Skip Kovacs' Paterson 7 Jig

These shots cover the jig building process quite thoroughly. This is a male jig for vacuum bag construction. A jig for a wet layup boat would have many more battens but not the ply top layer. Comments are all by Skip, translated into English from the original American by the Webmaster :-). This appears to be an exceptionally well planned and built jig judging by some others I have seen. Built 2001.

Strongback of 1x4" timber, well seasoned then jointed 1 edge, then ripped to constant thickness so level on underside when mould is finished levels the whole jig. Cross pieces every other station.

Snout piece tied to first cross piece, all pieces filleted together.

All stations, cut from 5.4mm lauan ( or is it luaun ?)/ meranti ply. Cheap 1/2" builder's ply here is 3 ply, NOT flat. This is best / flattest in US. But too thin to screw battens to, so they're set in notches and filleted instead.

Triangular braces filleted to stations to hold upright on strongback later.

Strongback with stations filleted in place.

View from bow. Notches cut for chine battens. Always nice when the centrelines line up. Note stations do not yet have wings for flares - ply too thin so they'll be 1x3" timber epoxied on later to guidelines drawn on frames during lofting.

Clamping chine battens on. Wing / flare timber also in place. Outer battens a mistake - had to reach quite a ways to fair bottom battens later!

Noticed in later pics of Shiny Beast that Andy had put a bit of a bulge in 2676 which I really liked the looks of. Also figured it would help open the area for the kite to come into. So these pieces were lofted up and glued into place... Also pieces for snout, with lofting for pole holes.

Bottom battens let into notches and epoxy filleted in place. Battens come together at bow, where curvature is greatest, so this is solid timber, sanded to shape.

Topsides battens in place. Since topsides are flat sectioned and I used 5.4mm luaun, don't need many.

Topsides ply glued down.

3mm bottom ply on, small batten let into flares to define hull edge. Extra ply bits on snout frames to support bag-edge shelf there.

Flare ply lofted, kerfs cut through bottom to just shy of top veneer layer to allow bending around tight radius at front of flare gunwale.

Making bulge - 6mm square battens hot-melt glued to frames to define surface.

Spray 2 part polyurethane builder's foam in a can ( "Great Stuff" in US ) behind battens to fill gaps. Leave overnight to cure. Surprisingly, no battens popped / pushed off by foam expanding...

Lines drawn on bulge to help fairing. Also timber bit put in for bottom edge of snout mould. Closest line is approximate end of hull.

Bulge close to done after initial fairing with epoxy-bubble mix.

Done! bulge and flares faired with bubble mix, all ply epoxy coated and sanded, etc.

Bow / snout of finished mould

Flare / gunwale of finished mould. Line defines lofted hull edge. Ply bits faired in to support bag.

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	Strongback of 1x4" timber, well seasoned then jointed 1 edge, then ripped to constant thickness so level on underside when mould is finished levels the whole jig. Cross pieces every other station.
	Snout piece tied to first cross piece, all pieces filleted together.
	All stations, cut from 5.4mm lauan ( or is it luaun ?)/ meranti ply. Cheap 1/2" builder's ply here is 3 ply, NOT flat. This is best / flattest in US. But too thin to screw battens to, so they're set in notches and filleted instead.
	Triangular braces filleted to stations to hold upright on strongback later.
	Strongback with stations filleted in place.
	View from bow. Notches cut for chine battens. Always nice when the centrelines line up. Note stations do not yet have wings for flares - ply too thin so they'll be 1x3" timber epoxied on later to guidelines drawn on frames during lofting.
	Clamping chine battens on. Wing / flare timber also in place. Outer battens a mistake - had to reach quite a ways to fair bottom battens later!
	Noticed in later pics of Shiny Beast that Andy had put a bit of a bulge in 2676 which I really liked the looks of. Also figured it would help open the area for the kite to come into. So these pieces were lofted up and glued into place... Also pieces for snout, with lofting for pole holes.
	Bottom battens let into notches and epoxy filleted in place. Battens come together at bow, where curvature is greatest, so this is solid timber, sanded to shape.
	Topsides battens in place. Since topsides are flat sectioned and I used 5.4mm luaun, don't need many.
	Topsides ply glued down.
	3mm bottom ply on, small batten let into flares to define hull edge. Extra ply bits on snout frames to support bag-edge shelf there.
	Flare ply lofted, kerfs cut through bottom to just shy of top veneer layer to allow bending around tight radius at front of flare gunwale.
	Making bulge - 6mm square battens hot-melt glued to frames to define surface.
	Spray 2 part polyurethane builder's foam in a can ( "Great Stuff" in US ) behind battens to fill gaps. Leave overnight to cure. Surprisingly, no battens popped / pushed off by foam expanding...
	Lines drawn on bulge to help fairing. Also timber bit put in for bottom edge of snout mould. Closest line is approximate end of hull.
	Bulge close to done after initial fairing with epoxy-bubble mix.
	Done! bulge and flares faired with bubble mix, all ply epoxy coated and sanded, etc.
	Bow / snout of finished mould
	Flare / gunwale of finished mould. Line defines lofted hull edge. Ply bits faired in to support bag.