25-Foot Cabin Cruiser Part III
The keelson can now be gotten out and fastened in position. For this you will require a piece of oak, or yellow pine, 2x4 inches, 12 feet in length. Trim the forward end so that it fits the scarf in the stem, and bend to the frames. If any of the frames at the forward end have a tendency to keep the keelson from bearing tight on the frames and floors directly over the keel, you will have to trim the keelson and when you are satisfied that it fits properly, proceed to fasten it, using through fastenings at the forward end and at each alternate floor.
The bilge clamps can be fitted and fastened to the frames before the planking is fitted, and it would be as well to do this part next. The specifications call for the bilge clamps to be of yellow pine 1 1/4 x 4 inches amidships, tapered to 1 1/4 x 3 1/2 inches at the ends. This taper should be about 7 feet in length. Select some straight grained piece of stock and have it milled to the required dimensions, and finish with a hand smooth. Mark on the centre frames the location of the bilge or clamp on either side, also the stem and stern, bend the bilge clamp down in the centre and fasten with a screw clamp and then work the ends to the required position, or as a good bearing on the frames, bore and fasten to the frames, putting one fastening through each frame at the upper and lower edges of the clamp. These fastenings should be either riveted or clinched over the frames. Having fastened in the two bilge clamps, you can continue your planking and I would suggest getting out the garboards first. You will proceed in a manner somewhat similar to getting out the sheer strake, but owing to the fact that this is more difficult, I will explain it so that you can proceed without any trouble.
Take a piece of pine or cedar about the same dimensions as your spilling batten or staff, but don't use that one as you will need it for the balance of the planking; tack this over the frames close to the rabbet in the keel, take your compasses, and setting them to a radius of about one-quarter of an inch more than the widest place between the rabbet and the edge of the staff, strike in a number of arcs at intervals of about one foot apart until you get to the short turn at the stem, where the marks should be quite close in order to get the shape more accurately. Make some marks on the keel and batten in order to enable you to get the batten back in the same position again. Fig. 10 shows the staff in position with marks showing the spilling, and if these marks are transferred to the piece of plank to be used for the garboards in the same manner as suggested for the sheer strake, there will be no difficulty in making them fit, but it may save you some lumber as well as considerable labor if you first cut the spilling batten to the mark you have made, pare and trim until it fits the rabbet perfectly, and then it is no trouble to mark around same with a pencil, and you have the shape of the lower edge of one of the garboards. The shape of the other edge is obtained in the same manner as the lower edge of the sheer strake, mark the greatest width, the width at the forward and after ends, and a couple of intervening places if you so desire, bend a batten to same, strike a fair curve and cut to shape.
How Chain Clamp Is Used
You will have to exercise considerable care in fitting the lower edge to the rabbet, chalk the inside of the rabbet, and when you have clamped the garboard in position, if there are any places where it needs trimming to make a good fit, don't slight it, but spend time enough to have it fit all along the rabbet. Mark on a board a duplicate of the plank, cut and fit as carefully as the first one and, when they are ready, steam them well and start to fasten one of them, beginning at the stem. Drive the plank tight into the rabbet, bore a hole 3/8 or 7/16 inch diameter, to take the wood plug to cover the head of the fastening. This should not be over 1/4 inch deep; then bore a hole a trifle smaller than the nail through the planking into the stem, and fasten with galvanized boat nails. The fastenings should be about 1 3/4 inches apart where the garboard connects with the stem and in the keel they should be about 3 1/2 inches apart. There should be three fastenings in the width of the plank at each frame and floor, two of the fastenings to be through the frame and one through the floor, unless you make the after end very narrow, and in that case you would not need more than two fastenings at each frame and floor. When you have finished fastening the garboards, you can proceed to get out the next plank; cut to shape and fasten to the frames, etc. Before you continue to plank any further, I must call your attention to the planks which are to be used around the turn of the bilge. These planks should be cut out of stock that is thick enough to allow of the inside being coped or planed hollow to fit close to the frames. When you have removed sufficient of the inside of the plank to admit of its fitting closely to the frames, set your gauge to 3/4 inch and run a score along the edges of the plank, then plane to this line, but not for the entire width of the plank, as you can easily plane this when you finish the outside of the planking. You can now cut out and fasten in position the next five strakes, and when you have finished with them you will be ready for the shutter, for such is the name given to the last plank to be fitted. It is necessary to take a spilling on both sides for this plank, and be sure to get it large enough. Having satisfied yourself that it is the required shape, fit the forward end to the rabbet in stem and drive it in place, fasten to the stem and continue to drive it in till it fits close to the frames and fasten to same as fast as you drive it in place, for in this manner you will prevent it from springing out when driving. The cutting of the after end of the plank to fit the rabbet in the transom must be done before the fastenings are put in the last few frames; finish fastening in frames and transom and fit the shutter on the opposite side. A well-fitting shutter tends to tighten up all the planking, and it you have kept the widths of the planks about equal, it is hard to distinguish the shutter from the other planks. The planking of the raised sheer can now be gotten out and fastened in position, and as I have already explained how to obtain the shape of the planks, there is no need for me to explain the operation as there are but three planks to be gotten out for either side of the raised sheer. I have figured that all the planking you will use will be full length, but for the benefit of those who are unable to procure the long lengths or prefer the shorter planks, I would state that the method of planking would be the same, the only difference is that some of the planks would be in two or more pieces. All that is necessary is to make the butts come between the frames and fasten them securely. Fig. 16 shows the usual method of fastening a butt. The butt block should be of oak about 1 inch thick and of sufficient width to lap over the edge of the plank on either side 3/8 of an inch. The forward and after ends of these blocks should be chamfered on the side nearest to the inside of the plank so as to allow any water, that might leak in to run through, instead of collecting on top of the block.
