What alternatives to 1/8 plywood?

[Aaron Coffee]

What alternatives are there to using 1/8 plywood for the roof covering? I am planning on using aluminum over it. I looked around at lumber yards and box stores on my first build, they didn't have it or couldn't/wouldn't get it(due to the fact that they had to buy a whole pallet at a time. Ended up using masonite, I see where it is starting to come apart in a few places where it is exposed at the hatch. Can masonite be sealed with epoxy? The guy I bought the 1/2 plywood from does cabinetry and said that my best bet was to find a cabinet person that using it and has some or is ordering some. Have a couple of cabinet guys that I know that I will check with.

[planovet]

I'll second asking the cabinet people. I got my 1/8" birch ply from a specialty wood shop that caters to that market. The big box stores will never carry it due to lack of demand. That being said, many on this board have just put the aluminum over the spars with no wood underlayment (ask Madjack). Good luck.

[madjack]

I too, use cabinet shops for better access to harder to find plywood...also after reviewing techniques for building, including those used by Camp-Inn and KuffleCreek I applied the .040 AL sheet directly to the spars of the current build and have had no problems doing so and would/will do it thataway again.........
madjack

p.s. if you can't find but really want 1/8th ply, try looking at the paneling available at the box stores...I have found 1/8th paneling at the box stores which was a Luan ply with a birch veneer...you can even find it with a good looking Luan side for under 20bux a sheet...the only downside to using this product is the birch veneer side has a finish on it that will keep some adhesives from sticking to it...a good sanding will fix that problem........MJ

[Darren]

I'm sure someone will say not to, but, I used cheap interior paneling. I only used it on the roof and then covered it with urethane. Once that set up I covered that with upholstery vinyl. The paneling was very flimsy so it made it really easy to get around the curves.

I did some testing with the paneling and let it sit in water for a couple of days, it didn't absorb any water. It's held up for 3 years but I keep it in the garage when not camping.

When I was researching my build there was a thread on what materials to use and basically an argument about what not to use. Someone made the comment that you can use cardboard if you want. Just make sure it's all sealed and can't get wet. Hope that helps.

[goldcoop]

Tempered Hardboard

Cheers,

Coop

[len19070]

Masonite

[kennyrayandersen]

Yeah, you CAN use anything, but if the ‘plan’ breaks down, the consequences are not all the same. If water gets to MDF, particle, board, or most of the other pressed products, my guess is that you would at a minimum get a bunch of swelling and whatnot, which might be more difficult to repair. Even the Luan, which will work, but there have been some pictures posted where when a bit of water gets in it can do a fair amount of damage.

If you are going with Al anyway, I kind of like mad Jack’s concept of using the outer Al as the structural member. Hardly any thickness added to the minimum Al required to resist dings will be robust enough to be the primary, and really only piece on the exterior. If you are not going with Al then I’m still a fan of a something to make sure the exterior paint will maintain its integrity (layer of thin fiberglass, rubber or vinyl coating as some have done). Seems to me that moisture appears to be enemy number 1 regardless of the material chosen.

[48Rob]

Kenny wrote;
Seems to me that moisture appears to be enemy number 1 regardless of the material chosen.

Aaron,

If your hardboard (masonite) is "coming apart" you haven't got it sealed, or sealed well enough.

No offense, but most people that don't build things that must resist the weather, don't fully understand how important it is to make sure NO weather can get to any raw wood, or wood product.
Just a very small area can wick up a lot of moisture.
Sealing wood is good, but one or two coats may not (usually IS not) enough to fully seal the surface.

As Jack suggested, using aluminum directly over the roof supports is fine, as long as it is thick enough to resist sagging and denting.
A lot of people that use paneling under the aluminum don't "need to" for support, but choose to for appearance.
Staring up at a cold exposed aluminum sheet can be unattractive to some...

As also suggested, the cheap big box store "paneling" in 1/8" can be used for "looks" (facing the interior) with the aluminum on top.

Be SURE the cheap paneling is real plywood, and not particle board...
(look at the backside, if it is plywood, it will look like real wood, and will be lightweight, particle board/pressed board is very heavy)


Rob

[madjack]

Kenny wrote;
Seems to me that moisture appears to be enemy number 1 regardless of the material chosen.

Aaron,

If your hardboard (masonite) is "coming apart" you haven't got it sealed, or sealed well enough.

No offense, but most people that don't build things that must resist the weather, don't fully understand how important it is to make sure NO weather can get to any raw wood, or wood product.
Just a very small area can wick up a lot of moisture.
Sealing wood is good, but one or two coats may not (usually IS not) enough to fully seal the surface.

...to completely seal wood product REGARDLESS OF PRODUCT USED you will need to do a minimum of 3 coats..the first, will be full of both microscopic and larger air bubbles and voids from evaporating aromatics...the second coat will fill most of the air bubbles and voids but still leave some...the third will pretty well finish up the seal, a fourth, if you have extra product won't hurt...

As Jack suggested, using aluminum directly over the roof supports is fine, as long as it is thick enough to resist sagging and denting.

...use at least .040, we put our spars at 9" centers and put some cross blocking in as well.....


A lot of people that use paneling under the aluminum don't "need to" for support, but choose to for appearance.
Staring up at a cold exposed aluminum sheet can be unattractive to some...

As also suggested, the cheap big box store "paneling" in 1/8" can be used for "looks" (facing the interior) with the aluminum on top.

Be SURE the cheap paneling is real plywood, and not particle board...

...DOUBLE AMEN +10 to that!!!!
(look at the backside, if it is plywood, it will look like real wood, and will be lightweight, particle board/pressed board is very heavy)


Rob

madjack

[RichAFix]

I can't believe a lumber yard can't/won't get you a few sheets of anything. It may cost a bit more but I can't believe that they would have to buy an entire pallet. Maybe I am just spoiled? My (not too local, about 40 miles away, but a cousin of a friend) lumber yard told me that he can order anything by the sheet. It takes about a week, and I am sure it isn't the least expensive, but I got .25" birch, .125" birch plywood, and I know he doesn't keep pallets of the stuff laying around.

Try a different lumberyard.

Good quality is hard to achieve (not impossible, but definitely more work) without quality materials. Thats just my opinion. I have found that the right materials aren't really that much more expensive than a cheaper alternative, and usually less work.

[Aaron Coffee]

when I was building #1 I had read somehwere about telegraphing, where from wind force the aluminum would bend somewhat and show every spar. I have seen this on walk in toolboxes wuilt on racecar trailers. But they are usualy 6 foot flat walls, with aluminum mounted directly over a framework of square steel tubing. And yes #1 isn't sealed very good, I hadn't yet found this forum and the Desert Teardrop plans (as I now know) are sketchy, but live and learn.

[Mini Renegade]

not that is close to you guys but I found my local independant timber suppliers were really helpfull when I went in with my list. They even ordered in 2 8x4 sheets of 1/4" flexible ply for me with no probs.