Unwanted triangles

I am getting unwanted triangles on exporting STL from Sketchup to Makerbot.

I have tried to delete all unnecessary lines and to line everything up ok. I have tried to make all surfaces the correct orientation with outside consistent but cannot get rid of all triangles.

I’d be grateful for community review of my stl and further advice please.

Thank you

STL files are triangles. Read this:

Here are the files in question

Thanks but most of the triangles are where I want them (with 3D print reflecting the Sketchup image) but there are also some extraneous triangles that appear in the 3D print that are not evident in the Sketchup image on screen nor that I created.

I’m still waiting for your file.

Here are the files (I hope)…:

Not yet.

I’m not sure the upload is working…?! I see an upload percentage but then don’t see any files uploaded…?!

beamless 10 sept 17 desk to right.stl (175.4 KB)

1 Like

How about uploading the SKP file instead? It would be easier to help you if we can see where you are starting from rather than where you ended up.

I’m suffering network problems

Upload to sketchup community.skp (175.4 KB)

There are a couple of weird hidden lines. You can see those selected in the first screen shot. Even with those deleted, there are a lot of other problems to be fixed. Make the structure a group or component and use Thom Thom’s Solid Inspector2 or TIG’s Solid Solver to identify and fix.

Wow! Thank you so much! Can you advise please how you were able to visualize the hidden lines. Also how I get hold of and install the utilities you mentioned.
Much appreciated.
Dan and Alex

The hidden lines were made visible by turning on Hidden Geometry in the View menu.

Solid Inspector 2 is available from the Extension Warehouse and Solid Solver is available from the Sketchucation Extension Store.

Keep in mind that Solid Inspector can fix some of the issues with the model but you’re going to have to do a lot of the fixing manually. Take a close look at where the counter meets the wall near the tall windows/doors. There’s a gap in there that needs to be closed up.

If you draw this or another similar model, I would suggest using modeling practices that avoid the the internal geometry and stray lines from the get go. You should be able to create the entire model without ever needing to clean up internal geometry that prevents if from being a solid component/group. Doing so will speed up the entire process and reduce errors, too.

1 Like

Thanks very much Dave.

I guess problem is I don’t know what I’m doing wrong…!

I do notice that extruder tool tends to get out of alignment from primary axes…?

Do you have any tips on what to do and what not to do to avoid these flaws in future please?

Thanks again


The only reason an extrusion made with Push/Pull would be off axis is because the face being extruded is off axis.

Work in a methodical way. In the case of something like your model, draw a rectangle for the floor and give it thickness with Push/Pull before outlining the walls and cabinets. Raise the walls and cabinets as you go. Cut opening for windows and doors out of the solid walls. Watch to make sure you are drawing on axis. Pay attention to what’s happening as you draw. SketchUp will stop drawing when a closed loop of edges is completed. If it doesn’t stop drawing when you think it should, look closely at what you’ve drawn and find the gap. Don’t move on to something else until you know what you’ve just drawn is correct and clean. And practice, practice, practice.

1 Like

Many thanks for the great advice. I’ll give it a try.

Note that my SolidSolver will not fix your grouped geometry [at least in a useful way, since it deletes chucks of geometry you want!].
You need to give it a chance by doing some manually fixing - e.g. select all and intersect, cut temporary sections and delete internal faces, and so on…

Thank you for the very helpful advice.

1 Like