DIY Composite Flatbed Camper Build

[Terra Ops]

I have the Propex heater in my current camper and it works great. With this next build having over 900 ah of lithium, I was looking for alternatives to fuel type heaters that produce dry heat like the diesel, gas, and propane. Not interested in radiant for various reasons. If I do end up with a fuel type, I thought I'd go with Lavaner diesel heater. I was considering Autoterm until a builder friend told me he had tried many various brands including the Autoterm and found Lavaner to be good.
This is a flatbed build. Same truck that I've had other campers on in the past. It is aluminum by https://www.blueridgemfg.com/ . Truck is a 2014 Ram 2500 diesel.

 

[simple]

Looks like you have a short box truck and from the camper drawing it appears you're doing a 7ft flatbed and 10ft cabin.

Regarding the door location, what are your thoughts on sheer and stress at the inside corner where the nose meets the cabin?

Also are you adding any internal framing or extra considerations for the length of the nose?

Do you plan to tow with this setup? If so, what are your thoughts on extensions and clearances?

 

[DzlToy]

Ninety-degree corners are high stress points and ripe for crack-propagation. Look at an FEA model, almost any one will do. Unless your 90-degree joints are massively over-built, which adds weight and cost, you would be better off using a chamfered or supported corner of some kind. In the marine world, 90-degree joins are filled with "fillets" of thickened epoxy.

 

[Terra Ops]

Looks like you have a short box truck and from the camper drawing it appears you're doing a 7ft flatbed and 10ft cabin.

Regarding the door location, what are your thoughts on sheer and stress at the inside corner where the nose meets the cabin?

Also are you adding any internal framing or extra considerations for the length of the nose?

Do you plan to tow with this setup? If so, what are your thoughts on extensions and clearances?

I think the box was originally 6.5', and the flat bed extends to edge of hitch for 7 ft.
Door placement and cabover length are definitely considerations. Thats one thing I appreciate working with CPT. Their engineers helped guide me with what I wanted to do. There is internal framing nicknamed the flag that anchors the cabover to the main box. Door location is far enough from corner for non-issue. The design of the door also lends to structural support as well.
As for towing, I have never had a need or desire when traveling with the camper. The rear extends 2.5', so I think you could pull a trailer, just depends on the type.

 

[simple]

Do you know what CPT's warranty is on a custom design if there is a mechanical failure?

 

[NOPEC]

I have the Propex heater in my current camper and it works great. With this next build having over 900 ah of lithium, I was looking for alternatives to fuel type heaters that produce dry heat like the diesel, gas, and propane. Not interested in radiant for various reasons. If I do end up with a fuel type, I thought I'd go with Lavaner diesel heater. I was considering Autoterm until a builder friend told me he had tried many various brands including the Autoterm and found Lavaner to be good.
This is a flatbed build. Same truck that I've had other campers on in the past. It is aluminum by https://www.blueridgemfg.com/ . Truck is a 2014 Ram 2500 diesel.

Another vote for Propex, mine has been flawless. On my new CPT 8 ft. slide in, I am going with an external version of the smaller Propex (HS2211) which will live on the exterior vertical wall of the camper, inside the truck box. Not loving the two 60mm holes for the hot/cold air but definitely I am loving the extra interior space which I can use for stuff I don't need....

 

[simple]

Another vote for Propex, mine has been flawless. On my new CPT 8 ft. slide in, I am going with an external version of the smaller Propex (HS2211) which will live on the exterior vertical wall of the camper, inside the truck box. Not loving the two 60mm holes for the hot/cold air but definitely I am loving the extra interior space which I can use for stuff I don't need....

That's a cool idea. I bet the holes wont be bad if they route through the middle of a side panel. Where are you thinking of housing the propane tank?

 

[NOPEC]

That's a cool idea. I bet the holes wont be bad if they route through the middle of a side panel. Where are you thinking of housing the propane tank?

Simple/Terra Ops
The holes will be fine and yes, mid panel as you suggest. I will limit the run length of the hoses and will also use short molded silcone 90 degree angles to bring the hose end into the cabin. The Propex "Slinky like" 60mm hose is pretty tough (especially the exterior version) and does bend fairly well but the hard 90s I think will work well. They will also be really cool but sadly, no one will ever see them... The fittings I am using are what you would find used on engines where heat and vibration are an issue such as connecting turbos to pipe, etc.

I am using a dedicated 20 lb propane bottle within a sealed/vented interior locker, on the floor, forward passenger side.

 

[Terra Ops]

Do you know what CPT's warranty is on a custom design if there is a mechanical failure?

CPT has a one-year warranty.
In general, they warranty the materials, and workmanship of the products that they produce.
They cannot offer a mechanical warranty as they cannot control how the unit is being used.

 

[Terra Ops]

Simple/Terra Ops
The holes will be fine and yes, mid panel as you suggest. I will limit the run length of the hoses and will also use short molded silcone 90 degree angles to bring the hose end into the cabin. The Propex "Slinky like" 60mm hose is pretty tough (especially the exterior version) and does bend fairly well but the hard 90s I think will work well. They will also be really cool but sadly, no one will ever see them... The fittings I am using are what you would find used on engines where heat and vibration are an issue such as connecting turbos to pipe, etc.

I am using a dedicated 20 lb propane bottle within a sealed/vented interior locker, on the floor, forward passenger side.

I was hoping to get away from a fuel base heat, but it may be a good back up. While I've been happy with the propex, the propane tank is heavy and takes space. Scout does something similar to what you are describing with diesel heater. Wish I could find one of these: