Weight VS cost VS easy of build questions

[ScottE]

"What is your overall size of the plywood decking with the overhangs ? Any idea how much your bare trailer weighed ?, What are you towing with a 4cyl or 6cyl Subaru?,, How does it handle towing at say 60 mph ? Really like what I'm seeing."

Overall size of my plywood platform is 9'2" X 6'4". My side walls do not sit on the plywood, they butt up to the edge and are wrapped with FG tape, giving me an internal width measurement of 6'4" (for the queen bed length.) The 5' X 8', Carry-On base trailer specs say that it weighs 375lbs. I tow with a 4cyl Subaru Forester (with a 1500lb tow rating) and it tows very well, even in pretty strong winds. I did extend the tongue by 1' and this gave me the weight/balance I was looking for (I simply unbolted the factory tongue and replaced it with a 1' longer piece of 2" X 3" rectangular tubing.)

[rustytoolss]

"What is your overall size of the plywood decking with the overhangs ? Any idea how much your bare trailer weighed ?, What are you towing with a 4cyl or 6cyl Subaru?,, How does it handle towing at say 60 mph ? Really like what I'm seeing."

Overall size of my plywood platform is 9'2" X 6'4". My side walls do not sit on the plywood, they butt up to the edge and are wrapped with FG tape, giving me an internal width measurement of 6'4" (for the queen bed length.) The 5' X 8', Carry-On base trailer specs say that it weighs 375lbs. I tow with a 4cyl Subaru Forester (with a 1500lb tow rating) and it tows very well, even in pretty strong winds. I did extend the tongue by 1' and this gave me the weight/balance I was looking for (I simply unbolted the factory tongue and replaced it with a 1' longer piece of 2" X 3" rectangular tubing.)

From what I see from the pictures of your build. All 4 walls and the roof are foam. Did you use any form for interior structure (cabinets, shelfs etc) I did not see any. Also I understand putting canvas on the outer body. But what do you do with the interior foam surfaces ? Canvas also ? I have not seen much information about interior foam surfaces (probably just have to search it more). Thanks for your help.

[GPW]

Rusty , there seems to be a reasonable size limit as far as building a pure foam trailer , without any “structural bracing" inside , walls, arches, cabinets , etc. But surprisingly foam is pretty strong by itself (skinned but without framing) when used properly ... Depending on the design , it is up to the builders good senses about whether to use a rudimentary bit of “framing” inside or not .... To err on the side of overbuilding seems normal and acceptable ...just as long as kept in the confines of reasonable weight ...

Consider this , just as a skin adds strength to the outside of the trailer , so it also does to the Inside too , increasing torsional stiffness and providing a nice finish to the walls , thinking it doesn’t have to be canvas exactly as the inner skin , but a heavy paper , old sheets , thin (non-corrugated cardboard (chipboard) , a really nice heavy decorative upholstery fabric or the same stuff you used on the outside ( or even a thin plywood paneling as a “woody” alternative )... And all that’s been thoroughly tested now by Foamie builders all across the country .... ( As all explained in the BIG Thread )

[rustytoolss]

Yeah I understand about the inner structure adding to the overall strength of the cabin. What I was asking ScottE was , from looking at his pictures. If all/most of his inner cabinet/frame work was wood (as it looks like that in the photos) or if there was also foam inner frame work.
As for the inner wall covering . I was thinking it might be possible to use something like thick wallpaper (not like grandma's house) something that looks more modern.
I have a 30ft fifth wheel. That has wallpaper type paneling in it. So why not heavy grade wallpaper. Sounds like that should work.

[rustytoolss]

Conch Fritter is a hybrid with probably a bit more on the wood side of things. However, if I can ever convince "the one who must be obeyed" to let me build a second one, I really, really want to try my hand at a foamie that has only a minor amount of wood. I can see the advantages in foam when properly done. It can be very strong, you can make almost any shape you wish, no worries on rot or rust and the weight savings is an absolute.

With all that said, most folks believe the main problem in towing is the weight. It is a concern, but the primary problem is the profile. A curved/angled front/rear is far more aerodynamic than a flat surface. A 1,500# trailer with curves both front and rear will tow better, with less power needed, than a square one. Just a function of physics.

dave

I plan to have an angled front surface.

[ScottE]

Yeah I understand about the inner structure adding to the overall strength of the cabin. What I was asking ScottE was , from looking at his pictures. If all/most of his inner cabinet/frame work was wood (as it looks like that in the photos) or if there was also foam inner frame work.
As for the inner wall covering . I was thinking it might be possible to use something like thick wallpaper (not like grandma's house) something that looks more modern.

I used 2" foam for my walls, front panel, roof, door wall, and inner bathroom wall. I used 1" foam for my closet wall, closet shelf, and kitchen shelves (inside my cabinets.) I skinned my interior walls, roof, and front and rear panels with canvas and all my interior shelves and cabinets with old bed sheet material. The sheet material is quite strong once cured (with Titebond2), and my shelves and panels are very rigid. The whole shell and inner wooden framing structure are glued together through the use of slots, Gorilla Glue, and fiberglass tape/epoxy, on all corners and edges. I believe that a fabric covering, applied with TB2 or TB3, will provide a stronger, more durable inner surface than wall paper (just my opinion.) I would suggest putting your wall paper of choice on a piece of foam and running your own tests. Who knows, it may be an effective way of skinning your interior! I ran many of my own tests on glues, materials and paints (like most other foamy builders), and I learned what worked best for me. Don't be afraid to experiment and build how you want to, this is a place to test your ideas and have fun!