Bluedog,
There are a few things to consider regarding what kind of finish you want.
First its almost a crime to put anything on teak. If you were making furniture you could scrape the wood and then burnish it brining out the natural oil in the teak. This is by far the most natural way and the best look in my opinion. There are some light danish oils that can be used to keep furniture pieces from 'drying out'. Problem is, that "natural" provides very little extra protection to the wood in the ocean. Many like teak oil (virtually all products sold as teak oil are a mixture of tung oil and other distillates) or pure tung oil. Many of the teak oils I tried "stained" my guns dark brown which I didn't particullary care for. Use a left over piece of teak to spot check what ever product product you end up using. Pure tung oil by itself provides minimal protection but maintains some "natural" look. I have knocked my reef guns into the reef and left deep gouges in the wood right through the tung oil and other light finishes. For this reason, I have turned to epoxy for my reef guns because it creates a very hard and thick surface. Three coats of epoxy probably equals about ten coats of varnish or polyurethane and the dry time and shrinkage is greatly reduced with epoxy. Problem with epoxy is that it "chips" Again, my thinking is that it is better to chip the expoxy then to gouge the wood. Usually at the end of the "season", i simply sand the chips and scratches and add another protective coat of epoxy.
The other problem with epoxy is it can have trouble adhering to the teak if the teak surface is not properly prepared. You definitely want to use west system epoxy becuase it has held up to the test of time. There is no need to 'raise the grain' with teak in general, and you surely don't want to do it with water. If you are intending to use a waterbased stain or water based polyacrylic and are worried about the grain popping, you might try some distilled water, but again, the natural oil in the teak would just make the water bead up and prevent expoy or oilbased finishes from properly adhering, especially if the wood was not completely dried.
Try this method ....scrape the teak...if you don't have a scraper, sand the teak but don't sand past ~180 grit...Remember, you want to have the expoy penetrate and adhere to the wood sanding too fine will prevent this...plus under three coats of epoxy no one will be seeing the sanding scratches anyway. Rub/clean the wood with acetone to remove all the natural oil...this will take some effort. Also, don't sand the wood after cleaning with acetone or you'll just bring more natural oil to the surface. For the first coat, Dilute the West System epoxy with upto 15% acetone (don't worry about strength because this is not structural). You want the first coat to soak in. You can also warm stock by leaving it somehwere hot. After the first coat has time to soak in, rub off any excess epoxy with a clean rag and let it cure. Lightly sand, and apply 3 coats of epoxy at full strength,scrapping (if you want a perfectly flat finish) and sanding between coats. Dont' build the coats too fast or the epoxy will "run". It will take some practice to see how thick you can make the coats. You can follow the last coat of epoxy with tung oil or varnish (u/v protection). Or, you can lightly sand and rub out the final epoxy finish to a satin, semi, or high gloss and put some carnuba wax with U/V inhibitor (automotive store) on it to bring out the shine.
I posted a similar thread under "speargun pictures" pg. 5?
Good luck
