Floatation test question

[makemyown]

Ok so I have just finished planking the hull on my boat, I have never built a boat from scratch before so I have a question... Can I throw my boat in the swimming pool to check for leaks and if it will stay afloat before finishing or caulking. The plank is pine and cedar. In all the boat buildalong books that I have they always caulk and paint before ever putting it in the water. I am anxious to see how good my joinery is and I can't wait, I want to see if it leaks and where, before caulking and finishing it. Is this okay? or bad idea?

[Bob Smalser]

Whad'ja build?

If the design requires caulking and you haven't yet, it'll promptly sink up to its gunwales, and without installed floatation it may be a real chore to get it out of the pool without damage.

[BBSebens]

If by pool you mean swimming pool, then I have to wonder what all those chemicals will do to the paint that will go on later.

Best bet is to be patient. You got this far, better do it right.

[wizbang 13]

If it needs caulking it will leak. Joinerwork does not make a boat tight, caulking (or glue) does.
If it needs painting it will get wet. Chlorine undercoater?

[woodpile]

The swimming pool can come in handy but I used it in a different way. Used 2" thick closed cell foam under the sole in the J. B. lobster skiff. Cut a piece of the foam one foot square, put it in the pool with a bucket on top of it and started adding fishing sinkers in the bucket until the foam submerged, was pretty amazed that it took about 8+ lbs. The total square footage amounted to 280 lbs. of flotation. I don't know exactly what that means in terms of the Coast Guard flotation requirements but I do feel comfortable knowing the flotation is > the weight of the motor, fuel, battery and total of the non-wood parts of the boat. Based on seeing the foam installation in many tin boats I think I'm in good shape.

[makemyown]

Whad'ja build?

If the design requires caulking and you haven't yet, it'll promptly sink up to its gunwales, and without installed floatation it may be a real chore to get it out of the pool without damage.

I am sorry I forgot to mention it is Batten Seam construction. In my mind the batten should keep out the water on the sides well without calking but I am more worried about where they meet the stem I want to check to see if my joinery is good there. Just because I put the work in I am curious now to see if it is good or not without caulking.

This is the boat: http://www.vintageprojects.com/boats/biloxi-dinghy.pdf the plan seems to call for rabbet joints on the side and batten/seam on the bottom but I did the sides batten seam aswell because I like it more.

Thanks Bob

[MN Dave]

No worries. They launch the boats at various family boat building events as soon as they are built, but not finished, and the water they launch in is nowhere near as clean as a swimming pool. The swimming pool chemicals are too dilute to do any harm. It is not unusual for a boat to leak a bit until the wood swells and tightens up the seams.