Use these notes in conjunction with the plans and the plan's building notes.

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1 GF18 CNC kit notes. Use these notes in conjunction with the plans and the plan's building notes. The standard kit is based on the GF18 with the sole option, central bench included. There are small differences between the kit and the plans, see below. The kit uses notches: frames, bulkheads and stringers are assembled like a puzzle. This automatically locate the frames and molds without measuring. The notches are not shown on the plans. The stringer are made of 2 layers and the seams are offset. The offset is not shown on the standard plans nesting. Each stringer is made of a first layer with a long tip epoxy glued to a second layer with a short tip. The plans show a large opening in bulkhead A. We do not cut that opening in the kit in case the builder wants access from the top instead. Same for the bow stringer. The bow stringer is the longitudinal frame under the casting deck. The plans shows an opening in it but we leave that cut to the builder in case he wants for example, a fish box on one side and storage on the other. Since the kit includes the sole option, there is sufficient plywood to use 12 mm ply for the floor frames instead of the 10 mm shown on the plans. The same applies to the motor well sides: they are made from 12 mm in the kit. The nesting on the plywood is different: the plans show the nesting on standard plywood sheets 96 long but the kit is cut from metric plywood sheets that are about 2-3/8 longer. Other differences are due to the thickness of the CNC router bit and CNC machine requirements. Some parts are oriented differently than on the plans nesting, see the arrows showing bow and stern side, sheer side etc. The kit uses throw away MDF molds that are not shown on the plans. Please do not compare the parts dimensions from the kit with the plans: the kit is cut directly from the 3D model and is more accurate than the plans. Since the plans dimensions are shown with a tolerance of + or 1/8, this may result in a maximum deviation of 1/4. Those very small differences are totally irrelevant and impossible to see on the finished product. Some sharp tips are rounded to a 1/4 radius, for example on the stringers. It does not make sense to have a sharp end that the builder must round later to fiberglass. Any very sharp tip would break during the assembly but the plans must show them to draw the curves correctly. Along the chine, the panels are pre-drilled for the stitches. This guarantees a perfect alignment. We drill one every 12, feel free to drill more holes in between or not to use them all. We skip a few holes that interfere with the fiberglass splices. Panels preparation:

2 Identify all your plywood and MDF sheets. See the PDF files that came with the kit. We supply one PDF file per sheet plus one PDF named puzzle. PDF files naming convention: A file named GF18_H1_H3.PDF shows the boat GF18, sheets H1 and H3. H stands for Hull, M for Molds. If any, disregard the notes about open curves, those are for the CNC operator. Some of the drawings have notes like Notches are offset 0.050" all around for easy assembly. In most cases, this allow the parts to fit together tightly without excessive play. The puzzle shows how the plywood sheets line up to assemble the long panels but use the arrows to assemble the parts, some are mirrored. You can't go wrong, the mating edges must match. The GF18 hull panels are made from parts spliced together, see the plans building notes. Assemble your stringers, transom, clamping board and long panels. Stringers are made of 2 layers. The seams between the two layers are offset. The transom is made of 3 layers. Offset each layer by about 1/4 at the bottom to follow the bottom angle. This will reduce the amount of epoxy putty required to fill the gap at the bottom. Assembly sequence : The GF18 kit is assembled on a jig, upside down. There is no need to measure anything: the location of all frames, bulkheads, molds, stringers etc. is set by notches or by the parts them self.

3 The suggested strongbacks size is 2x6's, 14' long, spaced 24-5/8 between their outside faces. You can space them differently but beware of interference with the side panels: close to the bow, the side panels sheer side will be lower than the strongbacks. That exact spacing between strongbacks lines up the outside face of the stringers with the outside face of the motor well sides. It will make bracing in that corner easier. The strong backs can be shorter but not less than 12' total. The working height is up to you: sawhorses make it easy to stitch and work on the side panels. At fairing time, you may want to lower the hull to reach the middle of the bottom panel. The pictures show the center lines on most parts: those panels are in one piece. We start the pair of strongbacks on sawhorses On top of the strongbacks we put bulkheads E and D, molds C, B and A. A, B and C are MDF molds. D and E are the plywood bulkheads.

4 Drop the stringers in the notches, this will locate all the molds. (the bracing of the molds is not shown on the pictures.) Install the bow stringer butted against mold A, flush at bottom side, use cleats.

5 The motor well (MW) sides are clamped to stringers outside face. They sit on the strongbacks, bottom side flush with stringers.

6 Next, the transom is fastened to the MW sides and stringers with temporary cleats. (The cleats are not shown). Check diagonals.

7 Drop the bottom panel on the jig. Install side panels: screw to transom, stitch to bottom. Install the bow transom between the sides, one or two screws in bow mold or stitches. Proceed with glass outside as in standard building notes. Install rubrail. Flip the hull with all framing in it. Protect the sheer: do not let the hull rest on the unsupported sheer. Remove all framing. Glass inside. Install inside framing. MW sides are epoxy glued to stringers. Floor frames are in 3 pieces. The center piece has tab that fits in stringer notches. Fill gaps in notches with putty and/or wedges. Build fillets between framing. Tab framing to hull. Install cleats on framing. Drop sole on framing. Tab all around. Proceed as in standard building notes for seats, benches and decks.