310 
FOREST AND STREAM 
March 9, 1912 
and put aside to dry thoroughly before varnish- 
ing. 
Any painted or varnished work that has, 
through age or exposure, become blistered or of 
bad appearance, should be cleaned off down to 
the bare wood by scraping or the use of a chem¬ 
ical solvent, or, in the case of paint, by burning 
off. But such work is not to be lightly under¬ 
taken by the amateur, and wants considerable 
time and care expended to make the result 
satisfactory. Not only does the cleaning off take 
some time, but the subsequent recoating is a 
much longer job than the ordinary “touch-up 
and one-coat” so that cleaning off should not be 
started when time is limited. 
There are several chemical solvents on the 
market, and one may use more or less ordinary 
materials, such as caustic soda, as paint or var¬ 
nish removers. However, it is better to stick to 
something specially put up for the purpose, as 
the very strong alkalies are unpleasant to use, 
and apt to damage the wood. Some of the best 
varnish solvents are made with a spirit base and 
■vork very well indeed where there is not too 
great a thickness to remove. None of them are 
so successful on very old work, usually leaving 
a patchy effect. They are, too, rather expensive 
to use in such cases, for several coats must be 
applied in order that the solvent may get right 
through the many layers of varnish. We have 
tried several of the solvents on the insides of 
old boats, and must confess that the results have 
been, in every instance, decidedly disappointing, 
not only as regards the expense, but the appear¬ 
ance when finished. Whatever solvent be used, 
the greatest care must be taken to insure that it 
is really killed by washing with the material 
recommended by the makers. We have found 
raw carbolic acid to act very well as a varnish 
solvent on mahogany, and it leaves the wood a 
good color. It must be thoroughly washed out 
with plenty of water and to finish with turps. 
As the washing off wets the wood and causes 
the grain to swell up, the work wants a thor¬ 
ough rubbing down with sandpaper, or even 
hand scraping or planing, after the use of any 
solvent, especially on the softer woods. It is, 
therefore, questionable if it really pays to use 
any solvent at all, provided, of course, that the 
workman be capable of scraping off by hand 
without ruining the work by scratches and goug¬ 
ings. Generally speaking, we consider their use 
to be justified on teak work that has but six or 
eight coats to be removed, and that it does not 
pay to use them on mahogany at all, except on 
intricate work where hand scraping would be 
very difficult. 
Hand scraping is, at tlie best, a tedious pro¬ 
cess, and one that is apt to become very boring- 
after a few hours’ close application. There are 
two essentials—good scrapers and plenty of 
patience, and without these the task of scraping 
a boat is a hopeless one. The roughing scrapers 
generally used are made of old files and are 
formed by forging down the end of the file to 
a thin edge and turning it over into a hook, the 
edge being filed or ground sharp and slightly 
rounding to prevent the corners digging in. 
These are home made, but triangular scrapers 
may be purchased ready for use. For finishing- 
flat surfaces after rough scraping, a “dumb” 
scraper must be used, this being a thin, rectangu¬ 
lar saw steel blade about five by three inches 
with the edges ground up square and worked 
up for use by stroking with some smooth hard 
steel tool, such as the back of a gouge. The 
stroking raises a slight burr which causes the 
scraper to cut properly, but it is practically im¬ 
possible to describe how such a scraper should 
be sharpened. One must be shown by an expert, 
and a good deal of practice is required to ac¬ 
quire the knack of getting and keeping scrapers 
in good condition. For working out mouldings, 
headings, etc., scrapers of special section must 
be made, and a lot of the work done by sand¬ 
paper. It often pays to remove mouldings, or 
take down work that is screwed up, and use the 
plane after rough scrapin.g. It is most difficult 
to make moulding look well if done right through 
in place. 
Painted work is best cleaned off by burning, 
just as a house painter does a door. A paraffin 
or petrol burning blow-lamp is used to heat the 
paint until it becomes soft, when a blunt, square- 
ended “stripping knife” is pushed along and 
peels off a long strip of paint. A little practice 
will insure a clean strip off without any scorch¬ 
ing of the wood, and in this connection it should 
be noted that a blow-lamp burner with a spread¬ 
ing, instead of a concentrated flame, gives the 
best results. After burning off, all cracked or 
loose putty and stopping must be raked out of 
the seams with a hook, and the wood must be 
thoroughly surfaced down with sandpaper before 
priming. Any bad bruises should have pieces 
of wood neatly let in, and glued and bradded in 
place, and of course any defective or rotten wood 
must be replaced by new as required. If one 
goes to the trouble of burning off, one might as 
well make a good job of repairs at the same 
time, and it may pay to fit, for instance, new 
rubbing pieces of gunwhale cappings, if the old 
ones be much knocked about. 
Fouling and its Prevention. 
Of these anti-fouling compositions, as they 
are termed, one can only speak in general, 
owing to the extreme variability with which 
they carry out their duties. It is easier to de¬ 
cide on a composition intended for a ship which 
travels to and fro through the same, or prac¬ 
tically the same, waters—and such a decision 
can only be arrived at by successive and exhaus¬ 
tive trials—than in the case of a ship visiting 
port after port around the world. However, 
even where a ship traverses the same waters, 
under the same conditions and treated with the 
same compositions, she will sometimes return 
foul and sometimes clean, and the causes are 
next to impossible to explain. Of course, the 
season of the year and the corresponding con¬ 
ditions of the water affects the action of the 
composition. 
