Foam to fiberglass glue

[ogrer]

I had a leak and water accumulated under one side of the Bigfoot, in the overhang, over the side walls of the truck box.

The foam is saturated with water and the plywood backing panels for the tie downs are rotten.

So, I have removed all of the kitchenette and floor. I have taken out the furnace and water heater.

I need to replace the foam and the plywood backing panels.

My question is what is the best glue to fix the foam to the fiberglass. I am also thinking of blue foam over Styrofoam.

I still have to find the leak before I close it back in.

Bob

[ogrer]

Is it hard to pull the windows? I would like to do them too.:)

[ogrer]

On the same repair, the water heater was pulled, to do the repair.

When it was out I noticed three types of caulking?

1. White Proflex on the outside
2. Grey Butyl tape on the mounting bezel
3. Looks like Clear Silicone on the bezel to heater frame.

The bezel looks like a crimped on stamping.

The heater is cleaned and painted, ready to go in, when I find out what is the third caulking.

The third caulking was not in good shape, and also was used the seal the folded corners of the water heater frame.

I am thinking this could have been my water source.

Bob

[Reddog1]

I strongly suggest you pull and re butyl tape all windows, making sure the tape goes over the edge of the frame and trim the excess after window frame screws are tightened. Trim excess with a plastic knife or something similar. If done correctly, you will probably have the tape oozing out for a couple of years. Do not put any type of calk around the windows, tape only.

[ogrer]

Thanks for the replies.

I have gone shopping, bought some pressure treated 1" deck boards, pink foam, glue, contact cement , butyl tape, proflex caulking and some fir plywood

The plan is to use gorilla glue to fasten 1X2 on 16" centers for the connection to the bottom of the over hang. That will give me something to screw the floor to, and will also provide additional support through the area.

I picked up water soluble contact cement, and I will use this to glue the "pink" foam in.

We have thoroughly soak the camper and have not found any leaks.

Bigfoot left a space along the corner, about 1" X 1", it looks like a path to along any leakage or condensation, my guess it is a way for the water to drain out to the drain holes in the rear.

I have to get the unit back together, as we are heading out, mid June for Alaska's Kenai. If you have been there you know it rains almost every day in the summer.

Again thanks for the replies.

Bob

[Jack_Spratt]

Look in Home Depot/Lowes there is a cartridge adhesive specifically made for use with foam.

[covered_wagon]

When I reset my windows I usually double the putty tape and screw the interior pressure trim ring slowly allowing the putty to flow over all mating surfaces s allowing an even squeeze out of putty. Better to do this on warm days as the putty tape flows better.

BTW, my NL camper now has the cabover stress point bulges very small on both sides that are talked about in the above link. It started last winter. I'm going to leave it for now to watch it grow, if they do. I think mine was repaired in the past when new because it does have plywood reinforcing behind the glass unlike others who say they do not.

An interesting note; one side was bulging much worse when used fulltime last winter, but has now shrunk in size to match the other side and are now very small.:h

[mydazeoff]

I have used 3M Fastbond Contact Adhesive 30-nf to make similar repair. Purchased at Amazon.com. You should be able to find the data sheet on the 3M website.

[Reddog1]

[Joe417]

I've tried a lot of different types of adhesive and have found polyurethane to be the most consistent in bonding skins back on. Moisture cured works fast. It bonds to wood, foam, and aluminum.

It also expands and fills cracks between the surfaces. So, if you use it, be sure to clamp the surfaces to prevent them from expanding more than you want.

Gorilla Glue is readily available.

[Reddog1]

Fortunately I have not needed to glue the fiberglass on my TC. I would use the blue foam.

This link, Two Northern Lites with Cab over failing and Basement sides, might offer some help.

I would do a test section using Gorilla glue. It is available at most hardware stores. I would not use silicon.

For locating the leak, my first guess would be the weep holes in the window frames. They get plugged and can let water in the TC. Another place is the seal between the window frame and fiberglass.

Every TC I have owned has had window leaks at some time. I have had to rebuild the wood inside the walls in three TCs due to the window leaks. On my 1988 Bigfoot (see photo), I use butyl tape only (sticky on both sides-see photo), and absolutely no silicone. That is what was used by the manufacture, and did just fine for twenty years. The butyl tape is common at RV Supply stores, and I have heard it is available at Home Depot in the caulk area of the store.

I am having issues posting with photos. I will try separating the photos from the post.

[covered_wagon]

I agree a good polyeurethane adhesive caulk would be great if applied with beads 1/2 inch apart. That would be a no nonsense way of doing it.

[silversand]

Polyurethanes are interesting, however, also have a look at XPS grades in the 600 type VII to 1000 psi type V strength grade (no kidding; these panels are nearly like plywood). I think the Formular brand (Owens Corning?) are readily available. Do your due diligence with all the products out there.

*disclosure: I do not work for, nor own any position in any foam manufacturing industry

[Kayteg1]

Exterior construction glue in caulk will work as well, but that thing needs days to dry.
If you are replacing insulation, think about upgrading to polyurethane.
Not only R value is about 15% higher, but much stronger mechanically.

[silversand]

Beadboard (usually white, with little beads bound together) is EPS. Extruded polystyrene (blue, pink, etc) is XPS.

You need to do some serious research into using either EPS or XPS as a SIP (in this case, the structure is the wall/camper shell). There are very specific adhesives you can apply (with a paint roller, mop, or, via spray gun) to bond the EPS or XPS...some of the adhesives go on quite thick, and can bridge "bowing" in camper structure shells, but, if you press (roll the SIP assembly with the glue sandwich) or vacuum-bond the structural panel, the adhesive will ooze out along the wall's edge. Some of the adhesive used in making Our Outfitter Mfg XPS-to-FRP structural walls oozed out during the vacuum bonding stage, and dried a 1/4 inch thick (probably much thicker than a silicon bead!).

Good luck.

On the edit: i changed the word "bowling" to "bowing".

[HMS_Beagle]

Bigfoot uses a spray contact adhesive. You want something that is somewhat resistant to softening with heat, and with solvents that do not melt the foam. Given that there is probably residual contact adhesive on the fiberglass, using the same type of product might be advisable as other things may not stick well to it. Silicone would be near the bottom of my list, it is not a very strong adhesive and yet will be hard to clean out it if comes loose, nothing at all stick to it. When boatbuilders use foam core, they will mix polyester of epoxy with fillers to thicken it, then use a notch trowel to apply.

Blue foam (extruded polystyrene) is a better choice for a core material than bead board (expanded polystyrene). I don't know why Bigfoot changed - XPS is less expensive I guess.