RE: Warped ARF Stab- How to fix it?
I had the same problem once before. I removed the covering in the recommended area that was to be glued into the rear of the fuse. I then used a wet rag and applied a liberal amount of water to the balsa and then laid a heavy book on it over night and that removed the warp. I am not saying it will help your problem, but it did mine. Or you could do what ChuckW said and contact Sig.