Whats happening with this model upload to shapeways?


#1

Hi all - I would appreciate any help or feedback. I am modeling a belt buckle in Make 2015 and exporting it as a stl file to 3D print on Shapeways and after several successful uploads Shapeways is dropping out a detail off the model. I’ve uploaded a jpg with three screenshots in one image - one of the current model that i’ve uploaded and two of the shapeways site with a pevious model rendering correctly and the current model rendering without the recessed spaces. Any ideas what’s going on?

Maybe there is no way to help with only this information?

Thanks,
Ben


#2

It would be easier to tell if you could share the SKP file.


#3

It’s almost certainly not a “manifold solid”.
Please upload the SKP and we can see what you need to do to fix it.
It doesn’t look that complex, so hopefully it’ll be easy to sort out…


#4

belt buckle spot2015.skp (652.0 KB)

Thanks all, here is the model.


#5

Hi TIG, I uploaded the model of my belt buckle, would appreciate if you might have a chance to take a look and see if you can see why the recesses are dropping out.

Thanks,
Ben


#6

HI Dave, I uploaded the model of my belt buckle and if you have a chance to take a look i’d appreciate it!

Thanks,
Ben


#7

I continued to work the model and got it to work. there were some planes that were not intersected well, which often are not a problem, but these seemed to be.


#8

you have won the bet…

@spot2014: If you’re going to 3D print something, you should never ignore such problems and make a clean and solid model.


#9

Cotty has shown you what’s wrong and there’s quite a bit. I think it would be easier to start from scratch than to fix the one you’ve got.


#10

The front view looked fairly straightforward to fix…
BUT the back has several nested groups etc, making it non-solid.
These need exploding.
Then they’ll intersect the remaining volumes, making it non-solid again.
There’s a lot to fix.
Also you have modeled it at a small [real] size - SketchUp cannot cope with creating edges <1/1000" long as it sees both ends as coincident, then reliant faces are also missed.
Model it say x10 bigger and rescale down to the desire size at the very end.
Small geometry can exist, but it cannot be created.

To recap on solidity…
A ‘manifold solid’ is a group or component-instance which contains only ‘geometry’ [edges and faces].
This means there can be no nested groups of component-instances, or other non-geometry entities, inside the ‘container’.
Also every edge must support exactly two faces - no fewer and no more.
So, no faceless-edges, no edges forming a perimeter to a hole in a surface or a ‘shelf/flap/ledge’ form, no internal-partition faces [which will have three or more faces], no otherwise seemingly solid volumes sharing an edge [e.g. two cubes with one common edge - where that edge has four faces].
Also note how all faces should be oriented ‘outwards’ - you should see no back-face materials when viewing in Monochrome mode - usually blue-gray [depending on the Style] - the front face material is usually off-white.
The context-menu can be used to ‘reverse’ badly oriented selected faces [i.e. it flips them over so the back/fronts swap], but if the object is a true solid then the context-menu ‘orient’ option with one selected face that is already properly oriented will orient all connected geometry appropriately to match.
Also note that if the container’s Entity Info says “Solid”, then it probably is 3d-printable - BUT it is possible to make a form that reports as solid which cannot exist in the real world - typically this has geometry which loops back into itself, but does not intersect with any faces through which it passes, like magician passing his arm through an imperforate brick-wall - in reality it’d be impossible.
To check for this… select all of the ‘Solid’ object’s geometry [inside an Edit] and use context-menu > Intersect > with Context…
Now if you leave the Edit mode and Entity Info still says it’s still a ‘Solid’ then it really is ! But if it no longer reports that then parts of the geometry have now intersected and make things like partition-faces which preclude solidity.

To fix the various issues which lead to non-Solid reports you need to Edit the container, explode any nested entities, and delete the unwanted internal faces, or flaps; also heal holes by overdrawing edges to complete the faces etc.
Using X-ray mode and temporary section cuts will assist in seeing what needs doing.

