A CAD render of the assembled kayak with a translucent deck showing hundreds of small blue brackets and orange ribs inside

Composite hull designDrawing 31 of 43

Basalt fiber
kayak

A sea kayak made of 210 flat basalt panels. The brackets that lock them together are cut from the same sheet, so the boat works as its own jig. Right now it's a solid model and twelve sheets of cut files, and nothing's been cut yet.

StatusDesigned, cut files issued. Not built
MaterialBasalt fiber laminate, 1.0 and 2.0 mm sheet
Parts722 across 12 sheets, 1062 cut-outs
What does not existA boat. No panel has been cut

Sheet 02 of 10/Origin

The pencil sketch

The only physical thing this project has produced is a pencil sketch. It shows the plan view, the cockpit opening marked in red, and a little section sketched in the corner.

A hand drawing on white paper of a kayak in plan view, hatched at bow and stern, with a red outline marking the deck opening — *PL 02*Where it started, on paper, with the plan view, the cockpit opening pencilled in red, and a section sketched in the corner.

Sheet 03 of 10/The hull

Hull shape

The hull is made of 210 flat panels with two hard chines on each side, so there's no curved surface anywhere that would need a mold.

PL 04The profile, skin only. It has a low, flat sheer and a shallow rocker, because you can't bend a flat panel into a curve.

A top-down render of the untextured kayak showing the faceted deck and the oval cockpit opening — *PL 05*The plan view, skin only. The waterline is a chain of straight segments, and the cockpit sits behind the middle of the boat.

A three-quarter render of the untextured kayak hull showing the hard chine running the length of the boat — *PL 06*From three quarters ahead, skin only. There are two chines on each side, so the hull's cross section is five flat panels with no curve.

A render of a hard-chined sea kayak in olive-gold basalt laminate, seen from three quarters ahead — *PL 03*The same boat with a basalt skin. It's faceted because every panel is flat, and every facet edge is a bonded seam.

A three-quarter render of the untextured kayak from astern, with seam lines across the flat panels and a raised ring around the cockpit — *PL 22*The skin from three quarters behind, with the raised rim around the cockpit.

A low head-on render of the untextured kayak bow, with thin seam lines across the flat panels and the cockpit rim above — *PL 23*The bow head on from low down, skin only, with every seam drawn as a line.

A CAD render of the kayak hull with the whole deck removed, open from end to end, with small orange parts along the seams — *PL 20*Canoe mode, with the deck lid off, so the hull is open from bow to stern.

A render on a dark blue background of the kayak with dark seam lines and short tick marks over every panel, and lighter panels around the cockpit — *PL 24*Every seam drawn in, with the deck closed and the panels around the cockpit shaded lighter.

The same render with the lighter panels around the cockpit removed, showing the open hull and small parts along its edges — *PL 25*The same view with the panels around the cockpit removed, so you can look down into the hull.

A high three-quarter render of the kayak with the panels around the cockpit removed, seam lines over every panel and small parts standing around the opening — *PL 26*Looking down into the open hull from higher up, with the same panels removed.

A low three-quarter render from the bow on a dark blue background, with seam lines over every panel and a raised rim around the cockpit — *PL 27*From low at the bow, with the rim standing up around the cockpit.

A low three-quarter render from the stern on a dark blue background, with seam lines over every panel and the cockpit rim — *PL 28*The same render from low at the stern.

Sheet 04 of 10/The bracket

How the seams close

A flat bracket cut from the same sheet closes every seam. Its tabs push through slots in the panel, so the seam can only close to one angle.

Five hundred and five of them close all 210 panels. Each one is named after the seam it closes, so if you find a bracket on the floor, there's exactly one place it can go.

An annotated engineering figure of the assembly bracket showing the chine joint, the slot cut into the panel, a floor frame, and a table of dimensions — *PL 07*The bracket, drawn to its own dimensions. It has a tab that goes through a slot, an arm cut to the seam angle, and a stand-off that holds the fold open.

A close render of the cockpit opening with small upright plates along the seams, above a translucent lower hull in a patchy tan texture — *PL 29*Up close at the cockpit, with the lower hull drawn see-through. Small plates stand up across the seams all around the rim.

A close render of one end of the cockpit rim, with rows of small upright plates along the seam lines over a translucent lower hull — *PL 30*The bow end of the cockpit rim, closer in, with the same small plates across each seam.

Sheet 05 of 10/Floor frames

What holds the bottom up

Seven floor frames sit under the cockpit, one every 8 inches, so there's never a long stretch of the bottom panel without support.

