For those of you who are new to this type of boatbuilding, there is an early shock in store. Having placed the bottom plates on the jig, you may think they’re not going to fit. Keep the faith! Start tack-welding in the middle of, or somewhat aft of, the middle of the plate. Make sure the marks on the plates are lined up at all times. As you work forward and backward from the tack-welded position, you can form the plates to shape with some human help or by using a trolley jack underneath the area of the plates where they are to join. When they touch, tack-weld them together and move along to the next position.

   At the bow, you’ll probably need a block and tackle to pull the sides of the plates together. Some tension will be experienced in this area. Don’t forget to secure the positions of any clamps so that they cannot unexpectedly let go.

Having finished tack-welding the bottom plates together, start placing the frames in position on the bottom plates. Lines on the plate will indicate the location of the frames.      You may use the scale drawings as a reference. Depending on the layout of the bottom stringers on your particular design, you may have to install some of them as you are installing the bottom frames. Study the layout of the bottom framing on your boat plans and it will become apparent which sequence will work best for your hull.

   Pull up the bottom plates toward the frames until they fit snugly and tack-weld them. Start with a frame where the plates are least shaped, and work backward and forward from there. If you’ve assembled the complete frames, as opposed to the bottoms only, use temporary braces, as necessary, to support the top portions of the frames. Once all the frames are installed, you may fit some of the side stringers into the slots on the frames. These stringers will assist in stiffening up the structure at this stage. Once again: 

    Use only tack-welding at this stage of the assembly process.

   The next step is to install the side plates. This is best done by using a simple overhead gantry or a forklift truck. Pick up the side plates with a plate clamp on a chain connected to a block and tackle made fast to a forklift leg. Make sure the plate is more or less in balance while it’s hanging free of the ground before you lift it into position. Use a helper to locate a matching line in the right position and tack-weld it. Continue to move the plate up or down a bit with the block and tackle until the entire side is in position and tack-welded in place. Place some tack welds on the side frames-to-plate joint as well as on the chine seam.

   The side plates near the bow and the underside of the bow will show some tension, and can be pulled into place by attaching a chain on the outside of the plates. To attach a chain or a block and tackle to a plate, tack-weld a temporary eye or similar piece to the plate. By welding only one side of the eye, you can easily remove it after use.

Next, the transom plates, bathing platform, stern plates, and all other plates that go into forming the hull are installed and tack-welded in position. Note that with radius-chine boats, the radius panels are installed later. Remember to refer to the drawings frequently.

   Now the deck plates, superstructure, and items like a flybridge are installed and tack-welded into position. Any deck stringers and cabin top intercostals in your design may need to be installed before the applicable areas of plating. In some cases, it may be possible or preferable to tack-weld the superstructure together off the boat and then install it as one unit. Some of the more recently designed kits allow for this option by providing special landing areas at each frame, which make it simple to line up the completed superstructure with the hull and deck.

Radius Chines

   After you’ve tack-welded the entire boat together, it’s time to tackle the radius chines. We’ve always maintained that radius-chine hulls should be built upside down. For one-off boats built from scratch, this advice still stands. But, because all kit boats are built upright, a special approach is required to enable the radius chines to be fitted without blemish. At first, we supplied the radius plates rolled in one direction only; this is the same rolled plate you would use in one-off radius construction. We soon discovered why we had always insisted that these radius-chine boats should be built inverted.   Fortunately, we were able to solve the problem. The radius-chine boats built from these kits are still built upright, but with one important difference: we now supply fully formed radius plates. They are rolled in all directions to ensure a perfect fit. This improved arrangement is available because it is now possible to have the plates fully formed and rolled from the information supplied in the original modelling files. The forming cannot be accurate right to the edge of the plate, however, so each section is a little oversized at the edges, which allows for exact fitting and trimming. Your kit will contain the appropriate amount of pre-rolled, numbered sections to fit the area covered by the radius chines.

   Now you can carefully place the appropriate pre-rolled section against the position on the opening in the hull. Using a helper, scribe the edges of the plate with a sharp tool or pencil and then cut, grind, or nibble the edge for a perfect fit. Tack-weld it in position and continue until you have all the radius panels in place.

Finishing the Assembly

   The first job is to complete the welding of the frame sections and then intermittently weld the frames and stringer to the hull plating using 2-inch (50 mm) weld spaced at 6 inches (150 mm). Do not over weld and do not continuously weld on one side of the hull. Weld on a reasonable amount on one side then switch to the other side, back and forth until the entire hull is welded. Constantly working from side to side will avoid the plates pulling out of shape and general distortion that can be caused by over welding or welding entirely on one side at a time.

   You should have made a 60-degree V between the plates, 30 degrees on each plate, but if you haven’t previously prepared the heavier plates in this manner, you may do so now by running an angle grinder along the appropriate seam. Now you can proceed to run the final welds on the outside of the plates. The hull below the waterline must be welded both inside and out. Again, work from one side of the hull to the other, frequently changing sides.

   You can grind off any excess weld material by first using a coarse disk and then finishing up with a softer, more flexible disk. Take advice from your materials supplier about these items. Lastly, apply a minimum of filler to the seams and apply a coat of primer to the ground areas. You’re now ready for final finishing and painting. The remainder of the painting and fitting-out work is the same whether you build from a kit or from scratch. One big difference is that by using a pre-cut kit you’ll have saved over 75 percent of the time required to build a similar hull from scratch.