THE STUDENTS USE THE SQUARE AND COMPASSES.
Mr. Brookbine stood on one of the timbers intended for the sills of the
boat-house. In his hand he held a steel square and a pair of compasses.
"The pair of compasses I hold in my hand," he said, "are of the simplest
construction. Those you have in the shop are fitted with a screw-stop so
that you can fasten them in any required position. You will complain
that it is hard to move the legs of these, but as they must stay in
place without any screw, it is necessary that the joint be a tight fit."
"Legs?" said a student.
"You can call them shanks, if you prefer, or arms. There are a great
many technical names to parts of apparatus which are not often used
because they are not generally known," replied the instructor. "Since I
came to Beech Hill I learned that an oar consists of the handle, the
loom and the blade. Outside of the navy probably not one in ten ever
heard of the loom of an oar, or would know what it meant. In carpentry
the technical names used in one part of the country are not known in
other parts. Legs is the proper technical name of the two parts of the
compasses.
"You notice that the points are more blunt than those you use in the
shop. In framing we use one of the legs as a marking-awl. The awl would
do just as well, but it is sometimes convenient to have the compasses in
your hand so that you can lay off a distance from the square with them.
The points are tapered more rapidly so that they will make a mark which
can readily be seen by the workman.
"The steel square is one of the most important tools used by the
carpenter, and I could use up hours in telling you about it. The parts
have technical names, though few make a strict use of them. The corner
is called the heel, from which each of the four measures on it start.
The long arm is the blade and the short one the tongue. The blade is
just two feet long, or twenty-four inches."
"Mine is only twenty-three," suggested one of the boys, all of whom were
examining their steel squares.
"Mine is only twenty-two in one place, and twenty-three in another,"
added another.
"You are altogether too literal, and the letter killeth in carpentry as
well as in Scripture," replied Mr. Brookbine. "You must apply common
sense to the figures. Now look at the outside measure on the blade: find
the figure for one inch. That one means one inch in length, without
regard to breadth, as you define a line in geometry. Hold up the square
with the tongue down. Now does the inch of length lie on the right or
the left of the point marked one."
"On the right," replied a dozen.
"Now look at the point marked twenty-three: is the inch marked with this
number on the right or the left of it?"
"On the right."
"But there is another inch on the left of the mark, which is the
twenty-fourth inch, though there is no room to mark it uniformly with
the other numbers. Now, boys, look the thing over a little before you
raise an objection. I repeat that, on the outside, the blade is two feet
long. The student who said his blade was marked twenty-two in one place
was wrong in his fact, and if he looks again he will see that the
inside length of the blade is twenty-two and a half inches, which is
the outside width less the width of the tongue.
"In these squares the tongue is sixteen inches long, on the outside, and
fourteen on the inside, marked in the same manner as the blade. The
inside length is two inches less than the outside, for the blade is two
inches wide, while the tongue is only an inch and a half. You must know
the square so that you can use it without stopping to study out its
meaning.
"The tongue is sixteen inches long in this instance because it furnishes
a convenient measure for the placing of studs and furrings. The rule is
to put studs and furrings sixteen inches apart; but there is no law
which compels any carpenter or architect to follow it. Floor-joists are
usually placed at the same distance apart, though the rule is often
varied to meet the circumstances."
"I don't know what a furring is," said one of the boys.
"Furring a house is nailing strips of board, usually sawed at the mill
three inches wide, to the posts and studs for the sides, and the
floor-joist for the ceiling, on a room, at a distance of sixteen inches
apart, on which the laths are nailed for the plastering. If they were
placed at any other distance from each other, it would make great
confusion and waste in lathing. Laths are sawed four feet in length, so
as to cover the space from the middle of one furring to the middle of
the third one from it. Each lath is nailed to four furrings."
"But every room can not be exactly divided into spaces of sixteen inches
in its length or breadth," suggested Harry Franklin.
"Very true; but the sixteen-inch division is used as far as it will go,
and the lather must cut his laths for the last one. All the confusion
comes in at the end then. If any other division were made he would have
to cut every lath he used."
"But I have seen furrings only two inches wide," Lew Shoreham objected.
"No matter whether they are one or six inches wide: the rule is
followed. But sixteen inches means from the centre of one furring to the
centre of the next one; and the difference in the width comes into the
space between them. In some places they lath upon the studs, inside, and
clapboard upon them on the outside, without boarding.
