390 
FOREST AND STREAM. 
[May 17, 1902. 
Designing Competition for the Sea- 
wanhaka^, Corinthian Y. C. 
To be Known as the Seawanhaka 15-Footefs. 
The competition is open both to amateur and profes- 
sional designers. Three prizes will be awarded^ for the 
best designs of a yacht conforming to the following con- 
ditions : 
I. A keel sloop to measure 15ft. racing length under 
the club's new rule. 
II. Sails: Mainsail, jib and spinnaker. The area 
of the mainsail and jib shall not exceed 350 sq. ft., not 
over 80 per cent, of which shall be in the mainsail. 
m. Planking shall not be less than 5^in. in thickness 
IV. Spars shall be solid, and the mast shall be of 
sufficient strength to be used without runners or pre- 
venter backstays. 
V. Cockpit shall be open, and bulkheads or air tanks 
are to be provided sufficient to insure the boats being 
non-sinkable. 
VI. The boats shall be capable of carrying full sail in 
ordinary summer breezes on Long Island Sound. 
VII. Construction shall be strong and durable. 
VIII. All competitors must furnish a drawing of the 
lines, which will also show the position of the lead keel, 
and a table of calculated weights, which will give dis- 
placement, weight of lead, weight of hull, weight of rig, 
center of buoyancy and center of lateral resistance, center 
of effort and center of gravity of the lead keel; also a 
sail plan, on which the diameters of spars and sizes of 
rigging shall be marked ; also a deck plan and amidship 
section, which will show height of cockpit seats and floor, 
and height of coaming. The midship section must also 
show the construction. 
The boats are to be measured with a crew of two men 
aboard, their weight to be taken at 30olbs. 
The actual sail area will be measured. 
The following prizes will be awarded: First prize, 
$100 ; second prize, $50 : third prize, $25. 
In the event of one of the prize designs being selected 
by the club and yachts being constructed therefrom, the 
winner, in lieu of the cash prize, may furnish the neces- 
sary additional plans and specifications and supervise the 
construction and receive $25 for each yacht built. In 
awarding the prizes, speed will be the first consideration, 
but appearance, construction, simplicity of rig and con- 
venient arrangement will also carry weight. 
Sail plan, Y'm. scale. All other plans, iin. scale. 
The designs must be received at the office of Forest Avn 
Stream, 346 Broadway. New York city, not later than 
May 15. 1902. and should bear a nom-de-plume only. A 
sealed envelope containing the designer's nom-de-plume. 
together with his mvn name and address should accom- 
pany the designs. The right is reserved to publish anv or 
all of the designs. Those desiring the return of their 
drawings should inclose the necessary postage. 
The designs will be judged by a committee consisting 
of Messrs. John Hyslop. A. Cary Smith. J. Rogers Max- 
well. Jr.. and Clinton H. Crane, and the result of the 
competition will be announced through these columns in 
the issue of May 24. 
The club's new rule referred to in Paragraph T h as 
follows: Yachts shall he rated for classification and time 
allowance h v raring measurement, which shall he de- 
termined bv addinsr to half the load waterline leneth 
half the ^nuare root of sail area, and a nuantitv expressed 
as L, and by dividing the sum of these quantities by 1 i 
% LWL + )i VSA + L _ _ 
i7i RL 
The quantity L is to be obtained in the following way: 
,s b readth , of lof >d waterline plane at Y s of its length 
from forward end. 
B' is breadth of load waterline plane at % of its length 
from after end. 
B" is breadth (greatest) of LW plane. 
C is any excess of (B+B') over B" 
D is draft at MS+2-5 of any greater draft aft, and all of 
any greater draft forward. 
C+S eXCeSS ° f (B " +D) over 3 1-3 VMS submerged. 
Manhasset Bay Y* C 
PORT WASHINGTON, LONG ISLAND 
The Manhasset Bay Y. C. held the first race of the 
season off their club house, Manhasset Bav. on Satu - 
day May 10. Four of the club raceabouts started. The 
boats rigs have been changed since last year, the bow- 
sprits having been lengthened, and they have received new 
cross-cut sails. Mr. Edward MacLeflan, of the ReeaS 
awT^r/oh" 6 ^ at ^ Mist wa?fiS 
way closely followed by Arizona; 15s. later Bab and 
Lambkin crossed. The wind was fresh from the nor"h 
mark inC Bah ed T the boats -ached tL first 
mark. Bab worked into first place before reaching the 
SfabSTf 5 n . d he ! d thel , ead l / t0 the iWS 
lows. m ength - The times were as fo1 " 
Start, 3:40. ■. v ■ u -cm 
Bab, John R. Havt f^' 15 ^ S ifi" 
Lambkin, S. W. Roach | - J « lo 
Mist, J. W. Alker 5 |f £ J S .M 
Arizona, G. A. Corry [ [ \ [ [ [ [ [ \ \ \ % % | \ | | 
Jamaica Bay Y. R* A. 
