Particle Board?

[Sam]

My camper has water damage on the outside under the cab-over bed portion. It looks like condensation forms in this area or rainwater "clings" here and never really gets a chance to dry out (mostly when you keep the camper on the truck full time?)

It looks easy enough to replace this section but what I found strange is that particle board is used in this area. Did the older campers come this way from the factory, do the new campers use particle board? What was FWC thinking (Ben/Marty)? and does anyone else have this problem or am I just the lucky one?

Thanks,
Sam

 

[marty]

Partical board

Sam,
Fwc did use melamine for the bed board for many many years and while Ben owned it Ben actually upgraded that board to a vinyl clad board that was not particle board. The moisture more than likely came from inside. How old is your camper ? It looks to be an upper 80's model. When you change that bed board my only real tip would be to use lots of silicone even on the edge area.
We do not use that type of wood here at atc however if your camper is almost 20 years old or so i would hope that more melamine would last another 20 years if it was sealed real good. We would be happy to assist you or walk you through the repair. And another simple way to make it bullet proof would be to Formica or Formica type plywood or simply paint a good 3/4 inch plywood.

Marty

 

[Sam]

Marty,

Thanks for the info. I was going to do plywood with a Formica lamnate, is that what you are using on the ATC? Also you say it looks like my damage is from inside? I see no sign of water damage under the matress. I did notice that when I washed the camper the water seemed to all collect on the one spot where the damage is. I think that the melamine has been sagging in the center and so any moisture/water collected in this one spot.

You are correct the camper is an 89 and the melamine did last all these years, but if I were building the camper in 89 I would not have used this material. When you use particle board you can gurantee that it will fall victim to water damage at some point.

Sam.

 

[benburnett]

damaged bed board

Sam,

You are probably correct as to how the damage was created. You have one of the last years that the bed board was made from that material. The previous owner to me of FWC changed the bed board to a vinyl clad wood that we continued to use while I owned the company.

A Formica covered wood will work great for you and will never wear out.

Sincerely,

Ben
www.allterraincampers.com

 

[WarpathEngineering]

Ben & Marty,

Is the material your using for the bedding board called FRP Plywood? I'm in the process of replacing mine.....a lot of rot! I was going to use marine grade but in researching it, it seems that the only thing that makes marine grade different form regular old exterior grade is the lack of voids in the plies not rot resistant wood. Hoping only to do this once and since I live in humidity city..... I had a line on a sheet of 3/16 diamond plate aluminum but the scrap yard had already scrapped it by the time I got there.

 

[benburnett]

bed board

The wood that we are currently using for the bed board is a vinyl clad wood. The description from our invoice is as follows:

3/4 w/2/s plycore 4 x 8

A better lumber yard should be able to get you a vinyl clad wood similar to what we use. Let me know if you any problems finding it and I may be able to locate someone in your area that has it or can get it for you.

 

[WarpathEngineering]

Thanks for the info Ben. I looked around yesterday for the vinyl coated plywood but no luck. I went ahead and bought a sheet of MDO plywood. What do you think.....Paint or Formica?

By the way, is there an easy way to reinstall the plywood? My old sheet was pretty well rotten, infact in a couple of places a hammer blow took out some coffee can sections. If I'm looking at the engineering right, it looks as if the plywood is installed before the back is welded on the camper. I'm installing a 4" drop to mine so I'll probably have to put the plywood in before the welding is complete. I'll post pictures...that is if I remember to take them in the first place!

Rick

 

[benburnett]

bed board

Paint should work just fine. Just a decent exterior paint works great on the floor packs, there is no reason it would not work on the bed board. Formica would give you a smoother surface of course and would probably look better but painting it should make it last just as long.

Since you are customizing your camper you might see an easy way to put the bed board in. We put it in before we weld the front together on a new camper. If we have to replace one on a camper that is already built, we actually take the bottom of the side liner loose on one side and slip the bed board in from the outside. We cut it 1/4" smaller than the original so that it will slip into position through the liner.

