What should I use to temporarily seal a bow

[osage outlaw]

I want to take my trade bow to the Classic so I can shoot it in and get some professional opinions about it.  I want to put a finish on it to protect it from moisture.  I hear it rains sometimes down there.  I have 3 choices; spray spar urethane, spray Deft wood sealer, or a can of shellac that I could brush on.  I will be removing the finish when I get back home.  Which one would be the best to use? 

[Pat B]

Shellac would be the easiest to remove later or any other finish can go right over the shellac. To remove it lightly sand it then wipe with denatured alcohol. A couple of wipes with alcohol should clean up the wood nicely.
  I'm bringing my trade bow also. Not quite finished yet though. I should have it shooting by then.

[IndianGuy]

If the bow is not going to have a backing just put a good coat of tung oil on it.

[osage outlaw]

Maybe you can test my bow for me Pat.  I am going to shoot it in over the next couple of days.

Indian Guy, I plan on backing it with rattlesnake skins.  Could I glue them down over the shellac?

Thanks for the help guys!

[Pat B]

You can glue the skins over the shellac. It will help prevent moisture from the glue getting into the dry wood.
  We'll compare trade bows. Mine will be naked and may need a little reduction still but I'm planning on shooting it some. It is an Eastern Woodland style locust bow and will have a hand rubbed bear grease finish when done.