veteran BobCAD users -- 3D

[inthedark]

I have a project that I did in 2D and rotated the part several times. I thought it may be better to do a full 3D CAD and cut the part using contouring, to save time.

However while using solids, there are some shapes and contours that I just can't get to come out. I wish the solids had a diamond shape. The shape I am looking for is a basic diamond shape 1.75" thick with .25 fillets.

Needless to say trying to get my solid 3D design, has destroyed my timeline. But then I'm just not one to give up on a theory.

Do you ever deal with this?

I am ging back to 2D and rotating the part as needed through the milling process.

I believe my experience with V19 or BobCAD in general may be my delimma.

Thanks,
Kenny

[Konrad]

I just have an idea,
could you do your solids on Rhino [ free demo Version] and Import to Bob CAD?
Konrad

[inthedark]

I'm not familliar with it but if the learning curve isn't too great I will give it a shot.

Thanks

[cely]

InTheDark

I'm assuming your diamond solid is made up of some number of N-sided planar surfaces, somewhere out in 3D space.

Here is a script that builds an N-sided planar surface. If your diamond has 5 sides, you will have to run the script 5 times.

Each N-sided planar surface is defined by the XYZ location of each vertex. That is, the data is entered in 3D space.

The script asks for the number of vertices and then asks for the X Y Z data for each vertex.

Gotcha #1. All vertices must be entered in order. No jumping around.

Gotcha #2. All the vertices must lie on a plane or the script will fail.

Gotcha #3. The script instantiates points and lines and then cleans up after itself. If you already have point and lines, they will be deleted.

Gotcha #4. The script does a Boolean Union. If you already have a solid on this layer, it may get modified.

Here is the XYZ data a 1.75", 5-sided pyramid. The base is a 4-sided polygon. The 4 sides are 3-sided polygons.

0 0 0
1.75 0 0
1.75 1.75 0
0 1.75 0

0 0 0
1.75 0 0
.875 .875 1.75

0 0 0
0 1.75 0
.875 .875 1.75

1.75 1.75 0
1.75 0 0
.875 .875 1.75

1.75 1.75 0
0 1.75 0
.875 .875 1.75

This would be an easy function, if I could ever figure out how to pass an array to a function.

Good Solids To You

PS You have to change the name of the script from POLYGON.TXT to POLYGON.BAS to execute it.

[CNCdude]

Cely, you have been a great help and I appreciate your emails to me. Hope to see everyone at Westec. We have added a Space Plane to our booth that is going to be something great. I have just completed the V19 upgrade training professor CD videos and a new interactive workbook as well.
CNC Dude

[keithorr]

Originally posted by inthedark I have a project that I did in 2D and rotated the part several times. I thought it may be better to do a full 3D CAD and cut the part using contouring, to save time. However while using solids, there are some shapes and contours that I just can't get to come out. I wish the solids had a diamond shape. The shape I am looking for is a basic diamond shape 1.75" thick with .25 fillets. Needless to say trying to get my solid 3D design, has destroyed my timeline. But then I'm just not one to give up on a theory. Do you ever deal with this? I am ging back to 2D and rotating the part as needed through the milling process. I believe my experience with V19 or BobCAD in general may be my delimma. Thanks, Kenny

I use 3D features when nothing else will do. Otherwise, I offset a profile (to accomodate half the tool diameter) and make a manual toolpath for symetrical half mold cavities. Machine time is much less than letting the program decide where to cut. CAD/CAM is much faster on a lot of the shapes I make if I ignore the bells and whistles.

[inthedark]

I was able to get what I wanted, thanks for your your help and suggestions.

Kenny

[CNCdude]

Good point,
I will recommend that we add more primitive solid shapes. We will also be adding the ability to apply a tapered edge to a solid and to the extrude function. This will also contain an extrusion with a twist. Good stuff coming up!
CNC Dude!

[cely]

kiethor,

I'm relatively new to CAD/CAM and BobCad, so this is just my opinion.

I prefer designing in solids because I can use the Boolean/Difference function to see if there is any part interference and because the fillet function is 3 dimensional. It may not be the fastest way to design a part, but part of that is my lack of experience.

I agree, the solid toolpath tool is limiting, so I Extract Edges to create a line drawing. And then use the regular dimension and toolpath tools. Since everything I do is mostly filleted rectangles with lots of slots and holes, this works pretty good.