Epoxy Oh NO

[jacwjames]

I've been working on repairing an area of delamination, about 4'X6', passenger side from the bedroom window back.  I had a leak at the belt line, I think it was where the rear cap met the roof, there is a hump there and the beltline didn't have a good seal. 

Anyway, I've removed the beltline, dryer vent, bedroom window and awning supports.  I was able to get epoxy into the void from the dryer vent opening and window, initially using a large syringe with tubing attached letting gravity help.  The last pour was up hill so I rigged up an injection rod using copper tubing, compression fittings, a heavy plastic bottler and a blow gun.  I'd fill the bottle, attach it to the tube that was already in place, turn the bottle upside down, inject air in pulses and it would push the epoxy out.  I had rigged up a form using a piece of smooth plywood and then 2X6 &10's laid horizontal, and then after injecting the epoxy I'd put pressure on the whole thing using the side of my shop as a place to wedge against.  I started low, and did 3 smaller pours and then the last one was all up hill . 

I had worked with epoxy before and tried to anticiapte where it may flow out of .  I caulked the 2 electrical panels below, there was a large gap there.  I taped all the seams.  My last pour I silconed the dryer vent to try and prevent any coming out there.  there was some leaking on the inside down the engine compartment back wall but no way to stop that.  What I failed to do was plug the holes the dryer vent was attached to the side of the motorhome with.  Epoxy ran out there and I have a ~6"X12" area of dried epoxy. The epoxy is a West System 105 & 206 slow cure hardener.   Is there any way to get this off without damaging the paint, although I'm can sand it off and repaint I'd rather not.

Here are some pictures of the project, with the last one being the epoxy problem OH NO!!!!

[Seward G]

I'm impressed by what you accomplished!

[jacwjames]

I was also until I pulled the plastic off from around the vent and saw the I had sprung a leak. 

But no point crying over spilled milk, I have to figure out a way to get the epoxy off or fix & paint it. 

[Ivan K]

You probably know that there are epoxy removers but I have no idea what it would do to the paint... if it is cured hard, you could try carefully scraping it off with a razor blade but it would be a lot of work on a large area. No less than 90 degree angle and tape off the blade corners. That's how clearcoat runs are successfully removed, then buffed out.

Good job BTW.

[jacwjames]

14 minutes ago, Ivan K said:

You probably know that there are epoxy removers but I have no idea what it would do to the paint... if it is cured hard, you could try carefully scraping it off with a razor blade but it would be a lot of work on a large area. No less than 90 degree angle and tape off the blade corners. That's how clearcoat runs are successfully removed, then buffed out.

Good job BTW.

So your saying hold the razor blade perpendicular to the surface and scrap? 

[Ivan K]

1 minute ago, jacwjames said:

So your saying hold the razor blade perpendicular to the surface and scrap? 

At a right angle so you don't cut into it, yes, just scrape it off in tiny layers. It needs to be cured hard otherwise it will just roll and smear around. Well, that's what it would do with a clearcoat and may not be a problem in your case unless the paint softened. This is why we don't try to fix a clearcoat for a week at least.

[vito.a]

Great job!  Looks like a mad scientist work shop.  

Have you tried scraping the excess epoxy?

[jacwjames]

Not as Ivan described  but that will be my next move.  

 

I've been working on this for ~2 weeks, taking it slow.  Initially I was using fast cure hardener but I switched to slow cure to give me more time to work with it.  The first pour I did to seal the bottom seams which mostly worked.  I then did a couple pours using gravity.  The last part I knew was going to be a challenge since I could gravity feed it so I came up with injection method.  The copper tubing was rigid enough to push in place and move it around.  I had the wire braided hose with the compression fitting on one end which worked out great.  I was concerned about using air pressure so started out with 20 psi in short bursts and then upped it to 30 psi which pushed it pretty good and then at the end I could hear it spraying.  Seems like it got pretty good coverage. 

In my previous life I was know to come up with some pretty crazy ideas which most of the time worked. 

[JDCrow]

Sooooo cool. This is awesome! 

[jacwjames]

Thanks   I was nervous when I started this but not many options when you have delamination, either you fix it or you don't. 

Not going to lie though, I know a guy who use to be the shop foreman for TN RV, a large repair facility.  I asked him about what I planned to do and he actually came over with one of his techs to look.  They had never tried what I described I was going to do but thought it might work.  Glad when something works out. 

I'll fix the epoxy problem one way or another. 

[Just Jim]

I'm in East TN also, when you get real good at this, You can do mine too.  LOL.  I'm in the camp of don't fix it.  I certainly fixed the leaks, but as far as the sides...  does not bother me at all.  On a 1995 model there is always something to work on.

