Dynarawr/Dynasoar: Fiberglass PVC Foamie Truck Expedition Camper

calling RxComposite & Fallguy!

Greetings from a mostly landlubber, although I did race with the Rutgers sailing team in grad school but it’s hardly mentionable!

Long, long lurker. I haven't and still don't have anything worthwhile to contribute, hence the silence. Here's my project however and I am graciously open to any and all help with all points of my proposed design and construction. I especially need assistance with selecting and determining my laminate and epoxy schedule.

Background:
This is to be a very small expedition/overland/camper lifting roof box for our family of five: two european sized adults and 3 kids under the age of five. We need to all be able to eat and sleep inside, with the proviso that the current 1.5yr, 3yr and 5yr olds all still have room to sleep in 6 years. Box to be 1.9m x 2.4m x 1.5m/2.125m (roof down and up heights).

We are headed to Senegal first with the truck. I've got 4 weeks beginning next week to build out as much as I can of this box before it ships with my household. I will be paying $$$ for any/all weight in it or with it. It HAS to be light because my Toyota Dyna 4x4 is HEAVY and because shipping costs are insane. After it gets to West Africa I'll mount it on the truck and never have to separate or pay to ship them again but it needs to make it that far first. Accordingly, I will need to make a plywood shipping box to go around it at the end of week 4. I'm off work for these 4 weeks bar about 1 hr a day of job maintenance stuff. Oh yeah, I also have to pack and supply my family for 3 years during that time so we're still plenty busy.

After Senegal, our next stop is somewhere like Bangkok, Frankfurt, Sao Paulo, Casablanca, Pretoria... you get the idea. With my job I could be going to any number of varied different places. For this reason the camper needs to be truly 4-season capable even if that's not entirely necessary to begin with in Dakar.

Materials:
E-Glass
Epoxy with high(er) elongation to match foam
PVC foam, 60/80 density from Carboncore, possibly some Gurit 80 if I can swallow two 24-hour long drives in opposite directions.

Money:
Total budget target for the shell build (see last image) is $5,000 including fuel/transportation costs. I do have a van that can hold 3' vertical stacked feet of 4'x8' material so I will be driving to source materials. All trips begin from DE/NJ border and/or Poconos, PA.


Plans:
Intent is to infuse panels. I can handle building a table big enough for the largest two panels (1.9m x 2.4m). With my relative inexperience this method doesn't seem harder or worse than a wet layup and bag mess and at least will produce nice flat panels with minimal extra weight or thicknesses when I get it right. I'm planning for the material waste as well as the waste of learning curve production failures. Unless someone can convince me to do the whole thing wet and sand forever [I'm malleable and willing to listen to experience here!].

Roof will be raised with electric linear actuators. I’ve got experience with these and will probably be using units with 500# static capacity, one in each corner. The motor for these will be 24v, but can also be run from outside the truck with use of a power drill for when stuff breaks. As of now, the door can only be opened with the roof up because of security and door/wall integrity needs.

Key to sketches:
- Yellow are AC mini split and Fridge appliances
-Red is compost toilet on slider
-White is stovetop and sink
-Dark ‘wood’ is built in cabinets and counters, one counter is removable to setup a bunk/berth under it for 1.5yr old
-Light wood benches will be storage trunks
-Large under dinette storage area, shown in water-like box, will hold water storage, house batteries, part of AC mini split, there will be access from outside on door side as well as from under feet in the dinette area
-Windows in green walls will be fixed and can only be seen once the roof is raised
-Windows in upper blue walls will be covered with hatches of foam/glass made to same spec as the adjacent walls, lexan inserts to be removable and attached via magnets depending on ventilation vs light needs
-Forward facing air vent with water trap not shown - still in design stages