The Jamaica Bay Y. R. A. "has been organized with the 
following clubs as charter members: Canarsie Y C of 
Canarsie; Jamaica Bay Y. C, of Hollands Station, Rock- 
^i' J ay A r B ^ a . C J i; ^ Bergen Beach Y - C > of Bergen Beach, and 
Old Mill Y. C, of Brooklyn. 
At the meeting held a few days ago the following offi- 
cers were elected : Chairman, B. F. Daly, Jamaica Bay 
Y, C; Vice-Chairman. H. C. Macy, Canarsie Y. C. ; 
J teas., Henry Lang, Old Mill Y. C. ; Sec'y E V Par- 
dessus, Bergen Beach Y. C. 
The racing rules of the Association will be drawn up 
by a committee composed of H. C. Macy, Canarsie Y C - 
Com. Frank Sabin, Jamaica Bay Y. C, and Com. Henry 
Lang, Old Mill Y. C. 
The first race will be held some time during the month 
of June, and will be sailed oyer the Jamaica Bav Y C 
Course, ' • '- * ' ■' 
How to Build a Launch from a 
Set of Plans. 
BY C. G. DAVIS. 
T he Plans. 
Different designers have different ways of drawing out 
their plans of boats, just as every man's handwriting is 
different, yet all have the same meaning. In Plate 2 I 
have represented four different ways in which the plans 
shown in Plate 1 may be represented. No 1 is the most 
common way of drawing out the lines of a boat ; No. 2 is 
the same, but space has been economized and time of 
remeasuring saved by putting the sections over the middle 
of the sheer plan. No. 3 is the same as No. 2, excepting 
the moulds have diagonal lines drawn in. No. 4 shows 
each section projected on its own line somewhat after 
the style in Plate 1, only each section has had to be re- 
measured in order to get its depth. 
Plate 1 is just such a design as I would draw were I 
designing the boat. Every line necessary for me to draw 
in order to be assured the moulds are fair and_ ready to 
build from is here represented. Now to explain to the 
novice the meaning of these crooked lines let us digress a 
moment. 
In draughting there are three views of any sbject you 
wish to represent, usually drawn. For instance, to illus- 
trate a box gin. long, 6in. wide and 3m. deep, you draw 
the top view, side view and end view, Fig. 8. But these 
V/FU/ OF 80X 
Plan of box. 
Fi<5-8 
are not called lop, side and end; they are termed plan 
view, side view or elevated and section view. With any 
two of these it is possible to produce the third. If you 
have the plan view and side view, and want to draw the 
section view, it is very simple, so long as you are only 
considering a rectangular box; the width, 6in., gives you 
the top and bottom lines of the end section, and the depth 
of the side elevation, 3m., gives the depth of the sides at 
the end. But if this were a tapered box, or better yet, a 
cone, Fig. 9, you can readily see that every section 
V/FIV OF COA/f 
PLf{N OF CONS' 
throughout its length would not be the same size as the 
end ; this is all there is to the sections of a boat as 
drawn in our plans j they merely show how much the 
launch tapers, both in width and depth, as the sections 
approach the ends. 
The sheer view gives us the shape of the launch were 
she cut right in two down the center line; the rabbet 
line shows where the planking ends and the three but- 
tock lines show how the boat would look were she sliced 
down in layers at the various distances out from the 
center as shown in the plan view. No. 1 being 6in. out, 
No. 2 being 12m. out and No. 3 — i8in. out from the center. 
In the plan view the various waterlines represent the 
shape were the launch cut. in layers horizontally, and the 
sections are the shape of the launch were she cut into 
pieces at the various places along her length, indicated 
by the sections marked A, B, C, D, E. 
It is to make sure that these sections "fair up," as it is 
technically called, that all these buttock and waterlines 
are drawn. They do not concern the builder much, but 
the designer by laying off the widths of the waterlines or 
heights of the buttock lines from the moulds or sections 
he mas drawn, can prove that they are fair by bending a 
small batten from spot to spot from one end of the launch 
to the other. If the batten bends in a fair curve through 
all the spots as represented in our plans, the plan is said 
to be faired up. This means that if the full-sized moulds 
are made according to these sections, the ribbands and 
planking will bend around true and fair. 
The diagonal lines shown in No. 3, Plate 2, are used 
by many designers as fairing up lines because they cross 
the section lines more nearly at right angles and so give a 
more positive point to measure to than do the buttock 
and waterlines that cross the sections in some places at 
very acute angles. 
Most designers measure off the various heights of sheer 
line, buttock lines and keel line above the base and the 
half-widths of deck line, waterlines, diagonals, etc., at each 
section, and write them in tabulated form, which is called 
the table of offsets. In Plate 1 I have done away with 
any need of a table of offsets by writing the measure- 
ment of each spot directly on the plans. It makes a more 
compact form which experience has proved to me to be 
sufficient. 
