Hi all,

At last succeeded in getting a User Profile uploaded (thanks John A.) and with help from computer literate son managed to get pics embedded in a Post per previous trials. Now for the build story with pics of my YOST Sea Cruiser.

When I first spotted a pic on the Internet of a SoF being held above the head with one hand I knew I had to get/make one to replace my nice but sturdy plastic Prijon Touryak of 26kg. Unfortunately no Skin-on-Frame kayaks had previously been built on this side of the Australian continent and information on building fuselage style SoFs was also non existent locally.
The 'great man' Tom Yost was most helpful with advice on craft selection to suit my local paddling area and my aged and somewhat damaged carcase. I read and re-read Yostwerks on-line info and followed the Internet Manual fairly closely.

However I attached all 6 frames to the strongback to guarantee the design rocker was achieved and to ensure that the keelson was straight and utilised string line for all vertical measurements plus spirit levels for vertical alignment. To give a little higher sheer line at the bow to counteract out local short, steep chop on the wide open estuary areas I took the liberty of raising the inwale height at station 2 vertically by 5mm and at station 1 by 10mm.
After having a trial paddle in a friend's Tahe Greenland 'T' to see how narrow Greenland style kayaks handle with 90kg 1853mm paddler on board, I raised the 2 aft deck beams 10mm to make the aft deck a little more water shedding than the standard flat aft deck.

Purchased a 5.8m (19')length of straight, clear, lightweight, Western Red Cedar and cut all the longitudinals (inwales, chines, deck beams, keelson) out of the one piece with sufficient WRC left over to make the cockpit floor boards, foot-braces etc.
The final size of the Western Red Cedar longitudinals, as determined by the rip sawing from one 100mm x 50mm rough sawn plank on a kayaking friend's huge panel saw set-up are :-
Inwales : 36.5mm x 19.5mm
Chines, keel, deck beams : 25mm x 19mm
The frames and stem & stern plates are from 12mm marine plywood; the 'breast hooks' (if such exist on a kayak) are from some 9 mm marine plywood I had on hand. The complete set of 6 frames weighed only 1028 grams.

Communication with an NZ builder of a Sea Rider alerted me to trialling leg fit thru the “masik” at the fore end of the cockpit (he had to raise his masik 3” to accommodate a 'frozen' ankle problem); the upper edge of frame #3 was left uncut as seen in the first pic. There was not enough shin clearance for me so the under edge of the frame was re-cut in a curve (as can be seen in the second pic) but still passing thru the original points and the upper edge of frame #3 was cut in a matching curve maintaining the intended frame depth.

The chines, inwales and keel were epoxy glued and screwed to the frames but when the glue hardened the screws were removed and replaced by glued dowels.
My Tahe friend loaned me his SmartTrack footrests for a guide for installing timbers to suit commercial footrests (conveniently SmartTrack, SeaLect and Yakima all use the same 14.5" longitudinal hole centres) but the commercial sets were too heavy so I made timber 'pegs' matching the same fixing centres.

The SmartTrack footrests (right) weigh 470 gm whilst my timber equivalent (left) with the actual pads much larger than any of the commercial footrests weigh only 146 gm with its first coat of varnish and the timber was all scrap bits for zero cost.

Apart from four S/S screws allowing adjustment of the footrests, there are no fasteners in the kayak.

The most difficult part of the build was the cockpit coaming. "Cut and stacked" plywood was going to be too heavy, extremely wasteful of plywood and expensive however the alternative, steam bendable timbers, are hard to find in Western Australia. Did find a piece of American White Oak as preferred by F1 builders (some used in Aust for flooring) but it was already kiln dried and the grain was not quite straight enough. Finally succeeded with steam bending and laminating “green” Australian Spotted Gum.

The finished frame weighed in at 7kg

Ballistic nylon skin and the associated "Goop", dye, synthetic sinew and floatation bags were imported from Corey's SkinBoats.

There were a couple of small wrinkles in the nylon skin at the aft end of the cockpit but judicious and VERY careful use of a hot air gun successfully removed the wrinkles.

The finished product weighed 11.7kg (under 26 lbs) and is, of course, paddled with a self-made, lightweight GP also carved from WRC.

On Launching Day, the champagne honours went to my wife - pouring a small amount across the bows with the remainder of the champers going to the assembled “launching party”.

It has been a most enjoyable and challenging build. Many thanks to Tom Yost for his marvellous, free design and to Dave Gentry, John Abercrombie, Terry Reed and a number of others for their contributions and encouragement.

Cheers from Martin Bunny,
Mandurah, Western Australia.