13mm core - 5# density PVC - green glass vertical panels
16mm core - 5# density PVC - blue glass vertical panels
38mm core - 4# density PVC - white cloud vertical panels and horizontal floor panels (base floor and dinette)
Wheel wells to be built into this panel during infusion for strength
50mm core - 4# density PVC - roof, needs to hold eventual solar panels as well as insulate the equatorial sun/temps


Parked configuration with roof up:








Sleeping Configuration:
Bench seat backs become cots for 3yr and 5yr old over the kitchen area with 610mm of vertical space above their bunks. 1.5 yr old uses lower cot where countertop is removed. Personal bags stored in this area during transport are then stored on the floor of the dinette area. Dinette table drops to make a platform with the benches and all bench cushions connect to make a flat surface. Foam mattress unrolled on top of cushions for adult bed (1.83m x 1.27m) - this is a slightly trimmed double mattress size for NA folks.







Minimum construction elements to be completed. These are also the key structural components that will provide shell support and stability:
Fridge and AC will have to be purchased and at least their holding spaces built/accounted for, as well as the composting toilet.
Everything shown below to be built from PVC/glass panels (and lexan).
















So, first things first, help me create a laminate schedule for my panels. Pretty, pretty please!

 

@rxcomposite
@fallguy

The curse of being consistently competent has fallen upon your heads!

 

The foam should be relieved for tabbing, all cases; outside only.

I really like hexcel 18 oz woven roving 7544 here. It finishes nice enough to reduce fairing with reliefs to nearly nothing. And for a square walled structure, who wants to fair for days..

I am a little offended that you put my name in the title, but probably not for the reasons you may think. It is really unfair to pair me with a professional laminate designer like rx. My knowledge of laminates is really limited to my own experiences.

For example, some of these panels can also be made with a 10 oz woven.

The place where windows go... How are you going to mount the windows? You cannot screw them into light foams.

Another way to build would be to use all 6 oz woven and simple add a layer where needed. So, for the ceiling, 4 layers bottom, 3 top, walls 2 layers each side, same for floors.

Structures like these will need good reinforcements and so, I'd tab all critical internal intersections with something like 400g biax tapes times two.

Also, the roof will be tricky to keep from sagging as drawn. You really want some support. Light 4# foam cannot support a bumping trailer and 100kg of solar panels and the light foam cannot even allow bolting of the panels to it... Somehow, I'd say the solar design could be combined with roof support, but the details are not mine to hammer out.

All I have for now. The title should be edited to keep member names out. Asking a member to contribute is good.

 

Reckon it would be a whole lot easier and cheaper to just buy or hire a camper when you go from one continent to another.

 

@Mowgli even assuming that you manage to get (most of) this camper built during the next 4 weeks before you leave, and that you can get it shipped to Senegal (but I think this rather doubtful), have you researched the places where you can take it to easily and safely when you are there?

Maybe Senegal is safer than countries like Nigeria, but if it is on par, then I would not be too keen on going off camping 'in the bush' or by the sea, in view of the piracy and kidnappings that seem to be popular in this part of the world (or is this much exaggerated?).

Have you been to Senegal before, in that do you know what to expect, and are you familiar with the customs, languages and roads (are they suitable for towing a camper van?) .
I have just been having a look at the map of Senegal -
Senegal - Google My Maps https://www.google.com/maps/d/viewer?ie=UTF8&hl=en&om=1&msa=0&ll=14.9023057885797%2C-15.514678206488124&spn=5.107334%2C7.03125&z=8&source=embed&mid=1dl1dfSEP5Cwibo_Q5S0vIdz_wcI
Where will you be based? In Dakar?
I have only ever heard of Dakar, as being the end of the famous Paris - Dakar rally - but I have just been reading a bit about Dakar and the country in Wiki -
https://en.wikipedia.org/wiki/Senegal

I would agree with Mr E's sentiment above - and at least wait until you get there to see if you still have a need or a desire for a camper van.
Bear in mind also that the cost of shipping good everywhere in the world has escalated in recent months - have you received any quotes for shipping from the Eastern Seaboard of the USA to Senegal?
It certainly might be easier to buy a truck there, rather than ship one from the USA (?)

