CHAPTER XXVIII. SOMETHING ABOUT FRAMING THE BOAT-HOUSE.
While the work of framing the boat-house was in progress, the lessons in the shops were suspended, but the forenoon exercises of the school were continued as usual. The new tools had arrived, and had been distributed. The place chosen for framing the building was a level piece of ground between the shops and the dormitory.
On this spot the timber had been landed and piled up by laborers. Instead of assembling in the shop after dinner, the students were required to be on this ground with their boxes of tools. Mr. Brookbine was the central figure of the picture on this occasion, and, as usual, the boys were full of enthusiasm, for they were to make a beginning on a new piece of work. They gathered around the master carpenter, each standing by his box.
"The difficulty in our way, boys, is that you insist upon going too fast," Mr. Brookbine began. "Captain Gildrock wants it understood that our business now is not so much to frame a building as to learn how to frame one. I am willing to answer questions, but I want you to stick to the text, and not talk about things a thousand miles from it.
"This boat-house is to be ninety-six feet long and thirty-two feet wide, not including the lean-tos for the dressing-rooms and small docks. We will divide the length into six parts, and the width into two parts. This will make twelve squares of sixteen feet each, or two hundred and fifty-six square feet. Every corner of these twelve squares must be supported by a foundation."
"That will make forty-eight posts, and only thirteen have been ordered," said Life Windham. "I don't see how thirteen posts can support forty-eight corners."
"Perhaps if you had waited before you said anything, you would have seen. Each of the inside posts, in the middle of the platform between the docks, will support four corners. One post may support one, two, or four corners. Of course no posts are required for those parts which are over the shore. We shall simply put blocks or short pieces of timber under them, and lay stone wall under the sills."
"But what are the sills?" asked Tom Ridley.
"I will explain the details as soon as you get the general idea of the frame," replied the instructor. "As I have said, the space to be enclosed by the frame is divided into six sections of the whole length. Each of these sections contains two of the squares I have described. Now, Ludlow, give me the size of the ground of each section."
"Thirty-two by sixteen," replied the student indicated.
"Right; and the boat-house will be the same as six buildings of thirty-two by sixteen, though all but two of the sides would be common to two of them. What I shall call a section of the frame includes all the timbers in one end of the building. I say one end. Never mind the length of the building. How many of these sections of the frame will there be, Bellows?"
"Six, of course," replied the student; and about half the boys laughed outright.
"Wrong," added Mr. Brookbine, joining in the laugh. "We have had this subject up before in the shop, and I am sorry you have forgotten about it. If you set up six stakes in the ground, how many spaces are there between them, Bellows?"
"Six, I should say;" and the boys all laughed again.
"Set them up and count them," continued the master carpenter, rather impatiently.
Ned Bellows did so, and could count only five spaces. He was required to add another stick, and this gave him the six spaces, as in the building.
"How many stakes have you, Bellows?"
"Seven," replied the student, rather sheepishly. "I see that there will be seven sections of the frame."
"Making no allowance for the docks, these seven sections are just alike, and contain precisely the same timbers," continued Mr. Brookbine. "This frame will be put together in sections, and each will be raised by itself, by the aid of rigging and machinery."
The boys began to ask questions, for some of them did not understand the sections yet. The instructor sent for a blackboard, which he placed on an easel; and with this he made the subject plain to all. There were seven tiers of timbers to be set up, when framed and put together, just like seven bricks, each placed on one end.
"Now we will drop the sections for a time, and take them up again when we are ready for them," the instructor proceeded, as he rubbed the drawings from the blackboard. He then drew an outline of Chowder Point and the shore near it. "Now I will mark where the twenty-one points of support of the building are to be placed;" and he put this number of small crosses on the board. "Some of these bearings are posts and some are blocks, as they are in the water or on the shore.
"The timbers which rest on these foundation-points are the sills. These are the first we frame. They are twelve inches square. We cannot find any in our pile ninety-six feet long, and we shall have to scarf or splice them." While he spoke, he drew the positions of the sills on the foundations.
"But the boats can't go through that timber to get into the docks," interposed Nat Long.
"Let us attend to the general plan of the frame, and we will alter it for the docks before we are done," replied the instructor, as he proceeded to draw the five cross-timbers connecting the sills. "Now the sills are laid down. Between the cross, or section sills, we put in the floor joist. How far apart are the sections, Gawner?"
