Thank you TIG.
I didn't notice any highlights of the offending geometry.
Is there any other tool that can find the offending intersected geometry?
I'd like to know how it actually happened to being with, for future reference...
Anyway, thanks again for concisely explaining how to fix the issue.

p.s., I still get SketchUp Bug Splat if I put two of the same component in model. Does not happen if there are two different components, i.e., Main Rib Center & Outboard Center Rib.
I sent a Bug Splat report, Crash Report #73801. No response yet...

I created the components from the same source and made minor changes.
One has two ‘flats’, the other one ‘flat’.
I run Solid Inspector2 on both and they come up ‘No errors, shiny”
Running SolidSolver on Main Center Rib comes up ‘The Selected GROUP/INSTANCE is already a 'Solid' !’
Main Rib Center.skp

Running SolidSolver the Outboard Main Rib ‘This seemingly 'Solid' Selected GROUP/INSTANCE 'intersects' itself !’. SolidSolver then removes everything except the guide points...
Outboard Main Rib.skp

I’ve spent hours trying to find anything wrong…
Although the Entity info says it is a Solid Component in the model (and the exported .stl prints on the 3D printer) it is just bugging me!
Also, Sketchup will BugSplat! if I check and there are multiple components in the model.

What am I missing?

@dave r said:

...I used Curviloft ...

Thanks, I'll look at it and see if I can clean up my model.

@pilou said:

Maybe this can interest you!
TaffGosh the SketchUp Master of domes!

Verrrrry interesting... Thank you for the lead... lots of great information.

@dave r said:

... Maybe you need a coyote trap.

Trying to trap is problematic... don't want to draw them onto your land... a donkey will keep them away or kill them... then they stay away.

Your model of the strut is awesome... hope to be able to do modeling like you some day.
Especially like the way you were able to get the 'flat' really flat.

@dave r said:

Would this be close to what you're trying to achieve?...

eh.. pretty darn close... I just need to adjust the angle of the flat to the 'hub' angles for the dome struts, i.e., V1, V2, V3, etc...

That pic is much cleaner then what I have so far:

Trying to document the dome I've built... planned use to cover round bale hay and provide pasture shelters for goats and donkey's... yup got two (mother and daughter) to keep coyotes away... coyotes killed one of my goats and the neighbors cow

Anyway, here is the dome I built so far... need to make the skin.

@gilles said:

Fine, scaling up to X100 and processing a hole works fine and gives a solid.

I tried with VisuHole and it still did not work... could you give more detail? i.e., 'processing a hole'...

SolidSolver still gave 'nested groups' and would not fix...

I created circle, selected all, Scaled factor 100, opened VisuHole, selected stencil, applied at guide...

Edit: I did it over again and this time it worked... SolidSolver still found 'nested group' but fixed it

Thanks so much for your input...

@gilles said:

It may be tiny surface issue so scale up the model to X100 or X1000 before perform such operations, and post your model in SU 2015 version please.

I'll give it a whirl... here is 2015 version:
Make Hole in Flat (2015).skp

@moot said:

... I'm trying to get a hole through the flat... struggling... Can make the hole, but lose the 'solid'...

Well, I'm stumped... tried VisuHole. It made the hole all the way through the model but SolidSolver says there is 'nested group', tries to fix it - but can't...

Here's a pic with the guides for (3/16 radius) hole I want...

Make Hole in Flat.skp

@pilou said:

You must move points/segments of the inner together !
And make many more sections on each parts!
Your cylinder can't bend without more sections

Thanks... works great using FredoScale!

Now, just one more thing... I'm trying to get a hole through the flat... struggling, but I'm going to try to figure it out... Can make the hole, but lose the 'solid'... going to spend some time on it before I ask for help

Thank you sdmitch. I've got part of what I want now...
Now I'm trying to bend the flat section...

The Flat is a solid... problem is, when I get the 30 degree bend I can't make it solid... something I'm missing/doing wrong? I figure it has something to do with the curved surface intersecting the tube angle... but I can't seem to get rid of the extra edges/faces that are causing the model to keep from becoming a 'solid'

Strut.skp

I'm trying to figure out how to flatten a pipe/cylinder...

I imported a graphic on what I would like to model, here's my .skp:

Strut.skp

I am admin. Seems like after making a change in my Preferences, Files, Models file path, it started working... just needed a 'tickle'?

Make 2016 lists files (8) I've opened, most resent at top.
I'm looking at 2017 and the file list is filled (8) but when I open another file the list does not update and the most recent is not listed.
Anyone know what's up with that? I've researched and see that there are other posting about MRU list problems in SketchUp (way back)... but no answers... very aggravating to have to keep going to file open to get files, especially when working on multiple files for a project.

Also, I'd like to be able to clear the list when starting a new project...

Thanks for the response... I've searched for export STEP (STP), PARASOLID, and IGES with no results... found import plug-ins/extensions but nothing to export... or convert... must be in all the wrong places

Is there any way to convert (or export via plug-in) from .skp or .stl to STEP (STP), PARASOLID, or an IGES file format?

I don't know how I can thank Dave R enough for giving clear, concise, and understandable information. Dave R is THE MASTER

@pilou said:

You can make the same things than the Pro with the SU Make version...
except the fact that you must choose by hand that you must erase for have the volume resulting wishing!
Intersection, Union, Difference, Cut, Divide !

Only external skin is possible!

Thanks pilou...

I think I have made some progress in understanding the 'intersection' stuff... I was able to 'subtract' the part of the vertical core (that fits over the horizontal core, i.e., like a saddle), manually closed it up and now Solid. I set the to cores together and used SolidSolver... it fixed some things and now the 2 cores are a solid group.

@dave r said:

Moot: I can show you "live" how I did it but it'll have to wait until I get home from work this afternoon.

That will work for me... whenever it is convenient for you... send me PM with approx. time so I am sure to be on the lookout.

@dave r said:

Good luck with the coyotes and the goats. On average, how many eggs do your goats lay daily?

I do find eggs in the goat shed... not sure whose they are

yes, affirmative!
I'm still trying to figure it out... I've got the cores separated as solids and am following the directions (from SketchUp https://help.sketchup.com/en/article/3000100, Subtracting one solid from another (or use Intersect Faces with Model) section). Is that the procedure I should be using? or should I be using Trimming one solid with another section? Problem with the Trimming is that I don't have Pro.

Well, I thought I almost had it... subtracted the horizontal core from the vertical core where they intersected, manually patched up the 'open faces'... BugSplat!

I'm taking a break now... go see if the Coyotes are still prowling around the goat shed... pick some eggs... see if I can clear my head...

Just saw your post pilou... thanks

yes sir... you make it look so easy I really feel dumb...
There is the one complete hole (where the casing metal is poured) and the angled core is partially open at the top . The opening at the top of the angled core is to allow venting. There will be a 'funnel' above the main core to 'push' the molten metal.
I've been trying to get the core into a solid but... anyway... as it was, it did print...
sooo, how the heck did you do it? and where should I start to get similar results??