-shaped cuts in the disk reduce in depth as you go from the edge of the disk to the center.   I am not concerned about the threaded hole in the center.    I  assume I will probably be creating a disk and a triangular section, then subtracting the triangle from the disk.  But I have no idea how to create the triangle, or align it.  

Ideas anyone?

Jason Bourhill

Hi Jim,

There are numerous ways you could go about to produce this object. Commands to explore:

• _UCS. Short for User Coordinate System. This command allows you to re-orientate your drawing plane. From there you can draw using the commands you're already familiar with (_LINE, _PLINE, _CIRCLE) relative to your constructed UCS. To avoid getting confused, recommend that you use _3DCONTEXT. The grid (F7) will give a visual indication of your current UCS allignment. I would also make sure _UCSICON is on, as this provides another visual indicator.
• _PLINE. Generally 3D objects start with a closed 2D object, which you then _EXTRUDE, or _REVOLVE to create your 3D solid. You can configure your _SETTINGS to specify whether the 2D primitives are deleted on creation of the 3D object (DELOBJ).
  
• _ALIGN. This command offers an alternate way of positioning objects, which avoids the need to create multiple UCS.
• DUCS (F6) can also be useful. When turned on it will automatically align your UCS to the face of the object your cursor is positioned over. You could create a 3D solid, such as a cube for construction purposes, that would allow you to quickly orientate your UCS without using additional commands.
  

Hope this is of some help.

Regards,

Jason Bourhill

CAD Concepts

3dShape-Triangulated.png

Jim Canale

 Jason,  I think I understand the use of UCS.  But I don't understand how you made the triangular shapes.  I don't see a 3D command for that.  And how did you orient them at an angle to the top of the disk?

Patrik Sparrman

Jim you can just make a triangle and extrude it and then rotate and move it into position. I Think Jason is close but I think you have to make the wedges from the center and out and then tilt them slightly . Finally I placed a small cylinder in the center and subtracted it.

wedge2.jpg

wedge1.jpg

wedge3.jpg

Jim Canale

 Thank you both.  I will keep trying.  I am realizing I am facing two major problems.  One is I don't have a good video card (or good drivers).  Too many artifacts and wierdness in the display.    The second is I have worked 2D so long, that I am having a great deal of trouble keeping oriented in 3D space.