Thomthom’s Solid-Inspector shows issues.
His Solid-Inspector2 attempts to fix them.
My own SolidSolver also tries to fix issues - including self-intersecting volumes and the common issues like holes and internal faces…

However, no algorithms can beat your eyes and brains in fixing your own solids - it’s easy to make a form that is un-fixable using a plugin…
Save those for fixing the few issues you can’t fathom, after you have manually done all you can - the potential solutions increase exponentially as you add more errors…


#11

Thanks TIG, your comments are very helpful - others comments (“you should never ignore such problems and make a clean and solid model”) are not - as if my intention was to make an dirty model! Also, there are time i can “ignore” such problems because I am not building the space shuttle and shapways prints the model just fine.

The problems are not all mine - sketchup is not flawless. It often reverses face on it’s own, fails to intersect geometry when directed. It can be VERY frustrating. Why you cannot control tolerances, or dimensioning (like autoCAD) is strange, why you cannot draw a sphere directly is frustrating, why you can draw any shape relative to a line that is not in the x,y,z plane is frustrating, and why they have not adjusted the program to work on hi res screens is stupid, and it often will not heal holes by overdrawing edges. Other than these and many other issues, the program is great and I love it. I’m and architect and use if mostly for that, and at that scale it works pretty well.

The most helpful comment that I did not realize is that I should scale up the whole thing to build it and then scale it back down! It is difficult to work on it when it is this small and I wondered if this was the issue (though - is should be easy to set the program up so that scale does not matter)

I intentionally leave things in groups because I want to be able to move them easily later. shapeways often does not recognize the groups and prints them fine.


#12

Sorry that you misunderstood my intention, since there are some likes for my post, it can’t be a totally wrong suggestion?! Maybe the error corrections from 3D printing services getting better and are able to ignore/reapair errors of uploaded models, but if you wish to be on the safe side, you should prepare the model as a solid model…


#13

I looked at your model and couldn’t bring myself to begin to explain the problems with it. Just because shapeways’ software somehow manages to decipher your intent wont help if you want to model something and print it yourself.
Personally I have no problem controlling my tolerances or dimensions… drawing lines off axis…

Blaming sketchup for your issues means you haven’t learnt to use it.

Here have a sphere.


#14

Cotty, I’m not trying to be argumentative - and I appreciate good feedback, but i did not misunderstand your comment. Whats to misunderstand? telling me to build a better model is not helpful. OBVIOUSLY i want to build a better model - it’s why i came to the forum! So often I find on forums that “experts” like yourself get somewhat offended by the non-expert and just can’t help themselves from pointing out the novices stupidity. That’s what you did. Everyone who liked your post are experts in sketchup themselves and are happy that you told me to do a better job. And! you had to state again in your response that I should “prepare the model as a solid” as if I didn’t try to do that in the first place.


#15

just another “expert” who likes to belittle the novice. i just wanted help with my model - not people pointing out that i’m an idiot. Sketchup does cause problems that are difficult to fix and are non-intuituve. the only reason you know how to fix them is because you had them happen as well and you learned how to fix them or avoid them in the first place. that does not mean they don’t happen. There are entire blogs dedicated to the issue of why it’s so difficult to draw off axis. I don’t care if it’s easy for you - doesn’t help me.


#16

There are several comments from you which show me that your intention wasn’t to create a solid, why should I explain the process to you in this case? e.g.

And I never wrote that you should create a better model, I only recommended to create a solid model. If you don’t know what a solid model is, you can ask for more details or read through @TIG’s nice explanation (he’s an expert too).


#17

I’m new to sketchup and 3d printing as well and found this kick ass webpage that completely tells you how to prepare models for 3d printing in sketchup.

This should be a sticky I think.

http://reprap.org/wiki/Sketchup_Modeling_for_3d_Printing


#18

Thanks Rick, I appreciate the link!


#19

You are welcome.

Its the best single page that helps you properly make printable models.