 

Thanks for the thought of including me in your quest for the design.

Forgive me for asking but what made you decide and the foam density and thickness? What is your background in mechanical design? Any dimensions of the box? Include base support. How will you attach this to the chassis?

You would get a wider audience if you will include a cross section of the box. This is no different from design of a typical boat. Telescoping, collapsible table, fixed furnitures that add to the stiffness of the structure, ect.

 

Hi all,


Sorry for going dark; one of my parents received an unexpected terminal diagnosis right after my first post and that has you can imagine consumed us all since the news.

My apologies to any and all that I may have upset with my inclusion of names in titles. This was a copying error as I had first drafted my post in a google doc and I grabbed multiple lines when I first set up the post title. Regardless, my sincere apologies to all and I was able to have the post title amended (THANK YOU ADMINS).

Many thanks to each of you that took the time to respond and contribute. I’ve learnt a great deal on this forum already and am clearly here hat in hand.

Well noted regarding tabbing needs; all foam would be relieved as such prior to lamination. This is one of the reasons I’m trying to hammer out so much of the design now, as opposed to most others building similar vehicle boxes that are using premade panels and subsequently simple rebate areas for attachment as they go during assembly. Or even worse, simply use butt joints with adhesive everywhere; this is the standard btw it would appear with both commercial and diy construction. With regards to fairing, I absolutely would appreciate the effort reduction as offered by the 7544.

I am going way off reservation with the windows. The few windows in the lower green panel walls will be glued in place permanently.

The higher windows in the raising blue panel walls will be from outside in:

1. A hatch made of foam/laminate the same or nearly the same as the wall panel. This will have weatherstripping to seal the hatches when closed.
   
   
2. Tightly woven mosquito netting on a thin frame secured with hook/loop. These are removable to enable the hatches to be opened and closed from the inside. I’m exploring other open/close options for the hatches that would enable these to be affixed semi-permanently but haven’t found anything simple enough as yet. Looking for ideas.
   
   
3. A lexan window pane that can be attached in lieu of the netting with a combination of hook/loop and magnets. The idea here is to eliminate the weight and money of window panes that open and close. Very often while occupied this box will the windows removed for ventilation reasons. The window panes will nest into a rebated bed also pre-relieved in the foam panels. When not in use, the panes will be stored dish style in a box.
   

Many thanks for the first offerings of ideas as to what weight roving to utilize. Ditto for advice regarding intersection taping and reinforcement.

I agree that roof is concerning. I’ve found others made with lifting roofs that are holding up fine after 5 years with a larger unsupported panel, but I also can’t afford to mess up here. One thing to note with regards to the final roof weight with solar, is that the actuators will be supporting the load when the roof is raised, and that when lowered the side walls are in effect doubled as the raising portion will rest on the lower wall section that sticks out. I release this isn’t even in the same category of support as a panel as thick as the two walls together, but it should help significantly. It is a simple matter to add in i-beam supports of foam/glass running width ways under the roof panel and this would have minimal to no effect on the design dimensions. Any ideas if I use the same foam as the walls how large these i-beams should be and how many are advisable?

As to the ideas and questions regarding hiring campers, using trailers, shipping, etc…