 

[jacwjames]

You got that right, I took a 5 week trip and have been working on the coach +3 weeks to get it ready for the next trip. 

I had a leak during the trip but the delamination was from a previous leak in the same area.  I am actually removing all the caulk from the belt line and then will use Gelcel to reseal.  Also had to redo the gutter on the front windshield.  Had an electrical problem which I thought was the inverter but was actually one circuit, it would not let the generator run but the invert worked fine with it and it didn't kick the GFCI.  With this I made the decision to install a small secondary inverter to run the refrigerator and/or help charge batteries off generator.  Couple other minor problems I need to address.

It never seems to end.

[Chargerman]

Maybe try seeing if the epoxy manufacturer has a tech line and ask them for suggestions 

[rpasetto]

Outstanding work, Jim.

[Just Jim]

1 hour ago, jacwjames said:

You got that right, I took a 5 week trip and have been working on the coach +3 weeks to get it ready for the next trip. 

I had a leak during the trip but the delamination was from a previous leak in the same area.  I am actually removing all the caulk from the belt line and then will use Gelcel to reseal.  Also had to redo the gutter on the front windshield.  Had an electrical problem which I thought was the inverter but was actually one circuit, it would not let the generator run but the invert worked fine with it and it didn't kick the GFCI.  With this I made the decision to install a small secondary inverter to run the refrigerator and/or help charge batteries off generator.  Couple other minor problems I need to address.

It never seems to end.

Let me know if you need another set of hands.  I'm in West Knoxville so can't be to far from you.  I love the phrase that the only thing working 100% of the time on an RV is the owner.

[Guest Ray Davis]

Nice job Jim.     I don't envy the job of getting the epoxy off but you can do it.  Check into some Exacto knife blades, they may come in handy.

I agree with Ivan,  you need to do something about the corner points on the razor blades.   Grind them off, tape them, or something or they will eventually dig in.

I'm curious,  did you work from the window opening by pulling the fiberglass and injecting glue from there?   Or did you take the fiberglass loose at the belt lines?

Did you need to dry moisture from the area inside the wall,  and how did you go about drying it?

[jacwjames]

5 minutes ago, Ray Davis said:

Nice job Jim.     I don't envy the job of getting the epoxy off but you can do it.  Check into some Exacto knife blades, they may come in handy.

I agree with Ivan,  you need to do something about the corner points on the razor blades.   Grind them off, tape them, or something or they will eventually dig in.

I'm curious,  did you work from the window opening by pulling the fiberglass and injecting glue from there?   Or did you take the fiberglass loose at the belt lines?

Did you need to dry moisture from the area inside the wall,  and how did you go about drying it?

I pulled the beltline off hoping I might gain access to inject/place the epoxy but the way mine was constructed the wall is covered all the way around by the roof, rear, and bottom pieces and there was no way to gain access.  Most of the screws along the back and bottom were rusted off.   I removed all the metal molding that the beltline attached to .  Luckily I taped all the bottom portion and only had a minimal amount of epoxy leak out and it was on tape so easy to pull off. 

I was able to pull the fiberglass panel out far enough to gain access.  I did this at both the window and dryer vent hole. 

Initially I taped clear tubing to a  long dowel and/or flat 48" metal straight edge, that way I could get the tubing placed where it needed to be.  I bought some 150 ml syringes and used these on the lower pours.  Pushing the epoxy through the tubing with the syringes was not an easy task.   I tried to use smaller tubing but too hard to push resin through it.  I then started to use the copper tubing, this worked very well and I could rig up drink bottles to initially gravity feed the epoxy and in the end using air to inject the resin. 

Not sure how wet/moist the inside of the wall was, the parts I could see were dry.  I did have a couple pieces of the wood come off but was able to pull them out, didn't want them loose as they would cause bulges etc.

Good idea on grinding a radius on the corners of the razor blades.  As of now that seems to be the best approach.  Luckily I don't have that large of area and I can practice on the part that will be covered by the dryer vent. 

[Guest Ray Davis]

I guess the fiberglass is bonded to a thin wood veneer,  I have read that some walls are made that way.    Did the veneer stay attached to something and separate from the fiberglass?  Is that where you injected the glue,  between the fiberglass and veneer.    The wood pieces you pulled out,  were they pieces of veneer?    The info about not being able to pull the fiberglass away even with the beltline removed is very good info since at first glance that seems like the way you would go about it.          Thanks for posting and answering questions.

[jacwjames]

Most of the wood laminate stuck to the fiberglass, some stuck to the all. 

When I pulled the beltline and aluminum molding I was hoping that would give me access, it didn't.

