Pop-up camper build using composite panels

[matt_devon]

Hi! Long-time lurker and I decided that it's finally time to start posting. This thread will mostly be a recap of my pop-up truck camper that I built between October 2022 and April 2023. Also big thanks to underkill for their excellent build thread https://forum.expeditionportal.com/threads/build-fiberglass-foam-truck-camper.205977/

Summary​

• Vehicle is a 2019 Ford Ranger FX4
• I used 1 inch and 1.5 inch polypropylene honeycomb core panels with FRP skins sourced from CarbonCore
• Resin: Total Boat traditional 5:1 epoxy for most of the build
• Fiberglass: Pre-cut tape ranging from 1 to 6 inches in width. 1708 biaxial cloth for high stress areas and 6 ounce woven everywhere else.
• Thickeners: cabosil and/or glass microballoons
• Fairing compound: Total Boat Total Fair or epoxy+ glass microballoons
• Joinery: Butt joints with cabosil-thickened epoxy fillets on the inside radii. Outside radii got 1/4 inch or 1/2 inch round-overs, faired smooth, then glassed over with 1708 biax or 6 ounce cloth.
• Total weight of the bare camper is about 250 lb (not including mattress or interior build-out)
• Build time: about 400 hours of nights and weekends spread out over 6 months
• Cost: roughly $4,500 USD

Here's how it all started back in October 2022:



And here is the (mostly) complete camper in April 2023:

Build Process​

Disclaimer: this was my first time working with composites and I made plenty of mistakes so this is by no means a how-to guide. I started the build with many, many hours of research and drawing up designs. Once I was reasonably sure I had a workable design and the confidence to start what could be a multi-year project, I placed an order for four 1 inch composite panels and two 1.5 inch composite panels from CarbonCore.

First step was to sand the panels front and back in preparation for epoxy and eventually paint. I sanded the panels using 60 grit; dust collection and a good respirator are must haves imo.




























Layout and cutting everything to size using a track saw. The track saw isn't necessary but its dust collection is much better than my circular saw.


Starting to bond panels together, I filled the exposed core with microballoon-thickened epoxy or total fair before bonding using cabosil-thickened epoxy.The core to skin bond with epoxy is not great by itself but the skin to skin bond via fillet or fiberglass is very strong. These large fillets were made using cabosil-thickened epoxy and formed using a silicone spatula.


Profile view of filled core. After the bonds cured, I used my router with a 1/2 inch radius bit to round the outside radii. Next, I filled and faired the core exposed during the round-over.


Laying 1708 biaxial cloth over the joint (this joint is what connects the topper to the truck bed so I wanted extra strength here, this was the only joint where I laid 1708 on the inside and outside of a corner)


Kept repeating that process and eventually the camper started coming together:


to be continued...

 

[matt_devon]

Bonding the fixed cabover portion of the bed into place. The sides and the roof are all 1 inch panels but I opted for 1.5 inch panels for the bed floor.


Kerf cutting the side panels that wrap around the above bed corner. I made a few test bends with scraps then knocked out the real pieces on my table saw using a cross-cut sled. You can also see the the end prepped as a tenon for inserting into a mortise where this section gets merged with the rest of the side wall. I made my tenons by making a shallow cut on the shoulder using my track saw that just pierced the FRP, then I separated the waste FRP from the tenon using an oscillating tool. For the mortises I just chewed out pockets using the oscillating tool and popped the honeycomb core out using pliers.


Final test fit before returning the shell to the shop where it would live until it was completed. I don't remember the exact weight at this stage but I was able to move the camper around solo by carrying it while holding the bottom of the cab wall.


Glassing the outside corners (I quickly learned that laying fiberglass on vertical surfaces is not fun). I eventually started wetting out the cloth on my workbench before transferring the saturated fiberglass to the camper and touching up dry spots and rolling as needed. The green blocks inlaid into the rear of the camper are 3/4 inch thick blocks of G-10 that I placed anywhere that would eventually get a through-bolt for hardware. The panels alone aren't strong enough to resist the compression of a bolt over such a small area.




Adding a top rail to stiffen the shell


Working on the rear hatch


Installing support pieces for the removable part of the bed and doing some early fairing work


Fairing and sanding then fairing and sanding then fairing and sanding etc.

 

[Victorian]

That's cool!

 

[ITTOG]

That's cool. I will be following along.

 

[matt_devon]

Moving on to the roof and kicking myself a little bit for making the camper just over 96 inches long. Joints are half-laps and seams were glassed.



Fitting the roof to the lower part of the shell. I intentionally oversized the roof by about 1/2 inch on all sides then trimmed it to its final size by using router with a flush trim bit and the body of the camper as the guide.

Test fitting the slide-out portion of the bed


And finally, after many hours of sanding the camper was finally ready for paint. My one real regret of the whole build was my paint choice; Rust-oleum topside paint and primer. I chose it because of its low price and the ability to roll it on. Building up thickness involves rolling on many thin coats with sanding in between and my final product was not particularly hard. I am pretty happy with how the interior turned out but I will probably repaint the outside at some point with a two part marine paint or bedliner. Thankfully painting the exterior was much easier than painting the interior with all of its nooks and crannies.


Primer on and spots where I needed to go back with filler are marked


After several coats of paint with several more to go

 

[NVLOC]

Really enjoying this one, thanks for taking the time!

 

[Sparse Gray Hackle]

This is an impressive build. Thanks for sharing!

 

[WanderingBison]

Incredible build - thanks for sharing and inspiring those of us who are considering a DIY composite build


Sent from my iPad using Tapatalk

 

[rruff]

Great job, Matt... thanks for sharing!