A CAD render looking into the open kayak hull, with small orange ribs standing up from the bottom and seven green transverse frames — *PL 08*Inside the bare hull, with the 2 mm bottom, its ribs standing up in orange, and the seven floor frames in green.

A CAD render of a single green triangular floor frame seated between two grey hull bottom panels, held by four orange tabs — *PL 09*One floor frame on its own. It's a shallow vee spanning 16 in, tabbed through the bottom, with a limber hole at the keel.

Sheet 06 of 10/Skin

Skin thickness

The bottom panel is 2 mm basalt, because 1 mm isn't strong enough to sit on. Everything else on the boat is 1 mm.

Sheet 07 of 10/Cut files

Twelve sheets, 722 parts

The cut files are twelve sheets, with 722 parts and 1062 cutouts. Every outline is read straight off the solid model, and nothing was drawn again by hand.

Six lid panels come out as slivers about 0.8 by 0.1 inches, which is too thin to cut. So the plan says to tape the gap and wet it out instead.

A wide nesting diagram of twelve rectangular sheets packed with hundreds of numbered kayak panels, ribs and brackets — *PL 11*The whole boat laid flat on twelve sheets of 22 by 44 in laminate. Every outline and every hole is read straight off the solid model.

A detail of the cut plan showing sheets one to three of 2 mm stock, with large triangular hull bottom panels labelled H000 through H036 — *PL 12*The three 2 mm sheets, close enough to read. Every panel has its own name on it, and the note in orange is about a known defect.

A detail of the cut plan showing two sheets densely packed with hundreds of small orange bracket outlines — *PL 13*The last two sheets are almost all brackets. Three hundred and sixty-eight of the 505 brackets nest on just these two.

A dense multi-column table listing each bracket by the seam it closes and the sheet number it is cut from — *PL 14*The full assembly key. It lists every bracket, the seam it closes and the sheet it's on, so if you find a part on the floor, you can look up where it goes.

A nesting diagram of nine rectangular sheets packed with numbered grey triangular and rectangular panels — *PL 31*An earlier nesting with only the skin panels, on nine sheets and a 0.25 in gap between parts.

A nesting diagram of ten sheets in two rows packed with numbered grey panels, the last sheet holding a row of thin slivers — *PL 32*Another earlier version, with all 210 panels on ten sheets of 1 mm basalt and a 0.20 in gap.

A detail of a cut plan showing sheets one to three, with long panels and triangles outlined in black and small orange and blue parts fitted in the gaps — *PL 33*Part of an earlier plan with 210 skin panels and 300 assembly ribs on ten sheets of 1 mm.

Sheet 08 of 10/Material

Basalt or carbon

I rendered a basalt version and a carbon version from the exact same 722 parts. The only difference is the sheet that goes into the cutter.

A render of the kayak in olive-gold basalt laminate seen from three quarters astern — *PL 15*The basalt version, seen from behind. It's olive-gold, and it's the reason the boat is named after its material.

A render of the same kayak in dark grey carbon laminate seen from three quarters astern — *PL 16*The carbon version from the same angle. It's the same geometry and the same 722 parts, with a different reel loaded into the machine.

A close render of the kayak cockpit opening in basalt laminate, with a raised coaming ring and small slots visible in the deck — *PL 17*The cockpit rim in basalt, up close. The dashes around the opening are the bracket slots, which are cut into the panel before it folds.

A close render of the same kayak cockpit opening rendered in dark carbon laminate — *PL 18*The same rim in carbon. The fiber you pick changes the cost and the look but leaves the drawing the same, so there are renders of both.

A render of the hard-chined kayak in dark grey carbon laminate, seen from three quarters ahead — *PL 34*The carbon version from three quarters ahead, with the same flat facets as the basalt one.

A low head-on render of the carbon kayak bow showing the vee bottom and the dark cockpit rim above — *PL 35*The carbon bow head on from low down, to compare with the basalt one.

Sheet 09 of 10/The paddle

The paddle

There's a slot on this page for a Greenland paddle, but nothing for it has been drawn yet.

REF 21Greenland paddle, general arrangementassets/projects/basalt-fiber-kayak/21-greenland-paddle-general-arr.webp

Sheet 10 of 10/Status

Where it stands

It isn't a boat yet. No panel has been cut and no seam has been bonded. The next real step, before committing to twelve sheets, is to bond one seam on scrap and see if the numbers hold up.

A low head-on render of the basalt kayak bow showing the vee bottom and the two chines meeting at the stem — *PL 19*Looking at the bow head on, from waterline height. A paddler never sees this section, and it's the one that decides whether the boat tracks straight.

Basalt fiberkayak