Black walnut body and stinger.
It can be bright, but it also gets a great LP tone.
http://www.youtube.com/watch?v=0CR1IhHI--U&list=UU9seQgCX5cpOBsheVeJJyXQ&index=9&feature=plcp
http://www.youtube.com/watch?v=qTBqH7HxJOE
It's an Epi I picked up dirt cheap( $200 shipped) with a seperated neck joint. Brand spanking new. There was almost no glue in the neck joint, glued it up, pulled the plastic off of the pick guard and pups and it plays and sounds great.
It would be best to let sleeping dogs lie, change the rubber out on the hanger and not mess with the finish, but he seem intent on trying to clean it off. Bad move IMO, but hey it's not my guitar. If I were him I would test whatever he's going to use on it, under the pickguard, or in the pickup...
You already know the reason why, and it has nothing to do with the reason the OP's guitar is having a reaction with hanger he's using. That's the reason I asked you why you brought it up.
You can have all the plastic coated guitars you want:thumb:
As for me, I'll finish mine in nitrocellulose lacquer, and I like checking as long as it's natural.