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Lauan Bubbles

PostPosted: Sun Oct 26, 2008 9:09 am
by Spotman
I did some searching, but to no avail. Thought I would throw this out to the experts. I haven't had the chance to use the "cabin" anytime this year, because of hectic work schedules and other things.

My question: The paneling is starting to bubble in various spots all around the camper, is this because it was uncovered all year? It was only coated in two coats of oil base paint when it was completed two years ago. After reading a lot of info on here from all the great builders, something tells me I should have coated it with something else!

Any suggestions from you all would be appreciated. How do I fix this problem without having to cover it entirely with the so called "bed liner" stuff?


Thanx,
Bob :?

PostPosted: Sun Oct 26, 2008 10:49 am
by 48Rob
Hi Bob,

Using oil based paint to protect your plywood was not/is not, a bad idea, nor the cause of your troubles.

Moisture is.

You didn't say if the bubbles are in the paint, or in the plywood, but either way, moisture is causing the bubbles.

It could be getting in through the edges of the plywood, a window or door cutout that didn't get any/enough sealer/paint, or it could be migrating from the other side of the plywood.

It could also be a case of two coats of paint not being enough to completely seal the surface.
I have no idea how you painted the wood, and mean no offense, but most people do a fantastic job at painting/sealing/varnishing that which is visible, but pay very little, or no attention the cutouts, edges, and the reverse side of a given project.

The type of wood, and which side makes a difference too.
Some species of wood can be properly sealed with two coats of oil based paint, some can't.

Plywood for example, can sometimes be sealed well on the face with 2-4 coats, but the edges, or endgrain may take 8 to attain the came level of moisture protection.

Can you provide more information, and or pictures of the bad areas?

Rob

PostPosted: Sun Oct 26, 2008 2:20 pm
by Spotman
Rob;
Thanks for the reply, I added some photos today in my album. As you can see in some photos, I have "L" borders (Trim) on everything and sealed with caulking!

After I get it fixed, I will be making a cover for it!!

Bob

PostPosted: Sun Oct 26, 2008 3:41 pm
by Juneaudave
Ya know Bob...I'm wondering if luan is really appropriate for an outside skin. I know it has been used successfully for many builds, but I wonder if there is a "quality" issue that makes some luan better than others. Some of your bubbles are in the middle of the sheet...edges I understand...That's a tough fix!!!

:thinking: :thinking: :thinking: :thinking:

PostPosted: Sun Oct 26, 2008 10:08 pm
by doug hodder
Bob...not to be MR. Negative, but I personally think you could be in store for more spots in the future. I could be wrong and hope that I am, but as Rob said, moisture is what caused it to lift, it appears that the veneer has lifted from the core. I found that Luan is a poor choice for an exterior material. I've done it. I'll never do it again, and I buried mine in multiple coats of epoxy to prevent that very issue. My problem was that it wouldn't bend like I wanted it to and actually cracked like 6" long. I don't have any bubbles, but can tell, it's not as nice as using a higher grade material.

As mentioned, all the edges must be sealed completely. I think that any raw edge especially in a luan, unless sealed with something like CPES or epoxy will only allow water to wick into the material. Luan is not made for exterior uses, and as far as I'm concerned, is only suitable for templates, it's the AntiChrist!

When you push on the bubbles, can you make the material lay completely flat? Just an idea, but you might try drilling several tiny holes, injecting some good water proof glue in with a syringe at various angles and backing it with a board and some sort of weight or brace against the side or roof area and trying to get it to bond again. You might also want to open up a bubble, (slit it with a razor) and see if there is any mold in there. If the exterior veneer has lifted, there may be other issues with the core. It's not usually as good as the exterior. Others opinions may vary.
Sorry to hear of your problem. Doug

PostPosted: Sun Oct 26, 2008 10:43 pm
by Micro469
I have Luan on the side of my trailer and so far have no problem with it. I did cover it with 3 coats of CPES, and then epoxy. I also have Baltic birch on my roof,and it did bubble around my vent. What I did was cut an H throgh the bubble, very carefully peel the pieces back while I shoved as much epoxy under it as I could. Then I put some wax paper on it and weighed it down. A little hard to do on the sides, but it worked for me......

:cry: ;)

PostPosted: Mon Oct 27, 2008 7:35 am
by bobhenry
As usual you guys hit it right on the head. I am faced with the same problems with Chubby. I veneered a layer of 1/4 " Luan over the osb sub siding. My sheets run vertical so there are 2 seams on each side.
Dark discoloration is starting at the seams and around the door. While I applied 7 coats of marine spar varnish I failed to seal the seams 1st and did not back and edge treat the doors as they are not finished yet. ( May never be ) The face of the luan has pockets that are actually shreading into wood strands. I have already resigned myself to filling and painting the tear next summer. I guess this is some more of that learning experience we are always talking about. :x

PostPosted: Mon Oct 27, 2008 1:00 pm
by Steve_Cox
This is a really interesting phenomenon now that there are many builders having issues with plywood de-lamination. The bubbles and waves in plywood have been happening for decades in work boats that have deck houses that are painted plywood. The thing is, you can use any material to build with, it is all about protecting it from moisture. By the time de-lamination becomes obvious, it's usually it is too late for plywood and replacement is the only real fix. Rot Doctor's CPES will restore solid wood and it will stop de-laminated plywood from rotting, but it won't put the laminations back together again, the only real fix is replacement. One thing about the plywoods of today; the glues are waterproof, but the wood isn't. Exterior grade plywood has a waterproofing on it, but when you cut it the end grain is exposed to the elements.

PostPosted: Mon Oct 27, 2008 5:44 pm
by planovet
Luan Bubbles, wasn't she a dancer once at...oh, never mind! :oops:

PostPosted: Mon Oct 27, 2008 11:46 pm
by reiltear
planovet wrote:Luan Bubbles, wasn't she a dancer once at...oh, never mind! :oops:


Great idea! Maybe Bubbles need(s) to meet some Dutchmen(plugs) or marquetry to make it look like it was meant to be there.

PostPosted: Tue Oct 28, 2008 5:26 am
by Spotman
planovet wrote:Luan Bubbles, wasn't she a dancer once at...oh, never mind! :oops:


Mark (and Cindi);

I can deal with those kind of bubbles, where is she? :twisted: Better than the ones on the camper... 8)

PostPosted: Tue Oct 28, 2008 6:29 am
by GPW
Same old story... Absolute sealing of EVERYTHING is the most important aspect of any TD finish...ask us how we know... :oops:

PostPosted: Wed Oct 29, 2008 8:56 am
by Miriam C.
How about an inexperienced voice. Cut the ripples. Apply lots of epoxy, even if you have to lay it on the side to do it. Then fiberglass it. No rebuilding needed.

You can also split the bulges and re-skin the whole thing. I have some luan I refused to use because sitting in my garage the top layer started to peal up. This time coat both sides of the wood. ;)

PostPosted: Wed Oct 29, 2008 3:13 pm
by Spotman
Thanks to all who responded. I have a small project ahead for me on this, if I run into anything needing your advice and helpful hints, I will be sure to post.

Again, this site has been so helpful in the past and now. Thanks so much.

Bob :applause:

PostPosted: Wed Oct 29, 2008 7:31 pm
by Miriam C.
Spotman wrote:Thanks to all who responded. I have a small project ahead for me on this, if I run into anything needing your advice and helpful hints, I will be sure to post.

Again, this site has been so helpful in the past and now. Thanks so much.

Bob :applause:


As you probably know others will have this issue and we really appreciate your post. We will also look forward to the "cure." I am sure it will be nice. :thumbsup: