Montana 5th wheel fire damage repair with pics
got a crispy camper from insurance co with rear wall damage from a fire. my first foray into filon fiberglass repair as I'm a mechanic and not a body or fiberglass guy by any means. Hopefully this helps you brave do-it-yourselfers out there. The job wasn't too bad but if involved. After being quoted over $8000 for repairs I fixed it on my own for a few hundred bucks in materials, and some help from a couple friends. You will need it to hold the wall up while putting in screws for the trim pieces. The construction of the wall is simple and is just filon fiberglass bonded to 1/4" plywood. A main challenge is that the wall was about 8'6" tall by 100" wide. No problem on the width part as filon comes in a roll about 104" wide. However, you won't find plywood in sheets larger than the standard 4x8 so we decided to piece together 3sheets widthwise and butt them up against one another. I don't like seams, but we had no choice without the ability to get a huge piece of plywood. We bought the filon from rvpartsnation.com (formerly rvsurplussalvage.com) as they had the best price at about $23 per running foot. Shipping isn't cheap and is over $100 due to being oversized, although light in weight. It pays to check around as all-rite wanted $66 per foot which is insane. Now on to the proper adhesive to bond the filon to the plywood. After doing research I found that Sta-bond had many good reviews, but was also hard to procure and was expensive. So a trip to the orange box was in order to get some Dap contact adhesive. Some folks use the 3m version as well. It was $29 per gallon and more than enough the do the rear wall and slideout wall as well, which was also quite crispy.
removal was pretty easy and consists of removing the 4 trim pieces around the rear wall and umpteen million screws that will be square drive, the standard choice of rv builders for some reason. After removing the ladder, windows, and the melted tail lights, it literally fell down and folded over on itself, bopping me on the head in the process. Good thing cooked 1/4" plywood isn't too heavy. I was surprised to learn it didn't have foam block insulation adhered to the plywood, rather it was regular fiberglass insulation which most of it was still in good shape, and the interior walls and aluminum framing were not damaged. Another bonus. As for the rear slideout wall, it came off in a similar fashion. one good thing was that after the rear wall windows were removed, this gave me access to the very inside portion of the slide through the window hole so I could get to the normally hard to reach screws. HAHA TO THE RV REPAIRMAN WHO SAID THE SLIDE HAD TO BE REMOVED TO FIX THAT.
OK so now to repair the damage with a new wall: we laid the filon down and rolled it out and let it sit in the sun a few hours to flatten out.. then cut a piece a little larger than what we needed to make things easier. you don't want to cut it too small in case you have to make adjustments down the road. after laying the filon down in the garage we then cut the plywood to size. Due to being about 8 ft 6 inches tall, we basically ended up with a short, curved 6" piece art the top which can be seen when viewing the new wall, but it doesn't bother me. I saved 8 grand so even if not totally perfect, all worked well in the end. We cleaned the filon with denatured alcohol so it would have a clean surface, then rolled the contact adhesive onto both the filon and plywood using a short nap roller. wait about 20 minutes before putting the pieces together. Then me and my buddy stepped all over the pieces for a few minutes to try and get all air bubbles out as best we could since no access to a roller (boy is this guy shadetree or what?) To ensure good dry time we then used several concrete landscape pavers as weights on the whole thing, especially on seams and corners, and let it sit a few days. Ideally contact adhesive should be applied when a minimum of 65 degrees or hotter, but it was about 55 when we did it.
after drying, we used the old crispy wall as a template and traced the outline all the way around, then did the cutouts for windows and lights, as well as the shore power cord. We used a jigsaw with multiple small teeth to cut the outline and windows, and a hole saw for the light holes and power cord. Then all that was left was to raise it into position, which is a 3-4 guy job. Couple guys holding the wall in place while I scurried on the roof to start dring screws into the trim piece on the roof. once wall was into position and a few screws driven, we used clamps to hold the wall in place through the window cutouts, clamping onto the aluminum frame. The top and bottom trim pieces go on first, followed by the vertical side trim pieces. i insisted on dipping each screw in proflex sealant before installing it. This results in much less chance of water wicking in through a bare screw. Pretty much every rv I've ever worked on has several rusty screws from water getting in, and after doing this fairly extensive work i wasn't about to let one of a million screws start a cancer of water damage in an otherwise nice 5th wheel. the job was finished off with new dicro roof sealer and eternabond on the roof seam, as well as sealer on every joint or side seam we worked on. just got new slide seals and replacement cable outlet in the mail. those were melted also. new decal in place and she's ready for the road!
removal was pretty easy and consists of removing the 4 trim pieces around the rear wall and umpteen million screws that will be square drive, the standard choice of rv builders for some reason. After removing the ladder, windows, and the melted tail lights, it literally fell down and folded over on itself, bopping me on the head in the process. Good thing cooked 1/4" plywood isn't too heavy. I was surprised to learn it didn't have foam block insulation adhered to the plywood, rather it was regular fiberglass insulation which most of it was still in good shape, and the interior walls and aluminum framing were not damaged. Another bonus. As for the rear slideout wall, it came off in a similar fashion. one good thing was that after the rear wall windows were removed, this gave me access to the very inside portion of the slide through the window hole so I could get to the normally hard to reach screws. HAHA TO THE RV REPAIRMAN WHO SAID THE SLIDE HAD TO BE REMOVED TO FIX THAT.
OK so now to repair the damage with a new wall: we laid the filon down and rolled it out and let it sit in the sun a few hours to flatten out.. then cut a piece a little larger than what we needed to make things easier. you don't want to cut it too small in case you have to make adjustments down the road. after laying the filon down in the garage we then cut the plywood to size. Due to being about 8 ft 6 inches tall, we basically ended up with a short, curved 6" piece art the top which can be seen when viewing the new wall, but it doesn't bother me. I saved 8 grand so even if not totally perfect, all worked well in the end. We cleaned the filon with denatured alcohol so it would have a clean surface, then rolled the contact adhesive onto both the filon and plywood using a short nap roller. wait about 20 minutes before putting the pieces together. Then me and my buddy stepped all over the pieces for a few minutes to try and get all air bubbles out as best we could since no access to a roller (boy is this guy shadetree or what?) To ensure good dry time we then used several concrete landscape pavers as weights on the whole thing, especially on seams and corners, and let it sit a few days. Ideally contact adhesive should be applied when a minimum of 65 degrees or hotter, but it was about 55 when we did it.
after drying, we used the old crispy wall as a template and traced the outline all the way around, then did the cutouts for windows and lights, as well as the shore power cord. We used a jigsaw with multiple small teeth to cut the outline and windows, and a hole saw for the light holes and power cord. Then all that was left was to raise it into position, which is a 3-4 guy job. Couple guys holding the wall in place while I scurried on the roof to start dring screws into the trim piece on the roof. once wall was into position and a few screws driven, we used clamps to hold the wall in place through the window cutouts, clamping onto the aluminum frame. The top and bottom trim pieces go on first, followed by the vertical side trim pieces. i insisted on dipping each screw in proflex sealant before installing it. This results in much less chance of water wicking in through a bare screw. Pretty much every rv I've ever worked on has several rusty screws from water getting in, and after doing this fairly extensive work i wasn't about to let one of a million screws start a cancer of water damage in an otherwise nice 5th wheel. the job was finished off with new dicro roof sealer and eternabond on the roof seam, as well as sealer on every joint or side seam we worked on. just got new slide seals and replacement cable outlet in the mail. those were melted also. new decal in place and she's ready for the road!