"Sixteen feet."
"These floor timbers are simply two-inch planks, nine inches wide. There is a pile of them," said Mr. Brookbine, pointing to the lumber. "They are to be placed sixteen inches apart, the sills being notched, or mortised, to receive the ends. These joists must be bridged."
"Bridged?" queried Ben Ludlow.
"This must be done before the floor is laid, for we can't get at the joist afterwards. Short pieces of board are nailed from the upper side of one timber to the lower side of the next one, the ends being sawed at the right bevel. Another piece is nailed in close to it, at right angles with the first. A pair of bridge-sticks must be put in every five feet. They are used to prevent the narrow timber from canting, thus giving a firm and solid floor.
"The next thing is to lay the floor; that is, we nail down boards over all the timbers. This will make the lower floor. Now, I may say that the framing for the end of the building where the docks are must be adapted to their shape. The floor-timbers of the lean-tos for the dressing-rooms will be supported by braces above and below from the posts.
"Now, we will suppose that the entire floor, except the docks, is laid, and we have a platform ninety-six by forty to stand upon. Before the sills were put in place, they will be mortised to receive the tenons at the ends of the posts, and of the braces. Now we are ready to return to the sections of the frame.
"To each section there are three posts,—one at each side, and one in the centre of the building. On the upper ends of these posts rest the plates;" and the instructor drew the parts as he described them. "They connect the posts at the top, as the sills do at the bottom. About on a level with the hall-floor are timbers, called girders, joining the middle post with the outside ones. The sills, the plates, and the girders are the principal timbers, and are the same in all the sections.
"In every corner there is a diagonal brace, forming a right-angled triangle with a base and a perpendicular of three feet. We shall mortise for these braces, though of late years many carpenters simply spike them in their places. Between the sills and the girders, and between the girders and the plates, are the studs. They are made of four-by-two stuff, or, in other words, of two-inch plank, four inches wide. The sills, girders, and plates are mortised for them, and a two-inch tenon cut at the end of each stick. Where windows come, short studs are put in above and below them. They are placed sixteen inches apart. This completes the frame below the roof."
"Then we are ready to go to work," said one of the boys.
"Not yet, for you don't expect the sections to stand alone. The frame of the first section will be put together with the bottoms of the posts at the mortises they are to occupy. It will be no easy job to get it up to a perpendicular; but it can be done with pike-poles and a derrick, with no little rigging. When we get it upright, the tenons will drop into the mortises, and we have to stay it in position with braces and ropes. Then we raise the second section in the same manner. There are plates and girders on the sides as well as the ends of the building. While the two sections are held in position, the girders and plates are put up to connect them. The studs and braces are put in place, as in the end section.
"All the large timbers are pinned together. You will have a nice time in making a cord or two of these pins. They are about an inch in diameter, made a little large for the hole, so as to fit it snugly. We pin the braces so that they will hold both ways, but the studs are not fastened at all, for the tenons cannot get out of the mortises."
"We can turn the pins," suggested Lick Milton.
"You can; but while you are fitting the wood into the lathe I can cut out two of them with a broad axe. Your eye must be educated to the size. As we add each section to the building, we fill in the space between this one and the next. Now we have the frame up all but the roof.
"All structures are not framed alike, and some of the connections I have mentioned have to be omitted in some places. For example, the braces between the cross-girders and the posts can be used only in the ends of the building. Again, all the middle posts, except the two at the ends, must be short ones, for we don't want them in the middle of the hall.
"The framing of the roof is a simple matter, though we shall have to support the ceiling of the hall from it. To do this we use a little larger timber than would otherwise be required for the rafters, as they form a sort of truss, from which we hang the upper floor. I have finished what I had to say; but the details will have to be explained as we go along."
"You can't do anything with some of these timbers," said Bob Swanton, as he pointed to one near him. "It is twisted all out of shape."
"That one is warped in the sun; but a stick must be very crooked before we throw it out," replied Mr. Brookbine. "We must take the 'wind' out of it. All we want is two faces at right angles with each other. We select the two best sides, and with a couple of squares sight along each. Then we must hew it down where it is out."
The students were then required to take the square and compasses from the box. The actual work of framing was to begin.