Whenever a boat is hauled out to be scraped and painted it should be examined carefully for rot or worms and the various planks, the keel, stem, sternpost, centerboard, centerboard trunk and case and in fact, all the woodwork below water should be tested for teredos or rot by probing with the tip of a knife blade. If the wood is sound the blade will not penetrate readily, whereas if the wood has been injured by worms or is rotten the blade will enter very easily. When this occurs a thorough investigation should be made to determine the extent of the damage.
If the spot is small it may be dug out by a chisel or gouge and the cavity may be filled with white lead or marine glue and painted over, whereas if there is a large area damaged a new plank or a new piece of timber must be fitted. In any case every hole, crack or crevice should be carefully plugged with white lead or marine glue before painting, for if this is not done rot and worms will be almost certain to find the unprotected spots and will commence to destroy the wood.
If there is a stream or body of fresh water near at hand a great deal of time and trouble may be avoided by running your boat into fresh water and allowing her to remain there for a day or two at a time. Marine growths and teredos cannot live in fresh water and any which have become attached to the boat will die and drop off when the craft is left for a short time in fresh water. To be efficacious the water must be really fresh and not brackish, for many marine plants and animals will live and thrive in brackish water.
When boats are first placed in the water they are dry and often leak badly, but as the wood swells with the action of the water the seams tighten up and often a boat which leaks like a sieve when first launched will be perfectly tight after a few days’ immersion. For this reason you should not be discouraged if your boat leaks when you first put her in the water, but if she still leaks after two or three days you may be sure there is something wrong which should be attended to at once. By bailing out the water and wiping the inside dry with a sponge you can usually find the leak, and if it is small it may be stopped by pushing caulking cotton into the seam or crack with a thin knife blade or a putty knife. Very often a small leak may be caused by a nail hole and this may be stopped completely by driving in a tiny wooden plug.
If there is difficulty in locating the leak from inside the boat, if the leak is large or if there are several, the boat should be hauled out on shore and partly filled with water. Then, by watching the outside of the hull, you can easily find where the water runs out. The spots should then be marked, the water drawn out by means of the boat plug (a wooden plug driven into a hole through the planks near the keel), and the seams where the leaks occur should be cleaned free of all putty, paint and old caulking and should be recaulked.
It is an easy matter to caulk a seam if a little care is used, the only implements and tools required being a small caulking iron, some caulking cotton and a hammer. Unravel a strand of the cotton, roll it between your palms until it forms a strand a trifle larger than the width of the crack to be caulked and then press the end into the seam with a corner of the caulking iron or a knife blade. Catch the strand of cotton lightly into the seam in this way all along the seam and then with the caulking iron and hammer drive the cotton well into the opening. It is impossible to describe just how to use the iron, but it is a knack soon acquired and is accomplished by a sort of rocking motion with the iron as the tool is struck lightly with the hammer.
Drive the cotton well below the surface of the wood but don’t try to force in too much and don’t drive it in so hard that it spreads or starts the plank. When the seams are well filled with cotton press white lead or marine glue over the caulking and paint thoroughly. Never use putty on a boat, especially below the water line, for it will crumble and fall out very soon and is no better than nothing at all. Use pure, thick white lead and linseed oil or the best marine glue. The white lead may be pressed in with a putty knife but marine glue must be run in by means of a hot iron; full directions accompany the glue when purchased.
Caulking Tools
1—Caulking mallet. 2, 3, 4, 5—Caulking irons. 6—Caulking hammer.