Right from the earliest times, fouling has 
been a source of much worry and experiment. 
In the days of the wooden sailing ships, sheath¬ 
ing with copper plates was carried out, and we 
find it used in many cases to-day. On some of 
our own and foreign warships, intended to be 
away from dock for long periods, the steel 
skin plating is covered with a wood sheathing, 
outside which copper sheets are fastened. 
Copper cannot be attached directly to steel, 
otherwise galvanic action would be set up and 
the steel would be eaten away. The wood 
sheathing is therefore fitted to insulate the one 
from the other, and extreme care is obviously 
necessary to prevent metallic connection be¬ 
tween the steel and copper. 
Copper very easily corrodes in sea water, 
owing to the action of certain salts, and this 
results in the appearance of the well-known 
loose coating of “verdigris.” This green coat¬ 
ing is very easily removed—in fact, is washed 
away by the water itself. The barnacles and 
seaweed which become attached to the copper 
thus lose their hold, and we have, as a result, 
a perpetually clean ship. This method is, how¬ 
ever, very wasteful, the copper wearing away 
far too readily, and hence being very expensive. 
For this reason, patent compositions have been 
brought out by the score, aiming at - greater 
economy. Most consist chiefly of copper, which 
is made to wear away at a slower rate. The 
peeling off is termed “exfoliation.” Here again 
one sees now a composition must be made up 
to correspond to the usual speed of the ship, 
so as not to exfoliate too quickly or too slowly. 
If exfoliation is too slow, of course the growths 
become attached and will impede the ship. The 
“verdigris” consists of salts insoluble in water 
formed by the oxidation of the copper by the 
sea water. One strange thing is worth noticing, 
viz., the more impure the copper used for 
sheathing the more difficult it is to ren-iove the 
insoluble coat. Poor copper will therefore offer 
few if any advantages as an anti-fouler, since 
the growths will not get washed away. If 
abrasions of the copper sheathing takes place 
and water gets behind the wood, rusting of the 
iron ensues, and the action is hidden from view 
until noticed from inside the ship, or until the 
sheathing is removed. 
The perfect anti-fouler is probably as unat¬ 
tainable as the elixir of life, for the different 
conditions under which a ship sails necessitate 
different qualities in the composition. Some of 
the compositions work on the poisoning and 
some on the exfoliating principles; but the ma¬ 
jority comoine both, and it is in the compro¬ 
mise that the different qualities of the composi¬ 
tion appear. Certain growths require more of 
the poisoning elements; others more of the ex¬ 
foliating; and so on. The great thing to re¬ 
member with all growths—seaweed or shellfish 
•—is that they do not get their nourishment 
through their roots, i. e., through the portions 
of their structure adhering to the ship. The 
vegetable growths in water receive nourishment 
through the pores in their "leaves” and the 
animal growths through their heads—i. e., the 
portions farthest from the ship’s plating. From 
this it is easy to see that poisons are of little 
use unless they attack the growths early in life. 
The poison leaks from the composition by ex¬ 
foliation. Hence, if a growth commences while 
a ship is lying alongside a quay or jetty after 
coming out of dock, where she has been cleaned 
and re-painted, the poison has little or no 
chance of doing its duty, as motion of the ship 
is necessary to carry out the exfoliation fully, 
and so release the poison. Afterward it has 
little chance of reaching the vital organs of the 
growths. This applies to both animal and vege¬ 
table marine life. However, once either is re¬ 
moved it cannot re-attach itself any more than 
a flower once plucked can re-instate itself on 
the stem of an ordinary plant. 
The poisons used are usually metallic, includ¬ 
ing arsenic, mercury and copper, and hence 
these are liable to set up galvanic action with 
the iron, and it is quite possible for the harm 
done in this way to eclipse the good effect of 
the poison. There are also rather complicated 
chemical reasons which further illustrate the 
weakness of anti-fouling compositions relying 
on poisoning principles only. Each particle of 
poison is surrounded by the oil or varnish used 
in the manufacture of the composition, and 
hence in a manner is itself “protected” from the 
sea water. As we have seen in a previous 
article, a good varnish only disintegrates after 
some months of immersion, and it is only after 
this takes place that the water can reach the 
poisons and become contaminated by them. 
The germs of growths attach themselves, in the 
first instance, while the ship is lying moored 
in the usually dirty stream and are therefore 
unharmed by the poisons, and we have seen 
that once a growth has reached any size it is 
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For charter, ship fully equipped, specially built 
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Greenland or Spitzbergen and Franz Josef’s Land 
waters, will accommodate party of 5 to 15. Polar 
bear, reindeer, fox, seal, walrus, Arctic birds, 
fishing. 
ARCTIC, 1004 Oliver Bldg., Bosfon, Mass. 
ARTHUR BINNEY 
(Formerly Stewart & Binnev) 
Naval Architect and Yacht Broker 
Mason Building, Kilby S(., BOSTON, MASS. 
Cable Address, "Designer,” Boston 
COX (Si. STEVENS 
Yacht Brokers and Naval Architects 
15 William Street - New York 
Telephones 1375 and 1376 Broad 
YACHT and BOAT SAILING 
"By ihe lata Bijeon K.emp 
Tenth edition. Published 1904. We have a copy in 
fairly good condition, published at 912, which we will 
sell for 99 . 00 . 
FOREST AND STREAM PUBLISHING CO. 
