Luan Crack-Up

[calumet]

My Lowes 5.4mm Luan didn’t make the Benroy curves. Front and hatch both cracked. I have read where many were wondering. of course, your mileage may vary. There is no 1/8" Luan or plywood available in my area.

[mikeschn]

You need to get something that handles the curves... If you don't have it locally, you might want to consider getting something shipped to you. Boulter Plywood comes to mind.

Some other options include using aluminum or pebbled fiberglass for the roof. You'd have to paint the fiberglass with UV plastic paint. And for the inside get some moisture resistant paneling, backed with a masonite that can handle the bends. Another option is to use strips of wood on the inside.

There are other ideas... I'll let some of the other guys chip in.

Mike...

[madjack]

...one of the best ways to get ply to bend is to lay it on concrete(preferably), cover with towels and pour hot boiling water on it...bend the ply(when cool enough to handle) with a couple of straps and allow it to dry.....
madjack

[Lgboro]

Is exterior luan ok for use on a sandwich floor (luan x 1 by 2 frame and

insulation x luan) or would another wood be a better choice? I will travel to

find what I need if I can't find it in town. (I have 2 sheets of luan I want to

uitilize - hope this isn't off topic)

[Kens]

I used the same stuff on my benroy. I used lots of hot water, no cracks.

[Jim T]

Jack,
How long do you leave the water on it? Do you just leave the towels on long enough to cool down? I would like to use the 5mm luann available locally, but I am also having a bending vs breaking problem.
Thanks, Jim

[madjack]

...as the towels cool. add a second pouring of boiling water...when it cools enough to handle, take and bend the ply and allow to completely dry...a couple of straps work well for this...bend slightly more than needed and allow to stay that way till completely dry(I think I said that already)...boat builders use this technique to put compounds bends in ply...you can also apply the ply in place and attach temporarily, removing for final glue down when dry...you might wanna do this while the wife is away, since you will be taking all her towels out in the yard
madjack

[Jim T]

Much thanks! I was really concerned about that one!
Jim

[CASHCOW]

if you are going to skin the top can you not take a router and make 5 or 6 relief cut about 1" apert and 1/2 the thickness of the luan in the tightest part of the radius
http://s237.photobucket.com/albums/ff14 ... deview.jpg

[Toytaco2]

I understand your problem in trying to find 1/8 inch ply. In the Oklahoma City area I could only find it at one lumberyard. They had some luan which is not even 1/8" and staples blow right through it most of the time. The 1/8 birch they had seems to be pretty decent. I plan to put a layer of the luan on the roof first followed by a layer of the birch. So, my point is you can still have problems even if you find the 1/8 inch. "Boiled Luan" sound pretty tasty to me!

[bobhenry]

The best one I have heard is the use of a 5x10 square kiddy pool lined with black plastic to absorb the solar gain after water warms in the sun a few hours lay in the luan. Multiple sheets can be done together with dividing strips. Cover with more black plastic to retain heat and moisture and let them soak.

On another note ~~~~

Someone mentioned using fiber banding straps under the staples to keep them from blowing thru and easy removal later by lifting the strap and the staple will come with it.

[2bits]

If you haven't already done this, you might consider turning the sheets 90 degrees and having them bend with the grain horizontally. That's what I did and did not have to do anything special at all, (Modernaire profile). I used good 1/8" Birch, had to drive an hour to get it. Two sheets did my 5 foot wide tear. Two four foot sections on top, and I used the cutoffs to complete it in the very front, and the vertical joint of the small pieces will be behind a cabinet wall.

I have some 1/8" Luan I will be doing the exterior with, Hope it bends as easy.

[Jim T]

My problem is, that because I am trying to get as much height as I can as far forward as I can, I have a pretty tight curve on the upper front corner. The 5mm luann definately will not make the bend, and I am not sure about the 1/8". The water is probably going to be my best option. However, I LIKE the idea of the struts that run along with the curve! I may get this thing built despite myself!
Jim

[del]

I used 1/8th inch mahogany ply with out water, only one crack up. Yes it bends easier one way than the other (it cracked going the wrong way).


Curves yea my trailer has those.

del

[Miriam C.]

For those of you using 1/8 Birch outside make sure you get ply and not a panel. The panels look like they have 3 boards across.

1/8" Baltic Birch bends really well too as do door skins.