"There is no particular reason why the blade of the square should be
two feet long, except that it is a convenient length. The width of both
the blade and the tongue is important. In mortising the sill for the
studs, we shall cut out a square hole of an inch and a half, which is
the width of the tongue. We will begin with the timber on which I am
standing, which is a foot square. The posts will be eight inches square.
Baxter, measure four inches from the end.
"This point will be the centre of the mortise for the post," continued
the master carpenter when the students had marked the distance. "Now lay
off sixteen inches, and stick the point of the compasses well into the
wood so that we can see the mark. This is the centre of the mortise for
the first stud. The stuff for the studding is four inches by two. Set
the points of your compass one inch apart, and keep them so for the
present. Lay off one inch on each side of the point you have made in the
sill."
Baxter did as he was told, and the rest of the students watched him.
"The space between the outside points is two inches, just the thickness
of the stud," continued Mr. Brookbine. "Put one point of the compasses
in either outside hole you have made; rest the tongue of the square
against the leg; let the blade hang over the side of the timber just far
enough to enable you to square across the upper face of the timber;
scratch a line across with the point of the compasses; in other words,
scribe it. Do the same with the other outside point. Now you have the
length of the mortise marked on the timber.
"Place the tongue of the square against the outer face of the sill, its
length just even with the corner, and be accurate about it. Good! Now
scribe against the inside of the tongue. Move the square until the
outside of the tongue coincides with the line just made, and scribe as
before. The result is that you have ruled off the width of the tongue,
an inch and a half, at the same distance from the corner of the stick.
This gives you the other two sides of the mortise. You must measure,
mark, and scribe accurately, or our studs will not come in the right
place.
"Now we will take a piece of studding, and finish the subject. The
mortise will be an inch and a half deep, and we are to mark off a tenon
to fit it. Set the square at the width of the tongue from the end of the
stick, scribe all around it. The thickness of the stud fits the mortise,
so that we have to cut away none of it. Place the tongue against the
face of the stud and scribe it. Do the same on the other side. Place the
tongue against the mark made and scribe again. You may scribe in the
same manner across the end of the stud. The result is that the tenon of
an inch and a half by two inches is marked off at the distance of an
inch and a half from the face of the stick. You can see that nothing but
the saws are required to do the work."
"We can do all that fast enough," said Ben Ludlow.
"The trouble is that you will do it too fast, and be careless about it,"
replied the instructor. "It requires sound judgment to do this work
well. As I have told you before, one may waste his wages ten times over
in cutting up lumber. Before you put the saw into a stick, you should
consider what the piece you cut off is good for. Most of the timber is
selected for the frame, so as to make the least waste. I shall have a
great deal to say to you on this subject as we go along. No matter how
much money you have, or who pays the bills, there must be no unnecessary
waste. That he cuts stock to good advantage, is one of the best
recommendations for a mechanic."
"Don't we have to fit the tenons to the mortises, and number them, or
something of that sort?" asked Luke Bennington.
"Some carpenters frame in that way, which answers very well in a small
building," replied the instructor. "We shall use in the boat-house
between four and five hundred studs, for example, and it would be more
work to number and find them than it would be to frame the whole of
them. We shall frame by what is sometimes called the square rule. Any
long stud will fit any place where a long stud is required. The
jack-studs, or short ones, are of different lengths, and we classify
them by their size. Of course the short posts cannot be used in the
sides or ends, or the side posts at the corners; but all the sticks of
the same class are interchangeable."
The master carpenter ended his lecture. The timbers for the sills had
been laid out for framing, and under the direction of the instructor,
the students proceeded to mark them off for mortising. It would require
a whole series of books to follow him in all the details. In what manner
he gave his instruction has been shown. Four students were instructed
how to mark for the posts, and they proceeded to do it.
Four more were told how to mark for the tenons at the ends of the
posts, and as soon as they were fairly at them, four more were selected
to prepare the girders. A squad was put upon the braces, another on the
plates and a third on the studs. In a short time they were all at work.
Mr. Brookbine looked over the marks as fast as his time would admit. Of
course there were many mistakes, and these were pointed out.
After an hour's use of the square and compasses, the boys needed a
change of work, and the instructor called for the framing-chisels and
mallets. All hands were set to mortising where the marks had been made
and proved to be correct. The students worked hard, and when night came
they did not feel much like skylarking.
The next forenoon, while the pupils were at their studies, the master
carpenter went over the marks and measurements on the timbers. He was
surprised to find so few errors. Before noon he had arranged everything
for the afternoon. The boys worked hard, and the framing was not likely
to last long.