Simulated Welds

Rhino V.4

Does anyone have a way to run a fillet around the juncture of 2 tubes 90 degree to each other and touching? (top example) Fillet would need to go all the way around.

And just a general weld simulation? (lower examples)

I’d try FilletSrf, possibly with Trim=No, depending on what you want to do, and then some bumpmap, (assuming rendering is the goal) UV mapped onto that surface. I’ll see if I can make an example here in a minute.


FilletSrf works when the two tubes have some overlap. When there is a single point of contact, noting gets filleted.

The surfaces do not need to touch for FilletSrf to work as long as the radius of the fillet is large enough to bridge the gap.

FilletSrfFakeWeld.3dm (187.0 KB)


Another way using Pascals method first, after that i rebuilt the fillet surface and used _MoveUVN to deform every second control point of the middle row in U and N direction…coupled with some grip randomisation of course to avoid using a bump map :wink:

Welded.3dm (105.0 KB)


pascal and clement

can’t use either. 1st line, 1st post. “Rhino V.4


V4 versions attached

FilletSrfFakeWeldV4.3dm (196.2 KB)

WeldedV4.3dm (639.3 KB)

thanks davidcockey for the assist


that is exactly what I’m after. can you walk me through it from beginning to end?


sorry for the V4 file, been to busy and overlooked that :wink:

To do the weld like surface, you can go this route:

  1. Make surface using _FilletSrf as Pascal suggested, use the _Trim=_Yes option
  2. Use _Rebuild, change U Count to 100, leave V Count as it was, delete the original fillet
  3. Turn on the control Points for the new created surface
  4. Select every second control pt in the middle Row along the U-Direction (manually)
  5. Use _MoveUVN to change the point locations in N and U direction
  6. Leave the moved control points selected so you can apply the script in the next step
  7. To get some randomness, this script (works in V4 only) could be used
  8. If your fillet was closed, check near the seam if it is still clean, if not, you could select a few control points there and use _Smooth to clean it up.

Does this help ?


Got it. I was successful in working through it, but mine turned out more like dragon scales. :slight_smile:

Looks like I’ll have to spend some time with _MoveUVN to get the look right. Then somehow come up with a way to make same N and U changes from weld to weld to get some consistancy.

thanks clement

I think you almost got it, you might try to smooth in the MoveUVN dialog as well, then move along N and U again. It took me while to get it close to your picture.

Btw. welding is great in Rhino, how would you get that ? :



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Just leave it outside for a few weeks in a maritime climate…


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…saved on a 3.5’’ Floppy drive :wink:


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Gotta love the nerd humor.


I’m attempting to draw a 3D TIG weld for one of my projects and found this thread. First I tried out the _MoveUVN technique, but I couldn’t get it to look right for the stack of dimes effect. That being said, even this is much better than a simple smooth surface for the weld bead:

Then I tried out a totally different approach that yielded something I’m much happier with, but it’s very labor intensive:

I’m still playing around with it, but I wanted to share what I have so far.

Seems like displacement mapping could work for this .

Displacement weld test.3dm (152.2 KB)


A good friend of mine suggested the same thing when I was talking to him about this project. I’ve never used displacement maps before, so that’s the next thing I’m going to play with.


I have done the 'stack of dimes' weld using a trick that you can find somewhere in the online tutorials for making stitching. 
You just have to create a linetype that will let the individual round capped pipes overlap like they would on a weld. I'll see if I can find my example. It looked pretty good rendered and I've even booleaned the whole thing into one polysurf and run FEA on it.

I think this is what Joseph_Culbert suggests as well, but if it is just for rendering/looks then I have curve arrayed (with overlap) a disk around the intersection of the pipes, boolean all the disks, custom mesh to get even density, extract render mesh, then smooth, then trim out the inside mesh if needed:


I guess realism depends on the disk geometry…

Maybe a more controlled method is to go ahead and fillet/blend the pipes and then flow the disks on the blend surface. I had some extra time so I tried it out spending more time on the disk:

This one was booleaned/meshed before flowing and it was much faster to flow:


Smoothed a couple times after the flow operation caused some pinching in the center.

Waiting for traffic to clear, with some positional randomness in the disks pre-union:


Thanks for all the amazingly useful tips here. I’m still very new to Rhino but have a fair bit of Sketchup experience.
I was looking for help with the welds on this Rocketeer helmet (just a practice project).
I settled on the stack of dimes arrayed along a curve tip. I turned my dime into something like a red blood corpuscle shape which I think has worked quite well for a quick weld simulation.
Thanks again