 

[Coop]

Particle Board

Sam.
Some thoughts and observations regarding water damage to the cab-over
bed board. I have an older camper, circa late 80's. My cab over board is particle board, gray primed inside, with some kind of white vinyl or plastic cladding on the outside that BenBurnett alluded to. I caught the start of the water damage early and was able to take remedial action to prevent any further damage from taking place without having to remove/replace the original board. It's held up fine since for over 20 years! Based on my observations at the time. Melamine or any Vinyl clad board, be it on one side or both (both being the worst case) is the absolute "wrong/worst" material to use in any wet, damp or moist environment...period! The main reason being...it cannot breath. So...if it does take on moisture for any reason it cannot dry out, the moisture/water remains trapped inside indefinitely. Consequently, it rots from the inside out! And you don't know it until the cladding starts to swell, bulge, sag. Obviously, since water/moisture/condensation cannot enter through the Melamine or Vinyl cladding, unless it's surface integrity has been damaged, the only "logical" access is along the exposed/sawed edges of the board. From there it can seep, wick, or by capillary action, migrate anywhere within the inner particle board. I believe there are two sources contributing to moisture entering the edges of the board. One...obviously from the outside. Seeping in and behind the trim stripping, wicking up between the inside surface of the outer aluminum paneling and the exposed inner edge of the bed board. And...even seeping/wicking in past the myriad of screws that hold the trim stripping in place. I know when I removed the screws in my rig, many of them were...rusty!
The...second...and far less obvious/apparent source is on the inside!
I found on many occasions that the inside surface of the deep aluminum channel that makes up the front surround of the camper, at least the 3,4 or more inches of it that extends up above the bed board top surface, to be absolutely running wet with early morning condensation. That condensation can collect and run right down between the surface it's on the exposed edge of the bed board that buts right up against it!
IF you have to replace your board, start by using marine grade plywood. With all due respect to Warpath Engineering, he is mistaken or has been ill-informed! Everything about "marine" grade plywood, in addition to no interior voids, has been developed for it to survive in "wet" environments! The adhesives, wood selection, lamination process, everything! That's why they build boats out of it? Seal it with marine grade varnish or paint before you install it. Especially the "edges”. Then...as you install the board, at every/and any interface surface spread liberally and seal with a good latex (water clean up type) sealant. (Coat the entire surfaces as they go together, don't just assembly then run beads along joints or edges.) Inject sealant into each screw hole to seal off all/any screws as you install them. Then finally, run an additional raised sealant bead (there should already be sealant between the two surfaces) around the inside where the bed board buts up to the aluminum channel skin. This will doubly insure that moisture at least can't collect right along that joint. And you should mop it dry any time conditions are such that condensation can occur there.
A lot of work...sure! But, depends on how long you plan on keeping your camper, and having ...no worries mate!

Coop

 

[benburnett]

Bed Board

Coop,

Excellent post on the bed board and explanation about the wood. You are right in every way.

One thing that I have noticed though over the years is that the older particle board beds did have a habit of coming apart over time. When we switched over to the vinyl clad wood, it doesn't seem to suffer from the effects that you point out. I am not saying that it won't, just that I have never had to replace one of the vinyl clad bed boards that were made of real wood instead of the particle board. At least to date we have never had one returned for damage the way the old ones used to come in.

Most of the reason that I think the new beds have held up over the years so well is the fact that we do seal them when we are building the camper.

Who knows though, we might see the same type of damage in 15 or 20 years compared to the 7 or 8 that the old beds seemed to go bad in. A lot had to do with the care of the older campers also. Most of the damaged ones I saw that came in were second hand and had been sitting for some time without any care or use.

Not trying to take anything away from your post though. Again, I agree with you 100% on your logic and experience with wood.

