Building a truck bed shell

[Doug Briggs]

Think marine: canvas-laid decks and cabin tops. And skin-on frame boat hulls.

Canoes

Greetings and welcome to 'The 66' skin-on-frame canoe. Originally envisioned as a lightweight double-paddle pack canoe, the 66 evolved into a complete canoe building system that gives you the...

www.capefalconkayaks.com

Duh! I haven't been on the water enough lately. My thinking has become landlocked.

I actually built a skin on frame canoe. Unfortunately I used inferior wood for the ribs and it didn't last long. Dacron over a roving of kevlar on an oak rib and ??? stringer frame. It was a beauty.

 

[Dakine]

Doug, Fasteners just hold things in shape till the epoxy sets.
The 1x2 ribs just gave a place to butt the sheets of plywood.
Scarf joints are necessary for boat construction but a bit elegant for a trailer.
The layer of epoxy/glass over the plywood added a great deal of stiffness to the structure as well as providing a durable surface for paint and graphics.
An air staple gun with 1" SS staples is fast, a trick I learned from the Gougeon Brothers in nearby Bay City.
You can hold things with one hand while stapling away.
I don't know why you would use canvas when glass is stronger and doesn't rot.

 

[Wilhelmson]

Not sure if you're talking about wave-corrugated polycarb like Tuftex/Vistalux or twin-wall/multiwall Coroplast-style polycarb like for greenhouse walls?

Clear Greenhouse Plastic Sheets - Greenhouse Megastore

Cover greenhouses and other structures with high-quality plastic sheets that have the best combination of strength, light transmission and heat insulation.

www.greenhousemegastore.com

If it was *my* design - and given the curvature in the ribs above- I wouldn't do either of those. I'd go with @Doug Briggs original plan of wood panel with strategic skylight cutouts. Then cover the whole thing in canvas (including skylights) and saturate with epoxy (including skylights).

Yeah the flimsy stuff they use on 50 foot semi trailers. Careful with the forklift!

 

[Doug Briggs]

Doug, Fasteners just hold things in shape till the epoxy sets.
The 1x2 ribs just gave a place to butt the sheets of plywood.
Scarf joints are necessary for boat construction but a bit elegant for a trailer.
The layer of epoxy/glass over the plywood added a great deal of stiffness to the structure as well as providing a durable surface for paint and graphics.
An air staple gun with 1" SS staples is fast, a trick I learned from the Gougeon Brothers in nearby Bay City.
You can hold things with one hand while stapling away.
I don't know why you would use canvas when glass is stronger and doesn't rot.

I was looking for confirmation that glued joints would be adequate and you provided that. Thanks. My rabbets and dados relieved me from having to add ribs. I did need lots of clamps to hold it together, though. And I had to do the glue up in stages because of how many clamps were needed.

I looked up fiberglass and the amount of epoxy I'd need. I think the $250 or so to cover the whole unit would be time and money well invested. Then paint.

Thanks for your comments and suggestions.

 

[Joby Graham]

I was looking for confirmation that glued joints would be adequate and you provided that. Thanks. My rabbets and dados relieved me from having to add ribs. I did need lots of clamps to hold it together, though. And I had to do the glue up in stages because of how many clamps were needed.

I looked up fiberglass and the amount of epoxy I'd need. I think the $250 or so to cover the whole unit would be time and money well invested. Then paint.

Thanks for your comments and suggestions.

Possibly coat the exterior with a bed liner material, like the off-roaders do to their vehicle's bodies? Comes in colors (Du aB

 

[Doug Briggs]

The winch and pulley system. One cable pulls four cables. The units in the middle are double shiv pulleys. All of the eyes I made are Molly Hogans or Flemish Eyes. It is a spliced eye.

These are samples of a Molly Hogan.

I hung the shell on the winch and pulley system today.

It is hanging just barely above the floor as a stress test.

In the fully lowered mode.

Detail of the connection to the shell. I pulled the short carriage bolts that connect the steel angle to the side wall and replaced it with the eye bolt. The 2x4 is there to keep the cable away from the shell should it swing a little.

I'll raise it onto the truck in the not to distant future.

 

[Doug Briggs]

The project continues.

