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Biggest foamies?

PostPosted: Fri Jun 26, 2020 6:48 am
by leblanda
Just a quick question!

can a 7 feet wide foamies can be built?
I plan to fiberglass it with wood interior.

Thanks

Dan

Re: Biggest foamies?

PostPosted: Fri Jun 26, 2020 8:34 am
by Pmullen503
The thing to worry about would be sag over time, which might allow water to pool on the roof unless there is a curve to the roof line. The classic teardrop shape makes the roof a lot stiffer. If your design has a large area of flat roof you can crown the roof with curved rafters. You don't need much curve and rafters don't have to be very deep. Just make sure you have a secure connection to the side walls.

Re: Biggest foamies?

PostPosted: Sat Jun 27, 2020 4:19 am
by GPW
7 feet wide may be roomy inside , but how would it be to tow ??? :thinking:

Re: Biggest foamies?

PostPosted: Sat Jun 27, 2020 11:58 am
by Postal_Dave
I think several people have taken a trailer with a 5 foot wide trailer bed, then extend the camper over the wheel wells. That's close to 7 foot wide.

Re: Biggest foamies?

PostPosted: Sun Jun 28, 2020 6:04 am
by RJ Howell
The roof will be the biggest challenage!
My roof is 77" x 120" with a slight arc (3" in the 120"). My roof is not traditional as it lifts. So, yes it can be done.

Image

Re: Biggest foamies?

PostPosted: Sun Jun 28, 2020 2:57 pm
by OP827
My roof is 6'7" wide and 15' long and it is a fibreglassed 1.5" XPS foam with a few stiffeners across the roof. I would not leave it outside under a heavy snow load though. And this one tows great on highway speeds, much better than 15' fibreglass "Boler" trailer I used to have.

Re: Biggest foamies?

PostPosted: Mon Jun 29, 2020 10:57 am
by rjgimp
I have a 7' x 14' popup camper I am intending to strip to the frame for a foamie build. My impression based on what I have seen and read here over the past couple years is that a foamie can be built to virtually any size that one can legally drag down the road. I believe they are stronger in many respects than traditionally built campers.

Re: Biggest foamies?

PostPosted: Mon Jun 29, 2020 11:41 am
by dogcatcher
With planning and some "engineered" beam supports using lumber and plywood construction, the sagging problem would be eliminated. Ply and lumber beams are amazingly strong, and can be constructed pretty easily in a home shop.

Re: Biggest foamies?

PostPosted: Sun Aug 02, 2020 11:18 am
by dbhosttexas
leblanda wrote:Just a quick question!

can a 7 feet wide foamies can be built?
I plan to fiberglass it with wood interior.

Thanks

Dan


Dan,

My camper / truck cap build is aiming for just at 7' wide. I will require towing mirrors I know that, My overall length of the cap / camper will be, considering I am planning an overcab, not a sleeper, but storage compartment, at just over 8'. There will be an overall curve to the roof, but it will be very slight, after the curve of the nose of the cap of course, but once we go to mostly flat, we will be making a 1" curve over the remaining 6.5 feet.

My plan is to grid the roof with 3/4" ply structural members, that are fully glassed in. I am still researching foam / fiberglass techniques, or more correctly digging up prior research, but I am planning on using fiberglass with a compatible resin over foam instead of PMF.

Re: Biggest foamies?

PostPosted: Sun Aug 02, 2020 1:33 pm
by tony.latham
...but I am planning on using fiberglass with a compatible resin over foam instead of PMF.


Epoxy is compatible with all types of foam board.

Tony

Re: Biggest foamies?

PostPosted: Mon Aug 03, 2020 5:32 am
by GPW
What about all the Sanding ??? The real question is what type of finish are you going for ??? :thinking: Fiberglass is a Lot of work !!! :o

Re: Biggest foamies?

PostPosted: Mon Aug 03, 2020 6:21 am
by RJ Howell
RJ Howell wrote:The roof will be the biggest challenage!
My roof is 77" x 120" with a slight arc (3" in the 120"). My roof is not traditional as it lifts. So, yes it can be done.

Image


I Edited the width.. 6'-5" not 65"

Re: Biggest foamies?

PostPosted: Mon Aug 03, 2020 7:31 am
by tony.latham
Fiberglass is a Lot of work !!! :o


I fiberglassed my last teardop. I didn't keep track of the time. But here's my best guess:

Glassing the walls: 1 hour each.

Image

Glassing the roof: 1.5 hours



Hatch: 1 hour

Sanding all surfaces with a random orbital sander and 120 grit sandpaper to take the sheen off: 1.5 hours.

Adding spot filler over primer and final sanding: 3 hours

Image

Obvioulsly, this is over wood --not foam. But I don't think nine hours is a lotta work. Not for a teardrop that took me three months. And those estimates are conservative. It probably took less time.

:thinking:

I would hope that RJ would chime in on this subject for a second opinion.

Tony

Re: Biggest foamies?

PostPosted: Tue Aug 04, 2020 4:57 am
by GPW
Best ask KCS about fiberglass over FOAM …

Re: Biggest foamies?

PostPosted: Wed Aug 05, 2020 5:08 pm
by OP827
Epoxy over foam can be quite a bit more body work if you are aiming for close to automotive finish. But if not, then it is not much work, in fact could be easier to lay down than with PMF with canvas. Epoxy is 100% solids, so less coats needed, a maximum 3 before you get to a glass like surface. This is only my build experience and I do not have PMF experience, except for my own testing samples before I selected to go epoxy path.