Hello. I’ve just created a thing with SketchUp Make 2015 that I want to print with a 3d printer. It’s my first object created with Sketchup. I’ve exported it in .stl extension with a plugin, but when I try to get a print preview (with slic3r) I obtain a cut object as if some of the parts aren’t filled.
To make me explain better, this is the print preview with slicer:
How can I solve?
Thanks
Please upload your sketchup model and someone will help.
Ok, here’s the project.
Macchina arduino bluetooth2.stl (994.0 KB)
The model must be a SketchUp Solid
See…
Understanding Solid Objects in SketchUp — Aidan Chopra
To begin fixing your model, delete the unnecessary interior faces shown here in red.
Thaks a lot 
Good news, i found other useless faces and here’s the result:
Macchina arduino bluetooth NUOVO4.stl (946.2 KB)
It seens good but slic3r found some errors that I can’t see. How could I solve these erros?
The sketchup file is:
Download skp file
Now that you understand the concept of a Solid, here’s a handy tool for sorting out stubborn problems.
Solid Inspector² — Extension Warehouse
It’s useful not only for finding errors, but also for learning how to avoid them in the future.
The more proficient you become with SU, the less you will need such things.
The CleanUp3 plugin is my ‘go to’ plugin for cleaning out models of those pesky useless artifacts. It will find and delete leftover line segments, and there are settings for closing holes that have close edges (user setting for tolerance). I also run a final check by running the model through Netfabb Basic prior to slicing.
I just downloaded Cleanup3. It seems like a great program but how did you remove interior faces with this? Doesn’t it just erase stray edges? Don’t we still have to manually erase interior faces or is there a way to autodelete them?
Rick there are many plugins to clean up, but you need to understand what they are ‘cleaning’.
Quite often I use a "solid’ plugin and it gives me an ambiguous answer, I understand the underlying geometry so I can find the actual problem.
Learn the roots of the software and use plugins to automate things you already know how to do.
Yes, I understand. I can see the interior faces but they are made up of different angles and in tight spaces and all in a radial array of 12 units. If anything, it’s a lesson for me to make the component cleaner on the insides before I radial array and explode the model for cleaning up.
But I read today about the tactic that Dave also showed me which is that I can take my currently exploded model, make it a component, and then blow up a copy of it 100 times. This might make it easier to pick all of the interior faces and delete them manually. I will try that for now, and then just try to never have complicated inner faces of my components before I radial array them.
Instead of trying to erase the whole unwanted interior face, try erase one line of the face. That will make the remaining lines of that face “stray edges”, which Clean-up will take care of removing for you.
There are errors solid inspector cannot fix, but TIG’s solid solver found a number of coplanar edges and after correction the skp is now reporting solid. IHMO it is great to have a program to flag errors, but with the number of edges asking folks to do that manually seems questionable in my mind especially with the number of programs that will solve on batch basis. On top of that then to properly 3d print there usually wants be added an internal shell so it deleting internal geo is just a fraction of the solution.
Hmac1AA.skp (256.0 KB) ere is the solid skp file but suggest you run it throught the free version of Netfabb as noted above to just get confirmation of its " solidness".
Here is the stl file mac1AA.stl (911.0 KB)
Depending on the print technology you are using some other mods may be necessary see the materialize info in the 3d ware house to help you.
I just found a free program called meshmixer that appears very powerful to help you get model in shape to print. It is not a plugin but program.
BTW the " mounting" lugs on the bottom are too thin, because of the top and bottom protrusions, depending on print technology you select, the item will have to be installed on edge or angle on the print platen which means some support post will be required 
.
OMG, I love that idea.
thank you so much!
Not my idea. The need for support has been factored into prints before. How installed on platen may not remove need for supports just reduce the number needed in the model.Some models you cannot avoid but IMHO if possible you probably want to avoid. It depends on the type of print technologly used . Here is a nice summary The Free Beginner's Guide - 3D Printing Industry.