Deck Framing

It's a great day indeed when you remove the molds. But don't be in too great a hurry; a few things need doing before you break them loose.  I assume that you've been properly cau­tious, with ties across from sheer to sheer in the middle third of the hull (to prevent spreading) and braces between frames below the future location of the sheer clamp in the ends of the vessel, where she'll try to come together. You should mark a true, pure line, representing the underside of the covering board, identical port and starboard, on the sheerstrake, with due allowance for the crown of the deck. The sheer marks on the molds will help you get this right. Dress off the sheerstrakes to this line.  Be sure to run a pencil line down the inside of the planking, along the business edge of each mold. If you haven't yet followed my instructions in Chapter 11, I wish you'd roll a strand of cotton into the topside seams, and even do some smoothing above the turn of the bilge, to calm the visitors, but I'm afraid this is too much to expect-so go ahead and yank the molds out. As soon as you've finished gawking at the vastness of that hold, we'll consider the problems of the deck frames.  In its simplest form, the deck frame consists of beams extending from side to side of the vessel, usually spaced about the same distance apart as the hull frames-with various open­ings left for houses, hatches, cockpits-and damned well fastened at both ends to resist the weight of years and boarding seas. This end fastening has taken various forms through the centuries, ranging from spruce-root lashings, hanging knees fastened to frame heads, mor­tise-and-tenon joints through the sheerstrake, to the system most of us now use, which I will describe here.  The sheer clamp  The first move is to fit and fasten a timber to the insides of the frames, with its top edge below the top of the sheerstrake by the depth of the beams, and extending from the stem to the transom. This is a simple enough proposition, with only two inherent pitfalls.  You'll notice the first problem (as I finally did about the third time around) when you lay your concave beam mold across the hull from sheer to sheer and mark on the inside of the frame for the top edge of the sheer clamp at that frame. If the vessel has tumblehome, plumb, or even slightly flaring topsides, that mark must be, below your mold, much less than the depth of the beam. The beam must hit the inboard edge of the clamp. In the forward sections, where the topsides very likely flare decidedly outward and the beams are short, the opposite effect occurs: the inboard edge of the clamp is higher than the outboard and must be notched to get full-width contact with the bottom of the beam. Figure 13-1 shows this effect better than I can describe it.  The second problem crops up in the for­ward part of the vessel. It's very likely that the flare of the topsides will demand a humped-up curve, which you may have noticed when you fitted the sheerstrakes. Since the clamp is to be a 1 ½- by 4½-inch timber, you are not likely to get this curve by edge-setting. Perhaps you'll have to steam it, or even saw it to shape; maybe you'll split it (horizontally, of course) with a saw cut, back to the point where the timber straightens out and starts curving in the other direction (see Figure 13-2a). The latter scheme works fine, and never mind