pop-out front window

[Buckshott]

Hi there,


We recently purchased a Hallmark Cucherra and have found it is in need of some restoration work. Really cool camper but PO was very deceptive about issues which I failed to identify when inspecting (my bad). Gonna move forward and correct issues .
Does anyone know where I could purchase a front pass through window such as is found in the FourWheel campers? (about 16" x 20" pop-out). I see they are being used in other brands of newer campers also. I have to re-build that front wall and I think those smaller removable style windows would be an improvement as there would be more structure left surrounding the window as compared to the current (quite large) 36" slider. I've searched ebay and the web but haven't been able to locate this type of window anywhere. Any help would surely be appreciated!
Thanks!

 

[jimjxsn]

Here is a 15x24 at FactoryRVSurplus and here is a 16 3/4 x 21 1/4 at DKHardware.



You might check with the FWC factory and dealers and the ATC factory.

 

[ntsqd]

Do you need the window at all? I have little to no visibility out the rear thru our Cuchara and wish that we didn't have that window at all.

 

[Buckshott]

Here is a picture of what I'm after.
I really like the idea of being able to take a look forward up through the cab while in the camper. Also its nice to be able to throw something into or retrieve something from the cab if we want to.
I appreciate your replies!

 

[Buckshott]

Here is another one similar with a little description....

 

[Buckshott]

Bad news....
The further I went , the more dry rot I found. Its really bad. All across the rear, in the floor and up both rear sides, up front and even starting on the over-shot. It sure looked nice on the outside, but now I see that it is not really feasible to try to save it.
Feeling really, really foolish for not seeing all this when I purchased it last fall (and being suckered by the PO!). Its been sitting in my garage this winter and I just really started tearing into it a couple of weeks ago.
Gonna have to demo it.

Well...enough said about that.

Gonna move forward.

It has the upgraded one piece composite roof, so I'm thinking about starting from scratch and building a flatbed pop-up camper using the old roof.

Maybe this will evolve into a build thread.

I'm looking at foam filled honeycomb composite panels for the cabin assy., but trying to get suppliers to talk to me has not been easy,
I think they would rather not deal with DIY'ers.
I do not want any seams on the sides, so I need to locate panel material at least 15' in length.
Maybe fab up an aluminum outer frame (if I am able to go with composite panels) or "exo-skeleton". I have fabrication skills, so TIG welding would be a fun process to utilize.
Any input would be welcomed!
Cheers!

 

[Buckshott]

This is the most valuable remnant of the demo.

 

[Buckshott]

And this is a concept drawing of what we hope to build.

 

[ntsqd]

If you model the frame for aluminum and "weigh" it, and then model the frame for steel and then "weigh" that too I think that you'll find that there really isn't much weight savings in AL. The reason for this is that you're constrained to use nearly the same size tubing in both metals, but AL requires more of it to get to the same strength. I suspect that it is used by FWC, ATC, Phoenix, etc. entirely because of the corrosion aspect. AL also has a higher thermal conductance than steel, making those cold paths more effective.
There is one problem with the slightly heavier steel frame that hasn't been frequently discussed and that is your heavier wallet. Compare the cost of all of the tubes needed for the aluminum frame vs. those for the steel frame.

 

[Buckshott]

Thanks for the input...you make some good points for a steel frame. The camper would be mounted on at least a 3/4 ton flatbed pickup, so a little extra weight would be doable. The intent is for a setup that will see lots of backroads and hold up well.
If a steel frame was used, could the "skin" be bonded with Sikaflex (I believe that's what it's called) or something like it? Before or after primer?

 

[ntsqd]

As far as I know, yes it could be bonded on with Sikaflex before or after. Read up on what your bonding product of choice will bond to. I'd do so after a sealing coating of some sort, primer is porous, so I'd choose a bonding product that would adhere to whatever coating I chose. Might also look into the 3M VHB tapes as those are used to bond on the outer skins (& maybe more) of some of the really spendy diesel pusher RV's.

RV mfg's like Fleetwood don't weld the joints all the way around. They only weld on the interior to the wall surfaces. If they welded on the face surfaces they'd have to then grind every bead for the skins to lay smooth. Time is money to them.

For best R value I think a foam core construction is going to be hard to beat, but those don't deal with point loads very well. They take some thought and planning before starting.

For cabinet faces & doors I'd take a good look at Starboard.

I would also take a page from Rob Grey's Wothehellizat I/II builds and incorporate the framing for the interior features into the camper frame. Done well, more bonded (shear) panels, and the strength and rigidity of the frame will increase.

I've messed around some with designing a flat-bed camper and one design exercise that I haven't completely solved is the cold paths created by 'studs' that go from skin to skin. By using 1/2" X 1" tube for the 'studs' and offsetting them in two directions I've broken the cold path there. That forces the use of at least some 1/2" thick insulation or the cutting of notches in thicker insulation. Not sure that there is a fix for headers, footers, and around window openings. And I'm not sure if the gain is worth the added work.

One rather radical option that is worth considering is to build it entirely from wood. Build it like a boat where metal fasteners are rare rather than common. The cold paths created by the studs are not nearly as big of an issue. Weight can be quite low if well designed. The skin can be partially load bearing instead of simply a cover. If this intrigues I'll suggest finding some old copies of Wooden Boat magazine for research.

 

[Buckshott]

There is a relatively new (I think it's new) material being used by rv manufacturers as a substrate (replacing Luan) which they laminate the Filon to, it is called Azdel. They say it has some insulative properties, is impervious to moisture, and lighter & stronger than Luan.
​I don't think it would completely solve the "cold path" issue, but it may be a feasible way to minimize it? I talked with a 3M rep and they claim their (can't remember the exact name) contact cement used by rv manufacturing & repair shops will adhere to it.
Because of the point loading issue you bring up, I think I may be leaning towards a steel frame. One of my challenges will be to not "over-build" it, I am notorious for building things which end up too heavy.
Good conversation...
Thanks again!

 

[PaulT]

For cabinet faces & doors I'd take a good look at Starboard.

Starboard is used frequently on boats. There is quite a bit on my boat. There are some caveats to its use. First it is not light weight compared to wood products. Secondly, you are essentially limited to mechanical fasteners. Not many adhesives or sealants will stick to it unless there have been some advances since I looked for some a couple of years ago.

Paul

 

[Wandering Sagebrush]

Starboard is used frequently on boats. There is quite a bit on my boat. There are some caveats to its use. First it is not light weight compared to wood products. Secondly, you are essentially limited to mechanical fasteners. Not many adhesives or sealants will stick to it unless there have been some advances since I looked for some a couple of years ago.
Paul

I will reinforce what Paul said. Starboard is heavy. As it’s a slick material, even mechanical fasteners (screws) have a tendency to work loose, and it expands in sunlight/heat.

 

[ntsqd]

I knew about heavy, which is why I suggested looking at it rather than saying "it's the greatest stuff ever, use it!", but didn't know about the tendency for lag threads to work loose. Now noted.

Sounds like machine screws with nuts or thread inserts are the way to go with it. I use a lot of these at work to put threads into printed glass-filled nylon parts: https://www.mcmaster.com/92397a210