Fiberglass Repair

[Denise Jones]

Hey Ya'll
My 76 Scamp has a few places where the fiberglass is damaged on the back bottom edge on sides near bumper where it has possibly hit a high spot going down steep gravel driveway.

I am wondering if I could just cut these edges out since they are only about 2" and nothing behind it. Shape it and then put new plastic edge around bottom.
Anyone modified the shell like that? Or see any problems with this idea?

[David Tilston]

Denise, Why not use fibreglass instead of a plastic edge?

I have found this thread very helpful:
https://www.fiberglassrv.com/forums/...ass-52498.html

[Denise Jones]

Thanks for the info.
I was thinking about cutting down and reshaping the back corners just a bit because of the damage which may continue due to steep gravel driveway and putting new scamp trim all around edges. Also have some cracks around back bumper. Would you repair them as thread describes?
Thanks for all the great info you guys offer!

[kip22]

I've used bondo with fiberglass in it for small patches/holes. If its bigger than an inch or so you need glass mat first. I've used bondo with glass mat also which worked out fine and took paint after no prob.



What I've noticed though is that the bondo is a lot harder than the fibreglass so you have to be careful when sanding to really target the bondo area you want to sand down. I've still got half a tub of it left but I'll probably switch to Fiberglas resin when its gone.

[Jon in AZ]

Originally Posted by Denise Jones

Hey Ya'll
My 76 Scamp has a few places where the fiberglass is damaged on the back bottom edge on sides near bumper where it has possibly hit a high spot going down steep gravel driveway.

I am wondering if I could just cut these edges out since they are only about 2" and nothing behind it. Shape it and then put new plastic edge around bottom.
Anyone modified the shell like that? Or see any problems with this idea?

That lip that extends below the floor serves an important function. A fiberglass tab connects the shell and floor around the entire perimeter. There's one on top and one underneath that is bonded to that lower apron of the shell. You could trim away a little, but trimming too much or too close to the floor could compromise the structural integrity of the shell-to-floor attachment.

[redbarron55]

If those cracks are around where the frame rails exit from under the back floor and connect to the bumper you might have more to fix than you realize.
The whole shell is really supported in the area above the frame where the floor sit on the frame rail. The fiberglass tabbing from the shell to the OSB is all of the support that there is and if it fails the stresses from the frame cause the fiberglass to crack in this area.
Look carefully for rot in these areas from water leaking from the rear window.
There is not a lot of strength in the frame to shell connection and all of the forces are concentrated here and in the front of the shell.
There is really very little support from the tabbing along the sides as floor in that area is merely screwed to the frame with a few (probably rusted) screws and provide little or no stiffness.

[drdoyle]

My preference to fiberglass repairs is west system ultra slow epoxy resin and fiberglass cloth. Sometimes carbon fiber cloth. Wet the glass with a small brush and use a plastic squeegee to flatten it out and reduce resin content. Use watertight epoxy finishing filler to finish the surface - with a plastic squeegee and very thin, just enough to fill the weaves.Interlux Watertite Epoxy Filler YAV135KIT/L

[David Tilston]

Originally Posted by drdoyle

My preference to fiberglass repairs is west system ultra slow epoxy resin and fiberglass cloth. Sometimes carbon fiber cloth. Wet the glass with a small brush and use a plastic squeegee to flatten it out and reduce resin content. Use watertight epoxy finishing filler to finish the surface - with a plastic squeegee and very thin, just enough to fill the weaves.Interlux Watertite Epoxy Filler YAV135KIT/L

Every now and then someone suggests the West system for a trailer. Why? Our trailers are made with polyester resin. While the West system will stick to polyester, polyester will not stick to the West system. The West system is for boats. I don’t tow a boat.

Carbon fiber cloth?!? Under what circumstances is this required? Clearly drdoyle has money to burn.

[FRED SMAILES]

Totally agree David!
Polyester resin and glass may will give great repairs. Plus probably stronger than the original chopper gun applied fiberglass.

[redbarron55]

The reason I use Epoxy is that I have it to make repairs on many things.
Epoxy will basically stick to anything and is waterproof and holds up well.
The cost is low compared with doing it again.
When I rebuilt my Scamp I covered the new floor with fiberglass cloth and epoxy resin on both sides and the edges to keep water away from the wood.
The epoxy is pretty much waterproof if water leaks in and puddles on the floor.
Polyester resin is not (long term as witnessed by the many many boats made with polyester with rotten stringers and transoms.
Plus it is harder to get a longer set time at higher temperatures like we have here in Florida.
But to each his own.
I spent about $150 on Epoxy resin to redo my Scamp and have some left over for other projects as well.
Polyester will work OK and save some money.
That said the grandkids will thank me for the extra money spent in 30 years when they don't have to replace the floor in an 80 year old Scamp...

[David Tilston]

Originally Posted by redbarron55

The epoxy is pretty much waterproof if water leaks in and puddles on the floor.
Polyester resin is not (long term as witnessed by the many many boats made with polyester with rotten stringers and transoms.

I think you're making my point. It's for boats. I have a very leaky Trillium 1300:
https://www.fiberglassrv.com/forums/registry/2260/

Which I parked, tilted front up on a hill to keep the water from rotting the plywood in the floor. However, I didn't think about the water pooling in the rear dinette. When I looked at it, after about a year, the dinette was almost full of water. I drilled a hole from inside the dinette seat to drain the water. There was no perceivable damage to the fibreglass. I’m sure that many years later there would have been.

Originally Posted by redbarron55

Plus it is harder to get a longer set time at higher temperatures like we have here in Florida.

You have me there. I just got used to only mixing up enough resin for 10 minutes of work and I go fast.

Originally Posted by redbarron55

I spent about $150 on Epoxy resin to redo my Scamp and have some left over for other projects as well.

I bought $50 CDN of resin and had some left over, but I found out that after one year, it's no good anymore. Does epoxy have a longer shelf life?

Originally Posted by redbarron55

Polyester will work OK and save some money.
That said the grandkids will thank me for the extra money spent in 30 years when they don't have to replace the floor in an 80 year old Scamp...

I like the way you think.

[Denise Jones]

Is this image indicative of the problem you are referring to?
I crawled under today and didn't see any rot but may not know what else I should be looking at.

[Denise Jones]

Wondered if this crack around back bumper is what you were talking about that might show a bigger issue? I looked under and found no rot but not sure what else I should look for. Could you possibly explain?
Thanks any help is appreciated.

[FRED SMAILES]

IMO, Unless there has been a hit on something that crack is probably the result of vibration differences between the body and the frame going down the road.

[Denise Jones]

So maybe not as severe a problem as redbarron55 mentioned? That thought scared me since it would be way out of any of my abilities to correct it.

[FRED SMAILES]

I don't think the crack in itself is great cause for concern if the floor, frame and attachments all look ok. 50 or so years, the stress will show up somewhere.

[Denise Jones]

Fred, I just looked at your trailer story. Fabulous use of space! Very creative! You made every space useful. Love it.

[FRED SMAILES]

Thanks Denise.
Like most everyone here, lots of fun modifying and using our boler has created many great memories.