Fit all blocks tight between the frames, and if properly fastened, the plank is stronger at this point than elsewhere. If you have butts in the planking, bear in mind the necessity for distributing same. Do not make one butt come directly over the top of another, but break all joints by placing at least three planks between, if the butt is between the same frames.
Detail Drawing of Rudder
When you have finished planking the boat, take a jack plane and roughly plane the outside, then the boat is ready for calking. It is much better to have this done by a man who makes a business of it, as there is a great deal more in calking a boat than merely driving in cotton. If you desire to try your hand at this, you should procure some good spun cotton. You will also need some calking irons and a mallet — one of these irons will be needed for opening the seams and the other for driving in the cotton. Look carefully over the seam you intend to calk, and if you decide that it is open enough to drive, in the cotton, select a piece and start it in with the iron, using the calking mallet to strike the iron. Do not stretch out the cotton and drive it in, but bring it back a trifle, then drive; keep on doing this — it makes a lap and thus makes a much thicker bunch to drive in. Set it down hard and keep it about 1/4 of an inch below the surface. Experience will help you more than any explanation I can give you, and you will find as you progress just how much cotton to put in the seams, and how hard to drive it. If you want to find out just how easy, or how difficult, it is to call a boat, just watch some of the men calking a small yacht or vessel, then go back and try it. When you have the hull calked, the seams should be painted with a thick lead paint; a long narrow brush with short bristles, known as a seaming brush, is the best thing to use to run the paint in the seams. This painting of the seams makes them hold the putty and also form a ridge which prevents the cotton from working out, as it would have a tendency to do when there is much jarring on the boat such as would be occasioned by riveting in the deck clamps, etc. The deck clamps and raised deck glimpse can now be gotten out and fastened in position. The clamp is to be of yellow pine, 1 1/4 x 4 inches, the upper and lower edges to be chamfered from the forward end to the bulkhead at the after end of the cabin. Set the upper edge of this clamp the same height as shown on the construction plan and fasten to the frames. It is a good plan to fasten through the sheer strake, frame and clamp, at each frame, setting these through fastenings alternately at the upper and lower edges. The raised deck clamp is to be of yellow pine 1 1/8 x 3 1/2 inches. Chamfer the lower edge and fasten in position. Take care to have the upper edge of the clamp at the correct height for the entire length, and when you have put in a few fastenings it is advisable to ascertain that the upper edges are true and the same height on both sides of the hull, and if so, you can finish fastening same, adopting the same method of through fastening as suggested for the clamp at the normal sheer. If you intend to finish the exterior of the hull before doing any work on the interior, you can proceed to get out the two knees for the stern; these are to be cut from oak plank 1 3/4 inches in thickness. Fit a piece of oak 1 1/4 x 1 3/4 inches across the inside of the transom at such a height as to catch the ends of the deck plank, and then fasten the knees in position, securing same to the clamp, sheer strake and transom.
You will note that there are but three deck beams shown on the plan; these are to be of oak, sided 1 1/4 inches, moulded 1 3/4 inches, and cut with a crown 1 1/2 inches in 5 feet. Mortise the ends of the two forward frames into the clamp and fasten to same. The after beam is to be halved into the knees and fastened. Between the two after beams you can fasten a piece of oak 8 inches wide and 1 3/4 inches thick to receive the lower end of the towing post or bitt, and then proceed to plank the deck. You will need some nice, clear white pine for this plank, and unless you can obtain the pine already cut with the edge of the grain on the flat side of the plank it will be best to purchase 2-inch plank and have it sawed and planed to the required thickness. The edges should be planed so as to have a bevel of 1-16 inch on each edge, and when these planks are placed edge to edge it will show a seam of about 1/8 inch in width. Draw a line through the centre of the beams, and after cutting the end of one of the pieces of plank to fit the transom, bring the edge of the plank to the line and fasten. Add planks on either side until you have the entire deck covered, taking due care to draw them close together. Calk the seams, and pay them with thick lead paint. The filling of the seams with white lead putty and planning the deck can better be finished when you have the boat nearer completion.
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