What workflows are people using for making dimensioned plan drawings of a 3D object?

Initially I tried using the Dim tools directly on the 3D object, but discovered that I couldn't do things like getting a Radius dimension for the diameter of a hole drilled into a non-planer surface (like a radial hole going into the outside diameter of a cylinder) because the edge that I'm trying to dimension isn't planar, and so the Radius tool can't figure it out.

I also had problems when trying to dimension directly on 3D objects because I needed to make a bunch of duplicate objects with each being rotated to present the correct face in one ortho view. This got a little confusing like when I had to make a design change what with deleting all the 3D duplicates and trying to align the new rotated 3D object with all the existing dimensions.

I tried getting all my views off of one 3D object using the built-in ortho views and changing the cplane, but it turned out that I couldn't control this well enough to get the particular 3rd angle projection relationship between views that I was aiming for.

Another problem I had with the 3D approach was that dimensions would get buried inside the 3D object because of where I was snapping or there would be Z fighting even in ortho views. So I'd have to manually pull the dimension objects toward the camera.

So, now I'm trying out make2D where I rotate the 3D object and make multiple projections from the Top view by rotating the object each time. The problem I have now is that the projections aren't accurate enough to play with the Radius tool. In other words, Radius won't recognize a projection looking along a fillet as an arc.

Has someone figured out a nice way to make a drawing with multiple views and Radius dimensions?

- Peer

Hi peer I use the Make2d4Views script dimension that and output PDFs could be simpler after years of using solidworks and rhino to make drawings I now do 90% of drawings in MOI and the PDFs are easy to read and fully featured.

Hi AlexPolo,

Thanks for your fast reply. How would you get numerical values for D and R in the attached 3DM?

- Peer

Hi Peer, the problem you're running into here is that the curves that look like a circle and arc are not precise circle or arc analytic curves, they are general spline curves that closely resemble a circle and arc but not quite to the (rather tight) precision level that MoI currently uses to detect if a curve is the shape of a circle or arc.

To solve this currently I think you would need to replace D with a 3 point circle and R with a 3 point arc.

You can do this by selecting the circle, then run Draw curve > Circles > 3 pts, place 3 roughly equidistant points and then hit delete to remove the original curve. Same thing with the arc except using the 3 pts Arc tool.

I guess there are a couple of possible ways to improve this so you wouldn't need to do that. One possibility would be to loosen the tolerance used to detect if any curve is a line, circle or arc.

Another possibility could be to allow a radius dimension to be put on any curve with the value using the curvature at the picked point. Rhino does this but it seems kind of dangerous.

Or another could be to do some shape analysis on the result of the projected curves in the 2D drawing generation and replace with exact circles and arcs at this spot. This seems like it may be the best way because the other methods could lead to a false sense of accuracy.

- Michael

Hi Michael,

I appreciate your thorough reply. I guess for now I'll manually re-draw with the arc and circle tools like you're suggesting, or maybe I'll continue to manually key in the dimension values using a leader like I have been.

Regarding the "shape analysis" option, are you saying this is something I could do by writing a script? Sounds pretty tricky.

- Peer

Hi Peer,

re:
> Regarding the "shape analysis" option, are you saying this is something I could do by writing a script? Sounds pretty tricky.

I'm saying it's something I could do to the projected curves in the drawing generation.

It's possible to do it in a script, it's fundamentally just evaluating a bunch of points along the curve and see if they are close enough to a circle. But it can be tricky to do it well.

I'll give it a try as a part of drawing generation.

- Michael

Here is dimension drawing in MOI and yes the outer radius I achieve by tracing 3pt curve in position over the render.

Thanks for the example AlexPolo.

- Peer

Hi everyone,

You could imagine making automated printouts like this with a few dedicated tools. In this case, I did it for fun, in a very home-made way.
I'd have liked to use coordinate dimensioning, but with my custom UI it doesn't work.



See link below
http://moi3d.com/forum/index.php?webtag=MOI&msg=11109.1

Note: I made this drawing from a drawing and a piece to create offered by TITANS from CNC: Academy Site.
In the end, MoI3D (for both the part and the drawing) worked quite well. As for me, I do it for fun, for the pleasure of 3D and to make my neurons work!

Hi Zooen,

Nice drawing :)

Re:
> I'd have liked to use coordinate dimensioning, but with my custom UI it doesn't work.

Do you mean this plugin?

http://moi3d.com/forum/messages.php?webtag=MOI&msg=11115.1

I can imagine that adding the icon might not work, but if you set up a shortcut key for "Ordinate" does that work?

- Peer

Hi Peer,
>Do you mean this plugin?
Yes

>I can imagine that adding the icon might not work, but if you set up a shortcut key for "Ordinate" does that work?
I did this and it works. Thanks

I noticed that it is therefore necessary, to carry out the dimensioning, to move the supposed (chosen) origin of the coordinates of the element that we want to dimension (the local 0.0) to the origin of the world (the 0.0 overall).
In the example case of my plan above, I have 3 local origins. So, 2 movements of all the elements (entities) created.

Hi Zooen,

Glad to hear you got the plugin working.

It sounds like you're moving the view of the part to the world origin adding the dimensions, and then moving the dimensions and the part away from the origin. I hadn't thought of doing it that way.

I set up local coordinates using the CPlane tool which lets me snap the coordinate system onto the part.

http://moi3d.com/4.0/docs/moi_command_reference5.htm#CPlane

For each view I have to set the local origin again. One problem with this approach is that there's a bug in my code and with some orientations of the local coordinates I get an error message, so maybe your method is better until I get a chance to fix that.

- Peer