Curving aluminum framing?

[dbhosttexas]

Okay I am not sure I'm posting in the right place, but here I am...

Still working on designing the camper, and honing my skills before doing the build, and I am running into a head scratcher.

So my intention is to build a foamie around an aluminum frame, considering using 1.5"x1.5" L channel in some of the lower stress areas,

I want to make a curved face to the overcab area, and the overcab is going to be 100% for storage. I will be making a short kig fold up across the bed of the truck.

Anyway, To the technique question...

How do I bend the L channel? I assume kerf, kerf, kerf, kerf, bend... weld... Repeat the process with the foam, of course excluding the weld part...

This brings the question up that how do I smoothe the segments so it doesn't look like a ton of flat spots instead of one smooth curve?

[QueticoBill]

If talking about long large arcs of channel, angle, and tube, there are machines that do it. https://www.hossfeldbender.com/ is what I have used, but there are a lot. I saw Harbor Freight gad one. Im sure more out there.

[twisted lines]

How do I bend the L channel? I assume kerf, kerf, kerf, kerf, bend... weld... Repeat the process with the foam, of course excluding the weld part...

This brings the question up that how do I smooth the segments so it doesn't look like a ton of flat spots instead of one smooth curve?

I rolled my Channel [

L Angle can be rolled as well its not easy & cheap, 1" L Angle or square would be much easier and cheaper as well as the foam.

If I do a more foamy soon, I hope to find 1/2" foam & Bend it in layers without kerfing?

[QueticoBill]

I've thought about that foam idea. Here, 1/2" is $15, 1" $20, and 1 1/2" $25. Plus adhesive. Not a overwhelming cost but adds up. Do you think glueing up three layers saves time over kerfing?

[twisted lines]

I glued and sanded my kurfs, Inside I didn't like it, the back to back kerf is a great Idea that needs remembered.
I couldn't find 1/2 or 3/4 without traveling

Thanks G.

[dbhosttexas]

Well, my thought process on the design, and mind you it might be massively stupid, but here goes.

R value, isn't immense, but should be about R8 for 1.5", maybe a little less, but certainly way more than the truck bed metal plus the bedrug, and various weatherstripping.

So yes, I was planning on affixing 1.5" XPS foam to the 1.5" L channel using n interlocking rabbet type joint at the corners. I hope...

Once the XPS is bonded to the frame, with I am assuming Liquid Nails or something similar, I will get started with the most likely PMF. I think I can be happy with PMF as long as I figure out how to smooth it so I can get at least a passable finish with it.

Interior ceiling, and walls will have cedar veneer laminated, and oiled. And yes I am aiming for aromatic cedar for its insect repellent qualities.

I need to rig up a bed system that will be an effectively short king. 75" x 76", with the 76" going transverse across the truck, so the cap has to clear that inside, thus the wide cap. I want it to scissor into basically 2 troop carrier type couches when set up in day mode, and have the cap extend al the way to the end of the open tailgate allowing me that additional 22" + 7" floor space to allow me a place to actually put feet down on a floor before getting out of the bed...

So yes, I am having issues coming up with a suitable design that I can actually implement. Mostly due to my spotty skills at best...

I am trying to avoid wood framing due to concerns for strength and rot. And while steel would be considerably easier to work with, it would also make the entire camper considerably heavier. I am trying to work within the limits of a half ton truck...

[pchast]

Consider looking into using either latex caulking or lightweight spackle
mixed into latex paint and applied with a squeegie. This only after a
coat of primer.

Please experiment to prove it.

[twisted lines]

Shrinker / Stretchers will work up to 16 Gauge Aluminum, if you could find that thin Angle They could do it!

Wood works well if sealed with the Mix. & King

I glued 2" of foam in my aluminum walls with Gorilla glue, Expands like crazy & worked well for me!

[dbhosttexas]

Shrinker / Stretchers will work up to 16 Gauge Aluminum, if you could find that thin Angle They could do it!

Wood works well if sealed with the Mix. & King

I glued 2" of foam in my aluminum walls with Gorilla glue, Expands like crazy & worked well for me!

Wood would certainly be tremendously easier to work with. I am VERY leery of using it from the rot stories I have seen on wood framed campers. How could I seal it properly?

Honestly if it weren't for my wifes insisting on a king bed instead of a queen, I would just go to Craigslist, and wait until a hi top fiberglass shell like a Leer came up used, and then make one of those extender box things to hold the AC unit and provide a door. The drawback of a 6.5 foot bed truck!

[twisted lines]

The folks here call it the mix ?

Thinned wood sealer so it soaks in then evaporates till it won’t soak anymore,
Ratio of thinner’s, reducers, changes from 50/50 ? To 25/75? several coats.
They don’t Take the time on the line, that takes hours to build a RV.
Hope for more from someone who knows!

[GPW]

Bending Aluminum ? … anneal it …

[QueticoBill]

I think annealing is not a good option if using it for a frame.

[GPW]

Just the curved parts ….

[CRZ42]

I was taught to use soot from an acetylene flame and when that starts to burn off the aluminum is the right temp to bend which is similar to the sharpie method the sharpie method on youtube.
If it were me i would build a radius or two out of ply to clamp the stock to so it can cool in position. It may take a few cycles to get the bend right as the metal will have some memory and spring back. Plus you'll be able to easily duplicate your bends.
the aluminum will lose about half the strength that it had preheating, but will retrain likely retain the same strength as knerfing and welding it.