I am an idiot in this stuff, but what about taking a foam sheet and wrapping it in FRP? Would that give you more rigidity, lighter weight and an easier production method? I suspect you'd want a foam that didn't melt when covered in resin :)
I am an idiot in this stuff, but what about taking a foam sheet and wrapping it in FRP? Would that give you more rigidity, lighter weight and an easier production method? I suspect you'd want a foam that didn't melt when covered in resin :)
I am doing 1/4" foam sheet with 6oz cloth on both sides. It's a high density foam that doesn't melt with polyester or epoxy. We bought it to use on the deck of surfboards for impact resistance, but we didn't like how it turned out so we've got a few sheets left over in storage.
My dad had the idea to glass the inside of the lid first. This will keep it straight while I attach it to the frame.
This is the foam I'm using. Warvel was a company in NC who made everything from RV shower stalls to school desk tops to surfboard blanks.
This foam is 2 feet wide so I have to seam it. I'll put the foam seam down the middle
My cloth choice for this step is 4oz warp.
My cloth is 30" wide so I had to seam it too. That seam covers the foam seam.
870 grams mixed, resin and hardener
First layer trimmed and ready to attach. How? I don't know yet
Staples are the answer I think?
Due to the curvature I did the sides with 2" strips
Not perfect, but that's what Bondo is for.
Now to start glassing it all together. Tomorrow we begin!
It feels so much stiffer with even a little fiberglass. There are small strips attaching the ribs to the top. I found it easiest to soak the strips in my bucket of resin. I was measuring the hardener and resin (.45 to 1.00 by weight) at the surfboard factory then carrying it 1/4 mile to the garage and mixing it when I got to the garage. Haven't had a hot batch yet, but it kicks pretty fast.
90° corners are the enemy of fiberglass. I bought a 1/4” round router bit to soften the edges. There are a few gaps still that I am bondoing so I get good adhesion.
Just to keep you motivated
In reply to Steve_Jones :
Haha! That's awesome. Way better looking than mine will be
On to the walls. I did the corners, inside and out, with little strips of cloth. Now for the outside I'm doing full 6oz sheets. I familiar with working on horizonal surfaces, so vertical is a challenge. I ended up stapling the cloth in place.
I'm fighting a comfort conundrum. If I open up the garage doors the temperature is fine but the wind blows the cloth around. So instead I drip sweat and have an easier working condition.
Very cool! I'm also jealous of your surfboard factory. Whenever I do a board I have to convert the garage.
Stoked to see how the topper ends up
In reply to Shavarsh :
I am so lucky to have that space. It makes side projets with fiberglass so easy.
I had my first hot batch. I didn't get the resin out of the pot fast enough. With that much thermal mass it heats up fast! I bet the resin was close to 150° when I gave up. Best thing to do in that case is get it on the board(topper) and thin so it can radiate the heat. Luckily the only dry spot is the front little bit
To anybody who regularly fiberglasses right angles, I'm so sorry. This is way harder than the ½"+ radius curves that I deal with on surfboards
I just wanted to see what it looked like so we propped it up. It looks taller than the roof of the Jeep, because the lid doesn't fit all the way down yet. Plenty of stalagtites hanging off not allowing the lid to fit all the way down.
It's gonna take a lot to smooth this out. Plenty more cloth and Bondo ahead of me. But I like the concept.
Somebody at least could sleep in this little short bed.
You might like these guys, if you haven't seen them already. These dudes go *hard* into fuel economy. They have a tire engineer from Michelin(?) who is basically a tire pressure/road contact/traction demigod. I want to implement a few things I learned from them on my Crosstour once I'm working again. I wouldn't be surprised if your buddy with the Dodge is on there.
buzzboy said:To anybody who regularly fiberglasses right angles, I'm so sorry. This is way harder than the ½"+ radius curves that I deal with on surfboards
Put the mat on the "Bias". If you put it at a 45⁰ angle the strands only have to make a 45⁰ angle to turn the 90 degree sharp corners. I learned that after doing most of the edges of the LMP360 stuff and having to go w much of post cure resin fill when the voids opened when the glass fibers didn't want to turn the 90⁰ corners. I did some of my patches with biased cloth and it basically layed flat no issues.
In reply to Turbo_Rev :
I Read about this concept on EcoModder. I implement a lot of hypermiling techniques in this truck. I want to increase my economy without decreasing the abilities of the truck.
In reply to nocones:
That is the right way to do it! I should have done that for the smaller run. Not practical for the 60"x6" piece but I could/should have for the 16"x6" piece.
The busy season finally ended. July and August were crazy as always. Back to the top, and I have a deadline fast approaching!
I ground out and filled all the inside 90°s with roving. Should make it stronger and easier to fiberglass over. Everything is getting a round of sand>fill>sand>fiberglass>ad nauseum
The measurements for the window are perfect. But something really dumb I did, forgetting that RV windows don't have 90° corners like house windows. How was I this dumb‽
I'll do some little foam filler panels and fiberglass them. Only serve to make it waterproof.
we have all assumed things .... wrongly
Round edges installed. Crisis averted. 1 month until departure from NC. Less than 31 days to get this done. I think I can, I think I can...
The mess continues to grow!
Test fitting the top, and I like it. Really gives a HMMWV kinda look. I did find out though, the lid is slightly too tall, like ½” too tall.
Visibility out the rear view is still great. Almost no change. Can barely see the top in the side mirrors either.
To fix my over height issue I'm grinding ½" off the leading edge of the top.
An aside today, for comparison to surfboard manufacturer. For the topper I'm going for light weight body filler. Here are some photos of how we do it at work. Just a few random surfboards being built or repaired.
Fiberglass lays down with rough visible weave. Strong and light but we want it smooth.
We start with a "hot coat", so named because we kick the resin quicker which gets hotter(at least polyester). The resin is thinned using styrene for polyester or xylene for epoxy. This is brushed on very thin.
The cured hot coat is shiny but not terribly smooth.
Lastly we sand that thin coat of resin with 100, 150, 220 and spray on a surfboard specific clear coat(I don't know what it is). This gives us a very smooth and straight finish.
On a polyester surfboard we could also come back after the hot coat with another layer of special gloss resin that we sand down to 800 wet and then polish with #2 compound. Epoxy resin gums up the polishing pad so that technique is specific to polyester surfboards.
2 weeks left
On to body filler
Hinges fit
I told my dad yesterday, "this is the last batch of epoxy." He chuckled.
After two passes of bondo and sanding i had high spots on this one row of staples.
I would say "last batch of epoxy" but I know better this time
Black does not hide defects. Taking a photo from 15 feet away does
In reply to buzzboy :
When my work is less than satisfactory I simply step further away and take another picture!
You'll need to log in to post.
