<Jack21>
seems there is an issue with 3mf export just had the file open when overwriting (export) and got Datei"E:/Seg.3mf" konnte nicht zum Export geöffnet werden
<Jack21>
3MF export finished: E:/Seg.3mf BUT IT WASN'T
<Jack21>
So it detects it can't write but say "export finished" yeah sure finished with trying - Ü
ochafik has quit [Remote host closed the connection]
<invultri>
Hi there, just made my first polyhedron, but it seems that openscad throws a bit of a fit when I try to do a difference on it. Is that expected / a limitation?
<teepee>
select thrown-together mode and make sure there's no pinkish colored faces
<teepee>
those have the points in wrong winding order
ochafik has quit [Ping timeout: 260 seconds]
<invultri>
thrown together kinda shows nothing
<invultri>
ah it did not like the empty difference around it
<invultri>
and some purple did show up, so that is good
<invultri>
and reversing order on one of the faces fixed it, thanks
<invultri>
does polyhedron mind if there are duplicate points in a face?
<Jack21>
points are not the issue - faces may
<Jack21>
but you can have connecting faces all using the same point or each using an own connection point as long the point value is equal
<invultri>
ok cool, in that case it might be not that hard to do a chamfer in 3d (smaller face would otherwise have one point less than the bigger one)
<Jack21>
just need to be closed so all faces need to be connected (watertight)
Jack21 has quit [Quit: Client closed]
Jack has joined #openscad
Jack is now known as Jack21
ochafik has joined #openscad
<invultri>
any tips on getting a drawing to dwg? seems that I will have to make several projections manually or something. Cause it seems to be an exercise of trying to make a projection from 3d to 2d.
<InPhase>
invultri: Note that duplicate points are risky if you calculate those points.
<InPhase>
invultri: It is easy to calculate points that are mathematically the same but not computationally the same, and then you can end up with a non-manifold polyhedron.
<InPhase>
It will even work some of time because of the sketchy grid snapping that goes on, but grid snapping can also induce a bigger failure by the same process.
<InPhase>
invultri: Also, allegedly dxf is the non-proprietary format that should typically be used instead of dwg. Although I do not personally work with either.
<InPhase>
invultri: I see you are using the master branch / nightly. :) You have a stray comma in line 44 that only works in current source versions.
<invultri>
InPhase: fair, but that is not was asked by the company making the L shape concrete prefabs :) (If I could get it in dxf there are plenty of converters judging by google). Main thing still stands, how to make projections.
<invultri>
heh I did not even noticed that
<InPhase>
Well there's the projection() built-in
<invultri>
yes that is the thing to go to, but that can only do 1 plain
<InPhase>
Well there's a cut parameter if you need slices.
<invultri>
and then different colors on them or something?
<InPhase>
But default it shadow-projets.
<InPhase>
shadow-projects
<InPhase>
Well I don't know what you're aiming for with these projections.
<InPhase>
Also... concrete? This does not look like a viable concrete shape.
<InPhase>
Plastic under low load, or metal, sure.
<invultri>
those things are 2m50cm tall
<InPhase>
What are they for?
<invultri>
retaining wall
<InPhase>
Well you have a 2cm wide fracture point along there on a very long piece.
<InPhase>
Jack: Yeah. I worked a bit with concrete, and found it can be surprisingly fragile when thin due to the brittleness, made worse when you add in some leverage. But then it rapidly strengthens with thickness and a good design structure to compensate for the leverage effects, especially when you can turn all load forces into compressive ones.
rvt has joined #openscad
<Jack>
i assume the thin structure only works because of cables adding compression and counteract any tensile stress
<InPhase>
Concrete blocks as an example become a bit hazardous when put sideways instead of with vertical holes. You can still put a reasonable load on top of them with that circular structure, but not any sudden forces nor construction scale loads.
<Jack>
but nice to see that oscad is used for building concrete structures
<InPhase>
It would be fun to have one of those concrete printers.
<Jack>
use a clay printer and fill with concrete - Ü
<InPhase>
Print clay and then build a bonfire around the building to bake it?
<InPhase>
I guess you'd probably burn more wood than it would take to build a wooden house. :)
<Jack>
would be interesting if that weight didn't deform when "sintering"