3d Printing Setup Check

Attached is a model of a single pontoon, which eventually will be part of a catamaran. I plan to 3D print this and use it with RC, so it needs to be solid & print correctly. I would appreciate it if someone would confirm that I am on the right track before I continue to far. Here is what I did.

Made a pontoon and it passed solid inspector; made it a group
Copied it in place
Scaled it down from all sides by 3/16" which is the wall thickness I want.
Reversed the faces of the interior pontoon
Made both the inside and outside pontoon faces a component

Now solid inspector gives me 2 nested instances. I understand one is the inside pontoon. Is the other that the inside pontoon is a group? Should I have exploded the groups (inside and outside pontoons) before making it a component?
Final Cat.skp (693.4 KB)

What I have now is a pontoon that has a 3/16" wall that should print. Right?

As I am definitely learning, any advice would be greatly appreciated. Thanks in advance.

I would explode the ponton component and the group inside Component #1. Leave Component #1 as the solid.

I expect you’ll need to add some internal supports before printing.

The first thing to understand is that in SketchUp a “solid” is a single group or component instance. You do not want or need nested groups. You should explode both groups, select all, and then make a single group.

The second thing is that the back sides of the faces in the surfaces must be oriented toward where ths print material will go. So the interior shell should have its front sides facing toward the air in the middle of the pontoon and the outer surface should have front sides toward the exterior air

Any suggestions on internal supports? Bulkhead style? Bars? 2-3 or 6-8?

I guess it depends on the printer and material and how you’re feeling. Personally I think I would do bulkheads.

Unless there is a reason to have it hollow, let the printer software provide the supports. Otherwise, bulkheads would be one choice. Another consideration is the hull thickness and the stresses it may see.