I am in the process of painting my boat trailer.  I have already sanded and put 2 coats of primer on it.  It wasn't fun laying under the trailer painting the places under the boat.  I have put one coat on the side of the trailer.  My question is I was thinking about putting the boat in the water, then I can bait the trailer pretty quickly with the boat off and I can get to the corners better.  I was then thinking about then taking the boat out as I let the paint dry.  I am using a oil based paint, and I was wondering how long I should let it dry until I am safely ok to back it into the water to load the boat back on it.  My dad was saying I should let a oil based paint sit over night before dunking it back in the water.  I was thinking that if I paint it early in the morning 8-10am, then let it sit in the sun and dry that I should be ok to load it about 5-6pm.  

How much time should I let it dry before loading the boat back on it?

Depends on what you are mixing the paint with. Thinners, retarders, etc. will determine the drying time for the final coats. Several hours should be fine for backing it in the water, just understand that the paint will not have hardened and can be damaged easily. Especially if you are applying thicker coats.

I haven't been adding any thinners or anything to it.  It's a old boat trailer, and not like the new bass boat trailers that look like showroom shine.  It had some rush and needed and freshen up.

Several hours should be fine to back it in and load a boat.

I agree with a giving it atleast a day to dry in the sun, 6-8 hours should be plenty.

Bill

You will be fine with 6-8 hours. Oil paint dries as your reducers evaporate so as long as it has tacked up(fairly dry to touch) the water should not effect it It will only stop it from curing while it is in the water. Once removed from the water it will begin to cure again.

Thanks everyone.  Yeah Painter Dude, that was what I was thinking but just wanted to make sure.