A provision of my employment and posting is that a vehicle of maximum 800ft^3 is shipped for me each time I relocate. Once I have the camper on the truck, it will stay with the truck and move with it during future postings to other locales. I have an allotment of household shipping assigned to me as well for the move and can pay out of pocket when I go over the 7000# designated for my family. I currently have approx. 1000# available for the camper, including interior items that cannot be mailed through military/diplomatic pouch mail (the fridge, ac unit, oversized recovery gear, winch, etc.). This stuff gets shipped as soon as I finish getting it together and schedule it. It usually arrives at my forward location about 10-14 weeks after I land.
Also, because of the kind of Visa that I have, my ability to own/register/use vehicles is different than other residents, even ex-pats. Trailers are a no-go, both for Dakar and the other known future destinations. From Seoul, we camped or tripped out of our 13 passenger van every single week when we were not locked down for Covid precautions and will do the same going forward as that's one of the big reasons I'm in this kind of employment in the first place. This makes short-term rentals non-viable as well as it's heaps of work to pack/unpack/setup a rental all the time, if/when they're even available and viable. Sometimes I also cannot rent certain vehicles because of visa/license issues mentioned above. Our truck will already be en route from South Korea by then as well, where I had it for the last few months after purchasing it from a Japanese export auction. Odds are the truck will be on station long before I get the habitat box completed.

I have worked in our Dakar location before temporarily, and have traveled more on the continent for work already as well. The security implications of overland travel here are very real, but they’re handled well by the folks I work with and I’ll only be going on routes/ to places already vetted. My professional AOR will be Morocco down to the Ivory Coast, and will be traveling a fair bit of that area by vehicles already for work. That said, there are many, many wonderful areas to explore in eastern Senegal alone, let alone Mauritania and The Gambia. I also have extensive professional experience leading supported and unsupported trips in the backcountry with school-age kids and this vehicle is intended to be a mobile platform to support my family’s intentions to make the most of our time. It may see the most use as simply an overnighter at the beach, a la a VW Westfalia Weekender bus setup, but that’s fine as well.

It also looks like my departure is going to be delayed for approx. 4 more weeks, providing more time to work this project, on account of the family situation. Additionally, I have just found out some much needed good news that we will have a two car-width garage at our new-to-us residence in Dakar. This is crucial as it now means I can do the assembly there as I will probably not complete as much here as I had originally planned.


The new goals accordingly are to the make all the panels, test fit the assembly, gather all necessary materials, and then ship that all on to Dakar for me to finish in a few months. This will cost less to ship as well if I go over my available ~1000#.

As for affixing the camper box to the rails/truck, I have researched and explored this ad nauseum. At 2x four points along the length of the floor, steel plates will be bolted onto the bottom through the floor with G10 fiberglass board on the inside as backing plates and inserts epoxied through the floor panel to prevent crushing when the plates are bolted. The steel plates will then be attached to a spring bolt assembly at each location on the frame rails. This is how wildland firefighting rigs with overload tanks attach their flatbeds and tanks to the same exact trucks and is the moreover the same methodology used by the two largest/most successfully offroad camper constructors in Australia. It’s the most proliferate topic on every overland forums I’ve researched in english, french and german. There are uhmw ‘pads’ if you will between the rails and subframe as well, and I may employ 4 LORD or ‘silent-block’ mounts as well to better handle the harmonic vibrations transmitted by washboard roads and dunes.

Below I’ve cross-sectioned the habitat in both directions, showing all the permanent furniture as well as the outer structure. Dimensions added this time (sorry for all the rookie moves).

I can now use a 5# foam for all the panels as I’ve been able to find it within budget. For foam density and thickness, I’m running somewhat blind. A bit of meta-research of similar builds shows that fiberglass over structural foam to be a best practice, but one very rarely taken. The closest build with regards to size and the key feature of a non-monocoque design (open ceiling for a lifting roof) is below. Go figure, the couple who built it have some considerable boat construction/repair experience. They used .5” H80 Divinycell.


Build - Fiberglass & Foam Truck Camper https://expeditionportal.com/forum/threads/build-fiberglass-foam-truck-camper.205977/

Most nearly everyone else who has used foam with either premade skins or FG has used PVC foam or worse. Most use SIP pieces or hang their foam composite panels on aluminum or even wood frames as they don't seem to understand or trust how a composite structure would be superior. There is simply no data out there that I’ve found in 2+ years of searching. I’m not terribly worried about the 1.5” core wall sections and floor or 2” core roof as those are somewhat standard in other builds utilizing PVC cores with considerably lower shear modulus numbers. The 0.5” and 0.625” green and dark blue short height wall sections are my big concern. I simply don’t have a way to judge

 

Can you show us the shell, no interior, with a typical three view drawing?

