Popular Science, heinäkuu 1944
Timely work with the brush will prove that real key to keeping any craft, small or large, always in good trim
By Elon Jessup
Men experienced in salt-water boat yards will tell you that if you put off the repainting of a bottom for as long as two years your boat is a goner. With new pleasure boats now practically off the market, this means that your old craft, if it is to last and give good service, is going to need a repaint and varnish job without delay.
But professional painters are hard to get nowadays, and the boat yards are all busy with Navy work. It looks as if you will have to do the job yourself.
Good paint, fortunately, is still procurable. Some are of the opinion that sooner or later it won't be. It contains ingredients - especially copper bottom paint - needed for the war. The wiser boat owners aren't taking a chance. They say, get the paint and put your boat in first-class condition while you can.
Your craft may be anything from a 7' dinghy to a 60' cruiser. The method of painting it won't vary basically. But in every case you must investigate and formulate a definite plan. Otherwise you may either skimp on essentials or let yourself in for a lot of hard work that isn't necessary. A boat-painting job can be made easy and still be thorough, or it can be difficult and complicated. Take it easy. And take your time. The job simply can't be rushed.
A good example of planning is in deciding the question of whether or not an old paint surface ought to be completely stripped off- down to the base wood. In some cases this will be essential, while in others it won't. Again, on a given craft, stripping may be required for the top topsides and not for the deck - or the opposite may be the case. You must investigate and judge for yourself. It would be foolish to distrub old paint that is solidly bonded to the wood and neither cracked nor blistered. A solid, firm base of this sort is an excellent one upon which to spread a new coat of paint.
Complete stripping down is required when the old paint has gone lifeless and no longer provides a firm base to which new paint can cling. But it is usually a matter of years before this stage is reached. To strip down a boat every year, as some boatmen do, is rarely necessary. You will recognize the real need by the cracking, blistering, and flaking of the old paint. And you can be sure things are in bad shape when the paint peels off in strips. The best way to find out how matters really stand is to go over the entire surface with sandpaper.
There is a convenient short cut for dealing with flaked and blistered paint. This is a method known an spot painting. After a thorough sanding of the surface to bring off all the old paint that can be loosened, leave the paint that remains firm undisturbed and then paint only the spots where bare wood shows. The boat will look like a leopard at first, but after the spots have dried, a finishing coat is spread over the whole surface, and then your craft ought to look as good as new.
A more thorough and lasting method of treating flaked and blistered paint is to strip down the entire old paint surface. A blowtorch is the favorite tool for the job, and it provides the easiest way. The torch is held in the left hand while, with a putty knife in the right, you peel off streaks of hot, softened paint.
Be sure never to use blowtorch on canvas - either canvas decks or sides. It is likely to scorch and ruin the cloth Paint remover should be your medium for stripping this material. The use of paint remover is also more suitable than a blowtorch for vanished surfaces. Black scorchings from the torch will always show unpleasantly through a new coat of varnish.
Another tool that does a good job of stripping both paint and varnish is a power sander. Its use, however, is sometimes more practicable for decks than sides, for a power sander is a heavy implement to hold against a sloping topside.
It is difficult to plan the real painting requirements of a boat without first giving the craft a sound scrubbing with soap and water, inside and out, from stem to stern. This may disclose certain structural weaknesses as well, such as loose fastenings or sports of dry rot in the wood. Now is the time to repair these places, before any new paint goes on. There is one exception to this. You will propably find seams and nail or screw holes that need to be puttied. Postpone this particular chore until after a priming coat has been applied over the wood. When this has been done, the putty will cling all the better.
Both the weather and the amount of protection your boat enjoys will have a bearing upon how you plan the actual painting. If the boat is berthed in the open and has a cabin, it may prove good planning in uncertain weather, such as that occuring in the early spring, to tackle the interior first. But generally speaking, it is a waste of time to paint or varnish during damp or cold weather. Even if you have your boat under a shed, wait for a spell of settled, fair weather. Then do the painting from about 10 o'clock in the morning until three in the afternoon to obtain the best results.
