Hi,
ZoomNaked says no naked edges.
Rhino 5,7 and 8 all say so.
does that mean its watertight ?
We had webbing forming in the bars.
Now my printer chap says solved it,
Anycubic Slicer v3
and Prusa
and Fusion360 all said was NOT WATERTIGHT.
they then repaired it, now it prints without this webbing.
whats going on ?
what other command should I use to check an object is good to go, before sending for 3D printing ?
Explode the object
Select all the parts
Join
Result will be a closed polysurface without non-manifold edges. (At least in V8.) Note: This proceedure works with the topology of this object. It may not work work with other non-manifold topologies.
Switching to shaded mode took a few seconds in V8 for me.
Thatâs not a reliable method to determine if an object is really closed. Properties or What will tell you that as will SelClosedSrf or SelClosedPolysrf. Non manifold objects are considered open in Rhino.
The results of What as to open/closed status can be inconsistent with the Sel.... commands: What considers this object a âclosed non-manifold polysurfaceâ. SelClosedPolysrf does not select this object. SelOpenPolysrf selects this object. SelNonManifold selects this object.
The volume/mass properties commands give a warning before showing their result:
For this object the results of those commands are correct (same results as when the non-manifold edges are removed.) This is not surprising given the topology of the objects. Volumes are fully enclosed. The non-manifold edges are shared external corner edges of volumes.
Geometry:
Valid polysurface. closed non-manifold polysurface with 3122 surfaces.
One or more surface normals are not oriented.
Edge Tally:
90 seam edges
7675 manifold edges 80 nonmanifold edges
= 7845 total edges
Edge Tolerances: 0.000 to 0.001
median = 0.000 average = 0.000
Vertex Tolerances: 0.000 to 0.001
median = 0.000 average = 0.000
Render mesh: 3122 meshes 60461 vertices 47874 polygons
Created with fast meshing parameters.
Analysis mesh: none present
Geometry UserData:
UserData ID: 769DDDD4-1756-4c95-A026-8E975D704AEA
description:
saved in file: no
copy count: 0
so in a nutshell what command should a beginner run to see if something is good to go for 3D printing ?
I have a figure which is just curves, no straight lines anywhere, its a many faces .stl mesh file from the scanning company. They say watertight though one printing bureau said not watertight. 1 out of 20 or so, rest happyâŚ
what command again to assure me and all, that its watertight and ok for 3D printing. ?
Interesting. I guess I never paid close enough attention to the descriptions saying âClosed non-manifold polysurfaceâ. I guess that means it looks at no naked edges and says âOK, itâs closedâ. Not sure if this could be considered to be a bug or not, especially as it doesnât match with SelOpenPolysrf/SelClosedPolysrf⌠I guess I would prefer it simply to say âNon-manifold polysurfaceâ without reference to open or closed.
Exploding and rejoining does get a closed (supposedly) manifold surface. I say supposedly, for as @jeremy5 mentioned in the other thread, these types of structures - where vertical corners just âtouchâ - are inherently non-manifold - more than 2 edges at a single joint. So in this case Rhino is hiding that from you.
If you export the exploded/rejoined object (the one that Rhino says is closed/manifold) as an .stl, and then reimport the .stl, it will be non-manifold. This is normal, as when an importing program re-assembles the âtriangle soupâ that is an .stl, it will automatically make non-manifold edges at those exact spots.
Some 3D printer software may be able to deal with this, some not I guess.
The exploded/rejoined model did take some time to shade here in V8, as did the .stl export.
Plus the âtaperedâ piece on the left side with the holes in it also has only a tiny strip of greater than zero area contact with the rest of the object - will probably separate while 3D printingâŚ
Hi, yes this was a WIP and is now SR4 with the zero contact as 0.5 !
I am concerned though, this with those deliberate 3 or more faces joining at one edge, is a non-manifold waiting to happen.
I have exploded and then run join, in Rhino5, and lost the top surface somewhere. repeated in Rhino8, and it also vanished 2nd time, but not first. (see other post).
I have then done it face by face by face then attempted all, and bingo.
BUT the soup as is referred to of all this as .stl can cause mayhem.
We need a fully accepted object for 3D printing, especially as it is a calibration item.
Just how should I send the non-manifold item if he or anyone requires .stl ? the asked for file type normally ?
You say .obj is better than .stl
A 3D printing company always ask for âwatertightâ. Wish theu would say prior sending
check for naked edges
check for non-manifold edges
dont look at properties and for the word closed
For users of Rhino.
Run ZoomNaked
Run SelNonManifold, if anything gets selected then
Run ShowEdges selecting Non manifold
to fix, explode then join, if surfaces vanish, undo then select and join the former vanished one to another adjoining, then repeat, then try for remainder.
This is the first time I have come across this. I will need to revisit other test items.
Should this be a sticky as lots are into 3D printing.
Dont want Rhino to get bad name.
No doubt other progs are also faced with the same issue.
Hi,
just doing an .obj from rhino8, and i see a number of choices and tabs with choicesâŚeek
going with default,
but what are the correct or best settings in the options panel ?
also should I click save small or might that introduce any issues ?
anything else like geometry tick ?
stl was 13mb and obj 54mb, so no emailing !
had to use wetransfer.
dead dog that wont lie down this is becoming.
Hi, see my edited post, save small and geometry tick boxes, also formatting and other tabs, all ok as defaults ?
also now seeing save textures, it hasnt any rasters, so untick or not bother ?
then a slider or two.
save small might allow me to attach to email, stl was 13mb so 10 being still some outmoded standard , a bit risky.
Might I suggest we have a sticky for rhino to 3D print.
Can someone make a button code and even a button, we can pop into rhino for the toolbar, that grabs all the correct settings for us., that even runs a check on the object.
artwork on it 3Dprint.
I see also the obj made a mtl file and an objbak file, so sent them all three, more confusion for anyone starting out in 3D printing.
They arenât âa non-manifold waiting to happenâ. They are intrinsically non-manifold, or in other words, their nature is non-manifold. Attempting to remove necessary non-manifold edges by exploding and joining is breaking the model.
One solution would be to redesign the model with a micro chamfer between members of the pairs of edges that come together at the non-manifold intersections, thereby preventing edges from different pairs meeting, doing away with the non-manifold issue. A chamfer an order of magnitude smaller than the filament will address the Rhino problem but not be big enough to impact the print.
HTH
Jeremy
P.S. I have no experience of 3d printing. Someone who does, may have a much simpler solution for you. Letâs hope so!
Hi,
thanks for step, I shall ask him.
He us using chitubox.
having all sorts of issues with Any Cubic, non compatabliity, then solved that, allegedly.
Anycubic old version more stable.
solved then something else happens, seems to be slicer v any cubic.
then a good thing a RERF file allows incremental exposure changes 0.4 secs for 8 files.
but then doesnt allow less, so 0.8secs looks good, but doing then 0.1secs to fine tune isnt possible.
I think the world of 3D printing needs a shake up. he has been at this 9 months now !
even got dandruff white specs over everything. in two print runs a month apart.
some webbing no doubt due to non manifold but the same design was only causing webs to occur on some bars, yet all had non manif joints.
prior sending