Laying' Down— Full Size. 
Draughting on paper with a small scale, where every 
inch represents a foot, is something you can hardly expect 
of the practical boat builder who spends most of his 
working hours pushing a plane, sawing, hewing and do- 
ing all the manual work required in the trade. 
But every workman can handle a 2ft. rule, try-square 
and carpenter's pencil or scratch awl. 
To prepare to enlarge the plans to full size you need a 
chalk line to snap such lines as the base line, waterlines 
and buttocks with ; a small brad-awl to hold one end of 
your line to the floor; a wooden straight-edge about 6ft. 
long, 4m. wide of %in. pine, which you can plane up 
true on one edge; a steel try-square, 2ft. rule, pair of 
carpenter's dividers to prick off the thickness of the plank 
after you have drawn in the sections, sweep circles and 
all uses where you want to transfer a measurement. A 
hammer and handful of wire nails about 2in. long to 
hold your battens in place on the floor. Another handful 
of flat head 3<*in. wire nails to lay along the marks and 
transfer the lines on to the pattern boards. A pine batten 
as straight and true as can be got about iin. square and 
20ft. long, and several small ones, some about jHsin. square 
throughout their length, some tapering from %in. square 
to % by }i'm. for bending the short curves, such as 
sections and fore ends of buttocks. 
If you have a good smooth board floor where pencil 
marks can readily be seen, use a pencil ; if the floor is 
an old one (it should be quite smooth in any case) and 
pencil marks cannot be seen, either give it a coat of 
slate-color paint or else scratch your marks in with an 
erase knife. 
The space you need on the floor is, of course, the size 
of the launch, though there are two ways of doing the 
work on a much smaller floor space. One way is to, lay 
down the forward half of the launch and then right over 
it the after half, as shown in Plate 3. Another way is 
to space the sections only one-half or one-quarter their 
real distance apart — Plate 4. Both of these methods are 
in common use where long ships are laid down. We can 
economize even in doing it our way by using the water- 
line in the sheer view as the center line for the plan 
view — Plate 5. The two plans will then overlap each 
other, but you can easily distinguish one from the other 
on a plan as large as this. The sections should be kept 
clear by themselves, as they are to be worked from a 
great deal. 
To redraw the plan, Plate 1, snap a chalk line to represent 
the base line. One foot and 8in. above this and parallel with 
it snap another for the waterline. Snap three more lines 
above and one below the waterline, 6in. apart. Then 
18ft. apart square up from the base line two perpendicu- 
lar lines 4ft. long. Square up the section lines at their 
respective distance as given by the measurements on the 
plans, or in the table of offsets. Reverse your square 
when marking out these vertical lines to prove that each 
is exactly square with the base. 
If you have some one to help you, you can lay out 
the spots from the measurements given quicker than if 
you try to do it alone. The advantage of doing it all 
yourself, however, is that you are sure it is right when 
done. To take the assistant's place drive a wire nail at 
the intersection of each section line with the base line. 
These nails will be as good as another man holding the 
end of your rule exactly to the base line while you mark 
off the required distance. 
The bottom edge of the keel being a straight line, can 
be snapped in with a chalk line. The sheer line, or top 
edge of the boat in the side view, is the next line to draw. 
Measure the heights of this line off on the floor as given 
on the plan, 3ft. ioin. at bow end, 3ft. 6%in. at section 
1, 3ft. 2%in. at section 2, etc., and drive a 2in. nail into 
each spot. Draw your large batten up against these 
nails and hold it by as many nails back of it as is neces- 
sary to make it bend fair around them. 
The object in doing this is to determine whether these 
various heights are in such a relation one to the other 
that a batten may be bent in a fair curve around them so 
that when planks are bent on in the actual building, there 
will be no unfair "humps or hollows." It is the eliminat- 
ing of all these that gives this process its name of "fairing 
up." By carefully sighting along this batten, keeping 
your eye low and at one end, so- as to foreshorten and 
thereby exaggerate any unfairnesses, you can. correct 
them, letting up a little where any nail produces a hump, 
or else putting more nails to hold it as the case may 
require. Do not leave the ends of your batten loose when 
you come to the ends of the boat, but be as careful to 
continue the curve in the batten clear to its end as any- 
where else. You will .find upon trying it, that the released 
batten end will affect your curve some distance inside the 
last nails. 
Measure off the half width, using the waterline as a 
center line for the plan view, and draw that line in. Draw 
the sections on a clear space on the floor, making any 
corrections in heights or widths that the fairing up of 
sheer and deck line may have made. You will have to 
use your small y&in. batten for these sections. When 
all is laid down full size, just as is shown on the small 
plan, • you are ready to go forth .into new fields, to lay 
out the lines which, as a builder, you need to show you 
how to cut out the keel, stem, stern, etc. The designer 
now steps aside and the practical man in overalls takes 
command. 
He immediately says, "Why, this plan is (irawn to the 
