warping

[northwood bob]

I don't know if you will remember but I gave a lengthy thread on the construction of this piece. By the way, My wife loved it.

A funny thing happened several months after it was hung outside. Looking out my front door, I could see a dramatic warp on the piece. The lower edge had warped about 2.5" outward. Mo cracks in the glue-up were present. The carving was on the sunny side of the garage and would see direct sunshine from sun-up till about 2:00 PM.

The piece is carved form western red cedar glue-up from 2 X 6 stock. The relief is about 1.0" at the maximum depth. My thought is that the grain structure had been comprimised at the deeper cutouts. A friend and I had a thought that possibly the front was drying at a differing rate than the back side. He suggested turning it around. Sure enough, after two days in the sun, the piece is back to flat. Now the question is "How do I keep it like that?"

Any thougts?

Bob

[mpounders]

I was thinking about cleats across the back. Do you think it is getting too wet and retaining moisture? It would seem the siding in the back and the way it is hung would prevent this, but you might try just attaching some temporary spacers to hold it further away from the wall and see if that helps.

[northwood bob]

My buddy and I are both engineers and had thought of cleats but couldn't comprehend what strength would be needed. We've all seen the results of wood warping, pulling out screws and tearing glue joints most especially on decks. If we try steel or aluminum angle irons, we thought we would just tear out the screws. If we tried wood cleats, I could glue and screw but couldn't be assured I wouldn't have tear-out. Add to this the probably size of the cleat would make the appearance on the wall unsightly. There is ventilation to the back by the vinyl clap-board siding but you're right, I think I am retaining moisture in the back.

What is your thought on coating the backside with marine sparr varnish? The piece is only coated with Thompsons Waterseal at this point (both sides liberally).

[Dougie]

Bob
I was told by a professional sign carver to use whatever finish you use both the front and the back to prevent warping.
I carved a sign for the house and it has been up 20 years without warping.
Doug

[northwood bob]

Doug
That's interesting.

What species of wood did you use? Which direction are the glue lines? What finish did you use?

I can assume but it appears that the relief is only the letters and I would assume you used 1" stock??? It could be because my relief is soo deep that the problem arrose???

Bob