It will make your work easier in the end if you give the boat a second thorough scrubbing with soap and water a short time before laying on paint. After this, regardless of whether a complete stripping down has been done, it is essential to sandpaper all parts that are to be painted. If this sandpapering brings off any blister patches, spotpaint them and let the paint dry. The surface should always be thoroughly dry and free from dust before any paint is applied. If paint remover has been used, the wood should be washed down with turpentine to get rid of the wax in the remover.
Generally, the easiest system in painting is to start at the top and work down - as you'd do in painting a house. However, some boatmen find it more convenient to paint the topsides before the deck, that is, the sides between the water line and rail. The bottom comes last. Use only a reliable marine paint - not a house paint. No matter how good, house paint won't stand up in the water the way marine paint does.
Here is the easiest and best wat to paint the topsides. commence with the brush at the starboard bow and work aft, gradually going around the boat in a clockwise direction and ending up where you started under the bows. This is, of course, on the supposition that you are right-handed. In following this method, you profit by having a finishing stroke that is continually forward instead of backward. A person accustomed to holding the brush in his left hand will get the same results by starting at the port bow and working around the boat counterclockwise.
Two coats should be enough on an old, firm paint base. Thin down the paint with turpentine for the first coat, perhaps by about 10 percent. The second coat will usually be laid on as it comes from the can. Paints vary, however, and the best system is to follow closely the directions a manufacturer prints on the container.
After the first coat has been applied, putty seams, nicks, and hole where this is needed. Although in some instances recalking may be required, as a rule it is best to leave the old calking undisturbed. As for putty, ordinary window-pane putty won't do. The variety most used for general plugging is white-lead putty. For seams - including those on the deck - a putty of prepared elastic seam cement is preferred.
Painting of decks and the interior follows much the same procedure as that of the topsides. Here, too, be sure the first coat is thoroughly dry before laying on the second. If the weather isn't just right, the surface may remain sticky for days or even weeks. Don't rush it. Before applying the second coat, sandpaper the first lightly.
Between the topsides and bottom on some boats, but not all, is a wide, decorative stripe running from stem to sern. It is known as the boot-topping and serves as a sort of water-line barrier against grease and dirt in the water. Paint it with a very hard enamel that will take plenty of scrubbing.
Then, finally, you get to the bottom and something radically different in paints. There are many kinds of bottom paints. Your selection should be determined first of all by whether your boat is kept in fresh water or salt water. The safest rule to follow is to choose the brand commonly used by boatmen in your own locality.
The marine pests of salt water require special ingredients in a paint. Marine worms won't go through paint, but they will quickly penetrate any bare wood where paint has come off. Watch the boat's bottom. It is the part of a craft requiring the utmost attention and, unless properly protected, it is sure to give trouble. The bottom of every salt-water boat must be painted once a year at the very least, and usually it should be painted even more frequently.
Most pleasure craft that cruise salt water require a soft copper antifouling bottom paint. Before applying it, sandpaper the bottom to free it of all loose paint and dirt. Boat yards sometimes speed this job up by playing a hose on the bottom and scrubing with a harsh broom. The surface must be left to dry, after which the first coat is applied. Between coats, as in the case of topsides, putty up all holes.
Let the first coat dry thoroughly before applying the second. But this second coat is treated differently. Postpone putting it on until about an hour before the boat is scheduled to go overboard. The bottom ought to go into the water still a little wet. When it does, there will be a slow release of poison from the paint to discourage parasites from taking hold.
The fresh-water boat owner hasn't as much to worry about. A hard-surface paint and an occasional scrubbing ought to keep the bottom of his craft clean.
While any boat is afloat, give her a periodical washing with fresh water. This keeps salt and dirt from baking into the paint.