I am having trouble joining two polysurfaces.
Although there are two nice tutorials on youtube that address this topic (Intersecting multiple pipes + Y branch modeling)
they do not offer a solution to my problem.
I am dabbeling in creating a pendant and plan to send it to shapeways for 3d printing.
Hence, the file should be .stl
Does anyone have advice on how to go about this?
(Will a “group” of polysurfaces suffice or must all parts of the model be joined perfectly for proper 3d printing?)
Hi Octavia- I would assume the latter- some systems can handle inter-penetrating solids, but I do not think that is the rule - certainly Shapeways can tell you.
If you can post your object so far, we may be able to suggest ways of making the transition surfaces.
I watched another batch of tutorials and was thinking that maybe I should go this route with my model:
Sweep1 command --> Extract wireframe (Curve From Object) --> split the wireframe at those critical points --> explode my section curves --> Sweep2 and build the transitions manually.
What do you think? Is there perhaps a more elegant approach?
yes, something like the transition in your picture (the upper model) - The Y-Branch
and for the X-like intersecting pieces a some kind of trim-the-inferior-and-blendsrf-with-superior-polysrf-operation…
Add-boolean does not work because the base of both sweep-geometries are located at the same height in z-axis, I guess.
Ok, so, I think it is a matter of planning a bit- you’ll need to decide the limits of the transitions at each location and trim back the surfaces to make the required gaps to fill with the transitions. It will be a bit of work- but you’ll get the idea. The attached is by no means clean enough or complete, but just by way of showing you how you might approach things. transition_Pg.3dm (452.2 KB)
thank you for taking the time and handling the file!!
So did you basically just trim the polysurface with a geometry and the blendcrv the curves?
And how about the transition in the lower left model of your previous picture?
Did you perhaps sweep1 with only one half (trimmed) of a section curve on “each side”/the trunk and joined or blendcrv-ed it?
What do you suggest is the most efficient way to join the x-intersecting part of the 2 polysurfaces?
Using simpler section curves (with no fillet, just corner) -> sweep1 -> -> and then manually rebuild the intersecting piece --> filletedge chained edges?
Or are there more efficient solutions?
Hi Octavia- I’ll attach a little cleaner file that will give you an idea how to construct this sort of thing. One thing that I noticed is that the small rounded edges on your sweeps are no at all tangent to the upper and side surfaces everywhere- that will make life difficult in adding details. I would make this as a hard-edged shape and kill the edges with Fillets or Blends after the fact.
Stratosfear has reworked your design much more extensively- pay attention to his approach, he’s good at this.
One thing I think will happen as you go is you’ll think more clearly about exactly what you want the design to be like - as posted, your idea is incomplete, you need to have a good idea what those transitions really look like, then it becomes easier to come up with strategies for surfacing them.
hmm, what do you mean by “small rounded edges on your sweeps are no at all tangent to the upper and side surfaces everywhere” ?
How do I recognize if my fillets/round edges are not tangent?
Yes, you are most probably right. I was also thinking about making those sweeps with hard-edged section curves, blend them and then apply a filletedge.
Basically, I had a transition like that in mind, although in this picture it is a ring:
Thank you for that “cleaner” file, but to be honest I do not get any wiser as to what methods or commands you have used just by looking at your model.
And I can not follow your steps just as easily as I could if this were 3ds max + modifier stack.
I suppose you exploded the polysurface, trimmed the y-branch and did a couple of blendcrv commands and the patched or joined it? yes or no? Am I close?
Could you also please break down or at least give some hints on how you modelled this 2nd transition:
It looks nice as well and I would be also interested in that technique.
As to the second transition, the x-intersection, this (your file) is exactly what I had in mind, but again I am just vaguely guessing how you might have done it.
Did you explode the thicker-arm-polysurface, trimmed it with the thinner arm or a copy thereof and then blended the edges?
I am also somewhat confused about “Stratosfear has reworked your design much more extensively- pay attention to his approach”
Is a Rhino-Pro able to recognize the modelling-technique by merely looking at the isocurves of the transition? If so, then I am really sitting in the back of the class…
I am a beginner, so sorry for all those questions and thank you for your patience
Hi Octavia- I’ll make a blow by blow file for the first transition - the second one (‘X’) is done with FilletSrf (surface to surface fillet tool) then trimmed after all these are made. I had to replace your edge ‘fillet’ surface there thoug because they were not tangent - see the image below- the red is a section curve through your object with a shaded closeup on the right:
I pointed out stratosfear’s input because, yes, as you suggest, 9/10 of the battle is figuring out a clean and logical arrangement for the surfaces, and he shows that nicely in the image.
thank you very much for your effort and the file!
Sadly, I have been ill since last week and did not feel well enough to boot up my computer and have a look.
I will though in the weekend.