Today I built the roof section. The two arches will support the three sections that will make up the roof itself. They provide a platform for joining the edges which will be butt fitted. As I'm going to fiberglass the roof, resorting to scarf joints seemed superfluous. Additional arches will be added while adding two of the sections which are 48 inches long by 60 or so inches wide. I'll fit the sections individually and when they are all in place I'll sand the edges to a small radius. I won't be fiberglassing the remainder of the shell in total as it is quite sturdy as is. I will add fiberglass to the outside corners to reinforce them from impacts.

 

[oldschoolskier]

Looks good. Just heavy.

 

[tball]

Such a cool project Doug!

I know you are far down the road and this is way outside any expertise of mine, but I'm liking the idea of greenhouse polycarbonate for part of the roof or the skylights.

I saw this very cool geodesic dome greenhouse up in Leadville and the polycarbonate material seems remarkably strong:



A company in Pagosa Springs makes that greenhouse dome. It's a long drive, but I wonder if they have scraps you might be able to use? They provide the specs on the two polycarbonate materials they use to build their greenhouses here:

High Quality Polycarbonate Greenhouse Glazing - Growing Dome

The Growing Dome 16mm polycarbonate greenhouse provides insulation, great light transmission, & long lifespan, even under extreme conditions

growingspaces.com

 

[Doug Briggs]

Looks good. Just heavy.

I admit is is not light. It is a lot lighter than a camper, though and it will serve my needs, I believe. I think I could have made the sides out of 1/2 inch ply instead of 3/4 and saved a fair amount of weight. The steel angles aren't light, either (40 - 50 pounds combined), and probably overkill. I was fearing a self destructing box leave a trail of plywood, bikes and skis along the highway.

Such a cool project Doug!

I know you are far down the road and this is way outside any expertise of mine, but I'm liking the idea of greenhouse polycarbonate for part of the roof or the skylights.

I saw this very cool geodesic dome greenhouse up in Leadville and the polycarbonate material seems remarkably strong:



A company in Pagosa Springs makes that greenhouse dome. It's a long drive, but I wonder if they have scraps you might be able to use? They provide the specs on the two polycarbonate materials they use to build their greenhouses here:

High Quality Polycarbonate Greenhouse Glazing - Growing Dome

The Growing Dome 16mm polycarbonate greenhouse provides insulation, great light transmission, & long lifespan, even under extreme conditions

growingspaces.com

Bucky goes to Pb to grow cucumbers. I think the person harvesting is a client and the presenter is her sister in law.

Ya, my design is beyond being able to incorporate rigid panels at this point. I do have a friend who was an inspiration for building a shell on a truck. He is up to his 4th one called MD4, so you never know. I may be building a TS2 (Truck Shell 2) sometime in the future.

 

[tball]

Bucky meets Pb to grow cucumbers.

How about a geodesic dome for your trailer!?!?



I'm sure most here know about Buckmaster Fuller (Bucky), but here's a reference in case anyone doesn't:

Buckminster Fuller and the Geodesic Dome Greenhouse

The first known greenhouse application of the Buckminster Fuller geodesic dome design was the Climatron® built for the Missouri Botanical Gardens in 1960.

growingspaces.com

 

[cantunamunch]

Bucky goes to Pb to grow cucumbers.

Panda-free?

 

[Doug Briggs]

Panda-free?

 

[Doug Briggs]

I continue to make progress on the shell. The last of the exterior shell construction is complete.

The next steps are to fabricate the 10 foot sections of 1/4 inch plywood for the triangular sides that will fold up when the roof is lifted which means more scarf joints. I have built a jig that allows me to quickly make the joint with a router. As it is only 1/4 inch, the joints are not as big as the ones for the 3/4 inch plywood.

Color has nearly been settled on. I thought I'd go with black on the area below the roof, with white on the rooftop. Pricing two colors of paint, I'm using Petit EZ-poxy one-part topside paint (a marine product), and to get the quantities I need would need to hope that the quarts I'd buy provide necessary coverage or get a gallon of single color. As it is easier to heat up the inside, when needed, versus cool it down, I've decided on white. Any suggestions for an alternative color for thermal and aesthetic reasons would be welcomed.


Truck photo for color reference.

