Martin B.
22nd July 2013, 05:49 PM
Hi all,
The build story 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 Y. was most helpful with advice on craft selection to suit my local paddling conditions o a 137 sq km estuary and associated minor rivers (2) plus allow for my aged and somewhat damaged carcase. I read and re-read Yostwerks on-line info and followed the Internet Manual fairly closely.
277945
However I attached all 6 frames to the strongback to guarantee the design rocker was achieved and to ensure that the keelson was straight. 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 friends Tahe Greenland 'T' to see how narrow Greenland style kayaks handle with 90+kg paddler on board, I raised the aft deck beams 10mm to make the aft deck a little more water shedding than the standard flat aft deck.
277946
That's the Prijon Touryak hanging above the SoF frame in the garage.
Purchased a 5.8m (19')long 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 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.
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.
277947
The weight of the SmartTrack footrests (right) was 470 gm whilst the weight of my timber equivalent (left) is only 146 gm with its first coat of varnish and the timber was all scrap bits for zero cost; lightening holes were sawn in the ply pads before final varnishing.
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 (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
277950
Ballistic nylon skin and the associated "Goop", dye, synthetic sinew and floatation bags were imported from Corey's SkinBoats, USA.
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.
277956
The finished product weighed 11.7kg (under 26 lbs) and is, of course, paddled with a self-made, lightweight GP also carved from WRC.
277951
On Launching Day, the champagne honours went to my wife - pouring a small amount across the bows with the remainder going to the assembled “launching party”.
277953
It has been a most enjoyable and challenging build; the craft carves thru the water with absolutely no fuss and minimal wake disturbance. Many thanks to Tom Yost for his marvellous, free design.
(Happy to answer any queries on the build within my particular sphere of [un]expertise !)
Cheers,
Martin B.
Mandurah, Western Australia
[email protected]
The build story 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 Y. was most helpful with advice on craft selection to suit my local paddling conditions o a 137 sq km estuary and associated minor rivers (2) plus allow for my aged and somewhat damaged carcase. I read and re-read Yostwerks on-line info and followed the Internet Manual fairly closely.
277945
However I attached all 6 frames to the strongback to guarantee the design rocker was achieved and to ensure that the keelson was straight. 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 friends Tahe Greenland 'T' to see how narrow Greenland style kayaks handle with 90+kg paddler on board, I raised the aft deck beams 10mm to make the aft deck a little more water shedding than the standard flat aft deck.
277946
That's the Prijon Touryak hanging above the SoF frame in the garage.
Purchased a 5.8m (19')long 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 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.
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.
277947
The weight of the SmartTrack footrests (right) was 470 gm whilst the weight of my timber equivalent (left) is only 146 gm with its first coat of varnish and the timber was all scrap bits for zero cost; lightening holes were sawn in the ply pads before final varnishing.
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 (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
277950
Ballistic nylon skin and the associated "Goop", dye, synthetic sinew and floatation bags were imported from Corey's SkinBoats, USA.
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.
277956
The finished product weighed 11.7kg (under 26 lbs) and is, of course, paddled with a self-made, lightweight GP also carved from WRC.
277951
On Launching Day, the champagne honours went to my wife - pouring a small amount across the bows with the remainder going to the assembled “launching party”.
277953
It has been a most enjoyable and challenging build; the craft carves thru the water with absolutely no fuss and minimal wake disturbance. Many thanks to Tom Yost for his marvellous, free design.
(Happy to answer any queries on the build within my particular sphere of [un]expertise !)
Cheers,
Martin B.
Mandurah, Western Australia
[email protected]