 

[WarpathEngineering]

Just to put my two cents worth in......In my research, and I have the tendency to do a lot, I made note that marine grade plywood uses essentially the same exterior grade of wood and waterproof glues in its laminations as what is used in house building plywood sheeting also known as CDX. This is not a bad thing! What makes marine grade plywood a superior product to regular building sheeting is the lack of voids in the interior plies and the increase in the number of plies. Both of these lend an incredable strength to marine grade plywood.

The product that I decided to use, MDO or Medium Density Overlay, is marine grade plywood with a resin fiber material applied to both faces to provide a smooth easy to paint surface. This material is commonly used on building exteriors, porch areas, exterior signs as well as boat construction. They also make two other types of plywood that I would have been interested in looking at but was unable to find in my area, FRP & HDO.

HDO, or High Density Overlay is manufactured with a theromsetting resin impregnated fiber surface bonded to the outer plies under heat and pressure and is made to withstand the most trying weather situations.

FRP, or Fiberglass Reinforced Plastic as the name implies has a layer of fiberglass reinforced plastic adheared to both faces. This product is commonly used as the side panels on delivery trucks and trailers. It is both lighter and stronger for it's weight than steel or aluminum.

 

[Coop]

Particle Board and Marine Ply

Hello Warpath.

With regard to my earlier comments on "Marine-grade" plywood, I stand corrected
on one important point. The "adhesives" used in Marine-grade ply and quality Exterior-
grade construction plywood are the...same. And they are, of course, waterproof, as opposed to
water or weather resistant. As you have noted.
By all other spec's , one of which is the permitted use of only two species of wood, Fir and Larch,
at least for American produced Marine plywood, it remains the only grade plywood specified for boat
building and the marine, i.e. prolonged "wet" environment. Not that you can't use anything else
I guess, just depends on how long you want... your boat to float!! Aye?
However, I would respectfully still like to offer some comments regarding the perceptions
surrounding CDX plywood.
As I'm sure you are aware, a common misconception in grading plywood is that the"X" designates
an "Exterior" rating. It does not. What the "X" designates is that the inner veneers/core of the board
can be of any species of wood. So that rules out any possibility of a "Marine" grade rating for CDX.
The C & D, as you will be aware, designate the finish/quality of the outermost veneer/ply on each side
of the board. The ratings being: A, B, C & D. With A being the finest/cleanest and D being the roughest,
coarsest, knottiest, ugliest, cheapest. CDX therefore can be made of any type wood the Mfg' chooses,
and... the C side will have a somewhat better finish/appearance than the roughest D side.
CDX is not an "Exterior" rated ply. It is an “Exposure” rated grade. In that it has the ability to withstand
exposure to exterior conditions for a “short time only” while a building is under construction.
But for the long term it is an "Interior" grade and is recommended only be used inside a building where it is
protected from any long term exposure to moisture/water/dampness, the elements.
One of it's biggest uses is as interior sub-flooring because it's super strong, but...cheap.
And the...ugly...gets covered up!
OSD Plywood (Oriented Strand Board) is, or is becoming, the "Exterior" grade of choice now in
construction. It is being used for exterior walls, roofing and general coverings, being considered highly
impervious to moisture and the elements. So in retrospect, or...hindsight ?? It would probably be a very
good, if not the best, lower cost alternative to Marine grade ply for replacing the cab-over bed boards in
our campers. Not withstanding the liberal use of latex sealants, good paint/varnish etc. when doing the job.

Also, MDO, by definition, is not a...Marine grade plywood. Marine grade plywood can have a
Medium Density Overlay of the "resin impregnated fiber material" you describe, but...so can
any other grade of plywood. MDO itself is a "secondary stage of manufacturing, or finish"
applied to any common veneer/ply substrate, which then becomes a...Medium Density Overlay
Plywood (MDOP). They've gone and dropped the "P", which now confuses the "finished product"
with the...process!

I guess if this were a boat building forum this would all have far more relevance...huh? HA!
At the end of the day though, I guess the whole point here boils down to, that for anyone considering
the replacement of their bed board, give serious consideration to using ... OSD Plywood!

Regards...CoopCoyote