It can be pencil sketched. I am getting confused by your interior panels. Only show them if they go all the way across the structure or all the way to a final roof.

 

Also, tell us if this needs to be rated for
A-asphalt roads
B-rough gravel roads
C-terrible roads where speeds of 55kmh are maximum

 

The cabin of my Skoota is made from 600g glass and 12mm Gurit pvc. The bottom is made from 1" plascore and a lot more glass.

The places I bolt the cabin to the aluminum crossbeams are made with marine plywood.

I would bolt my cabin to any truck and allow it down a/b roads, but not c roads.

My roof spans 8' and is made with laminated beams 3x1/2" on 11" centers bonded to 6mm ply bonded to 12mm gurit corecell M with a 17 ounce biax glass top. It is supported inside and I walk on it, maintenance only. We designed it to support a 100# point load. The wood on the bottom makes it able to support the curves and acted as a stay in place mould over the beams.

Your bottom and roof need to be pulled out of the design. And the things like tables should be removed for now.

Yes, a system. But design the base first. T can't be 4-5# density core because it won't be able to be attached to the vehicle well.

Rather than designing the entire thing, start on the start of it which is the base. Then determine the walls and roof.

 

The reason I asked the question is that we need to tailor our response to your capability/experience. I see you have already built it up. It is structure analysis first before you decide on foam thickness/density.

1. How are you going to attach the structure to the chassis? This is concentrated load and you need some hard points like solid lumber or plywood for reinforcement. Foam itself will not hold.
2. You need rubber damper/insulator to isolate the structure from road use as FG has noted.
2. Have you considered a sofa bed? Where are you going to store the mattress when not in use?

 

please pay attention to the first two points

your foam densities will never support the effort

building the base well enough may take you the 4 weeks you have allocated; these things require cutting to fit to the vehicle, bonding, laminating each side, bonding isolation, and really these are not jobs done in one day

people doing composites work for the first times always fail miserably on time budgets by about half or double; pick your perspective

 

Also, because the structure is not supported by transverse members; the base must provide all the support and must be designed as a beam supported by the attachment points, so the loads are not uniform, but cantilever loads and this means the base must be stronger. If you can add a beam to the base; it would help..the for and aft walls would be such, but it is also important to know if they also extend beyond the chassis, which would be the third view from the drawing rx provides (sorry if I missed this detail in verbage, bit this explains the need for 3 view drawing of the base versus the isos of the entire unit.

But you have good support from rx if you are able to reply timely.

If others understand the supporting structure; please forgive me. Here, we have pickups with flat corrugated beds in them and wheel wells. But there are no practical attachments inside the truck bed; generally.

 

I would imagine it to be a beam because the chassis is already a long girder. Therefore there must be more than 4 points of support. The beam will then support the floor.

 

Here is a truck and chassis only.
Here is a typical US truck n camper. Truck bed supports entire camper base. Wheel wells are in the way is all, so the camper design is made narrower for backing into the standing camper.

Perhaps this is correct, but I am wondering if the truck has a bed or just chassis; all our non-commercial trucks here(millions) have a bed and support under the entire base; unless it, like many campers extends beyond the bed (like the purple in my drawing). Some campers extend 4' beyond the bed which means they are made stronger..the picture shows a small cantilever.

Or, if the truck is only a chassis like you show in your picture and the first picture I included; the sidewalls are unsupported and require a much beefier structure than a camper supported side to side along the entire base.

I apologize for the layout of my reply. I could only get pictures to load a certain way. Also, a camper that must be lowered onto the chassis must be very strong on lifting corners and be hardpointed there.