But there's always more then one way to skin a cat, just had to figure it out.  Once I got into it I was beyond the point of turning back.  Lost some sleep trying to figure out way of getting the epoxy into the wall.  The last thing I tried was actually the best, quick, less messy.  I could move the copper tubing between mixes to get better coverage.  

BTW, I used about 1 gallon of the West Systems epoxy all together, most in the wall, some spilled, leaked.  Not sure what happen on one batch but it got very hot very fast and I had to abort!!!!

[Guest Ray Davis]

Ok, so most of the gluing was the wood to something behind it.      What was that something?    Sometimes I can see the wall frame work in the morning dew.     Is that framing something you had to contend with?

Sorry for asking so many questions

[Cubflyer]

Jim,

You always seem to be one project ahead of me!  My fiberglass below the drivers window is delaminated, badly, the wood paneling behind it is totally rotted away.  I have been thinking of doing the same kind of thing (use a piece of plywood as a form) and inject expanding foam behind the fiberglass hoping it would fill the void and create a firm surface attached to the fiberglass.  I never considered epoxy (I am familiar with West Systems product) and now I'm thinking about it... 

Great post! Thanks!

Ken 

[jacwjames]

When I spread the fiberglass from the window frame I did see a piece of stryofoam type material that appeared to be loose/moving.  

So I think the epoxy migrated to all the voids, hopefully adhering to anything and everything and when I pressed the fiberglass panel to the side of the motorhome it all bonded together.  Time will tell if the repair worked. 

The one thing I know is that epoxy will pretty much flow everywhere before it becomes viscous and sets up.  When I was building doors for my house I used epoxy to stiffen everything up.  I built 13 doors doors out of slabs of Sassafras.  Most of the slabs were good, some not so much.  So I'd tape the bottom side up and pour epoxy into any cracks and voids.  One door was ~44" wide and was pretty weak.  Did the epoxy and the door stiffened right up.  Here's a picture of on of the larger doors.

3 minutes ago, Cubflyer said:

Jim,

You always seem to be one project ahead of me!  My fiberglass below the drivers window is delaminated, badly, the wood paneling behind it is totally rotted away.  I have been thinking of doing the same kind of thing (use a piece of plywood as a form) and inject expanding foam behind the fiberglass hoping it would fill the void and create a firm surface attached to the fiberglass.  I never considered epoxy (I am familiar with West Systems product) and now I'm thinking about it... 

Great post! Thanks!

Ken 

I was considering using the Clear Gorilla glue but it sets up pretty fast. 

The West System slow cure hardener worked pretty good. 

In your case if you remove the window you should be able to inject the epoxy form above. 

When I took the beltline off and removed the aluminum molding.  I then mounted a piece of 2X4 using some of these screws.  https://www.lowes.com/pd/Teks-12-x-2-3-4-in-Phillips-Drive-Sheet-Metal-Screws-40-Count/3316526.

I could rest the plywood on this and then use 2X6/10 pieces top push against these horizontally.  Then another 2X4 vertical, using 2.5" screws to make sure I didn't screw into the fiberglass.  Used C-Clamps at the top to pull the vertical 2X4 pieces tight  to the horizontal pieces and plywood.  You can see this in a couple of the pictures. 

[Guest Ray Davis]

Some time back on IRV2 an rv tech commented that they use sheet aluminum when repairing delamination.   Attempts to ask him more about it went unanswered.          Guess he figured he had said enough,  maybe too much.   Anyway using wood seems to be the cause of delam along with water water of course.

Not sure I understand about the 2x4 and the beltline,  but you have been great sharing your project with us.   I learned a lot,  if I can remember it.😏

Edit----Went back and looked at the pictures again and now I understand about the 2x4

Edited August 20, 2021 by Ray Davis

[Cubflyer]

I used the Clear Gorilla glue to bond .040 301 Stainless Steel plates to the bottom of my bedroom slide where the rollers were starting to cut into the fiberglass bottom.  Worked great and now the slide travels in and out with lots less (fingernails on a chalkboard) sounds..... 

Good stuff, but something that flows and slow curing makes sense for the sidewall project.... 

We have another 4 week SLC/DEN trip to do, then it's flooring and delam project.... like someone said (I love it !):   'The only thing that always works on a motorhome is the OWNER'...

Ken

[jacwjames]

2 minutes ago, Ray Davis said:

Not sure I understand about the 2x4 and the beltline,  but you have been great sharing your project with us.   I learned a lot,  if I can remember it.😏

The 2X4's along the beltline simply gave me a shelf to work off off and then a mechanism to draw the vertical pieces tight to the side of the motorhome.  I figured out how to do it as I moved through the project.  When I moved up for the last injection I left the bottom 2X4 to attach support to.  If you look at the pictures it may help explain how I did it.