I had thought I'd paint the interior white for brightness and easy of visibility, but have decided given the light color of the wood, that I'll just urethane it. It will reveal all the warts as well as construction notes I wrote on the pieces to keep the straight, but if I grow tired of that, I can always paint it, too.

I'm going to glass the roof and its 3 inches of 'frame' for the sake of durability and additional stiffness, but I'm very happy with how strong the roof is as is. I had a suggestion from a woodworking friend not to rely on the arches solely for roof shape and added a couple of cross pieces that will prevent the roof frame from spreading under load. That proved to be a wise suggestion; I'm glad I implemented it.


The arches result in 3/4 of 'arch' once bonded with the roof while the two 1-inch cross pieces only impose slightly in the space below the roof. FYI, this is the roof raised from the front, not the back, as it will be completed.

 

[cantunamunch]

As it is easier to heat up the inside, when needed, versus cool it down, I've decided on white. Any suggestions for an alternative color for thermal and aesthetic reasons would be welcomed.

How about a contrast strip to relieve the slab'o'white? Like a boot stripe except truck-shaped.

 

[Doug Briggs]

How about a contrast strip to relieve the slab'o'white? Like a boot stripe except truck-shaped.

That's a good idea. It doesn't have to be white, though, but a color that won't promote solar gain.

I'd entertained having an artist put a mural on the side á la 70s van, but I also want to be a bit stealthy. I was thinking a false company logo, too. I will likely add windows later, so those are not really valid options, amongst other reasons.

I've read about vans with false ladders on the top that disguise solar panels. That enhances stealth so that urban 'camping' can be more discrete, but I don't really plan to go urban. Bike and ski destinations are my goal.

 

[cantunamunch]

One of my neighbours has a vinyl wrap business - not sure if that's a possibility for you.

I'd entertained having an artist put a mural on the side á la 70s van,

- The first reflexive thought I had was to have vertical arches, Conestoga wagon style
- The second reflexive thought I had was to finish the roof side section in (stained?) wood grain (3" wide) and only white the actual top and lower sides.

But never mind trompe l'oeil games for now, you need to have this finished.

That's a good idea. It doesn't have to be white, though, but a color that won't promote solar gain.

Sure, I was just using 'white' as a place holder. Though picking something other than white is likely to make it more obvious rather than less.

I've read about vans with false ladders on the top that disguise solar panels. That enhances stealth so that urban 'camping' can be more discrete, but I don't really plan to go urban. Bike and ski destinations are my goal.

Do you plan on having side lights on the shell? I don't mean truck trailer contour lights, but ones you can actually use for side, back, front illumination while stopped? Integrating those with the shellwork can bring visual elements.

Also, what are you doing for a CHMSL?

 

[Carolinacub]

@Doug Briggs , This has been fun watching this come together. I generally check at least twice a day to see if you have added anything. I honestly had no real vision of what the end result was going to be but now it's all becoming clear. Congrats my friend this is a great project.

 

[Doug Briggs]

@cantunamunch , I like the idea of the natural wood 'boot' stripe for the roof frame which is a little less than 3 inches in height. I have a client that does car wraps in addition to being the best sign maker in the county. I may have him do some lettering. Perhaps my business logo somewhere, too. Not because it's my logo, but because I like it.

 

[Doug Briggs]

@Doug Briggs , This has been fun watching this come together. I generally check at least twice a day to see if you have added anything. I honestly had no real vision of what the end result was going to be but now it's all becoming clear. Congrats my friend this is a great project.

Thanks. I've saved my notes and obviously taken a lot of progress photos. It is turning out like I imagined. I know that I didn't provide a very cohesive description of the design. I need to figure out windows, but they aren't crucial as it is easy to cut out holes to install whatever I come up with. I have the windows from the shell I scavenged for the rear window and cab/shell gasket. I have to decide whether they are too big and infringe on structural integrity. One is actually drawn on the inside so I could realistically evaluate whether the remaining wood would be sufficient.

I have just been fine tuning my idea of how the bolt-on extension that would enclose the lowered tailgate might work. I have some fun ideas for that. I probably won't address that until next spring, though. I want to field test it in it's current configuration. While I keep saying it isn't a camper as it will have no built in kitchen, etc., I do plan on sleeping in it some. Maybe a Wolf Creek trip? Or beyond!