Monthly Archives: October 2016

Seat development

I’ve now got quite a collection of racing kayak seats in my quest for a better canoe seat design. One thing that has struck me is that they are all pretty much the same size and shape. OK there are a few tiny differences but the manufacturers seem to assume that one size will fit all racing kayak paddler’s bottoms.

Once again, compare this to the cycling world where there are literally hundreds of saddle designs, shapes, sizes and materials, plus a whole host of different options for lady riders.

The discerning canoe racer however is more demanding, and much prefer a tractor seat type design, plus they are seated much higher.

Anyway, I set about modifying my original effort and recast it to have more volume at the back.

Increased surface area

Increased surface area


The picture shows the size compared with a “standard” racing K1 seat.

Next I needed something on which to mount it. I have made a number of seat supports using timber and fibre glass, but they take so long to shape them to support the seat pan.

As it happened, two new seats from Nelo had just arrived. These are a rather different and innovative design in that the seat is supported by a cast metal frame.

Nelo K1 racing seat

Nelo K1 racing seat


The seat pan is secured by five rivets. So I drilled off the rivets and separated the cast metal “spider”.

Nelo seat "spider" support

Nelo seat “spider” support


Together with some stainless steel bolts and some plastic spacers, I secured the new seat pan to the frame.

New seat pan secured

New seat pan secured


I had just got the Darkness Duet back for a few days, so I bolted it into the rear of the C2, and John and I took it out from Pewsey Wharf.

New seat in rear of Duet

New seat in rear of Duet


I’m showing it compared with a K1 racing seat. The marks around the edges are where I used pegs to hold the two layers of foam whilst the glue set. At this point I was reluctant to cut the seat runners down.

Well at first it felt weird because it was different to what I was used to. On the return from Wootton Rivers I’d forgotten about the new seat and was quite used to it after the hour.

I’ve now made a second one and secured both to square profile aluminium tubes ready for testing. I’ve also trimmed the runners.

New seats ready for testing

New seats ready for testing


I’ve mounted them on timber supports so they should sit on the flanges with just the timber drilled to math existing holes.

I now need to get them tested.

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Does my bum look big on this?

So, just got back from an hour’s paddle on the Basingstoke canal using the wider seat. It was unexpectedly uncomfortable!

Having more bum area in contact with the seat actually felt more stable, especially in combination with the pull bar. Also having more area at the back of the seat enabled me to push back into it. But the pressure points seemed to be in the wrong place.

One factor compared with a C2 setup, is that the height of the seat is significantly lower in a C1 than a C2. In the C2 I have set the seat height to 20 cms, where as in the C1 it’s set at 12 cms. This may make quite a difference, which I can test once I get my boat back.

Those of a nervous disposition may wish to look away now, but I’ve taken some photographs to illustrate the point.

The first picture shows a standard British bottom on a standard K1 racing seat. Neither the back nor the sides are supported. However, this may be because there is so much movement due to the paddling action.

Standard K1 racing seat.

Standard K1 racing seat.

I wonder if it’s the same principle as in cycling, whereas novice cyclists are often convinced that their sore bums would benefit from a big, wide saddle, where in fact all racing cyclists tend to use narrow saddles which support the bits which matter most.

So-called cycling comfort saddle versus cycle racing saddle.

So-called cycling comfort saddle versus cycle racing saddle.


Now compare the area of support with my new wide seat design. Much more bum area is supported.
New wide seat design.

New wide seat design.


I do wonder whether the seat would benefit from sides in the same way as sports car seats are designed.

Yes I know they have sides to prevent slipping out of the seat due to the G-forces during turning, but are they more comfortable?

The seat I use at the moment is a bit of a compromise in that it doesn’t have hard edges and allows the “excess baggage” to overflow.

Current C1 seat.

Current C1 seat.


For DW, John and I used Zastera seats with two layers of foam. They seemed comfortable to us, even on the long pound to Wootton Rivers, but it’s the additional height which seems to make the most difference
Darkness Duet DW seats.

Darkness Duet DW seats.


I need to get some wide seat prototypes out to the Duet paddlers.

Bums on seats

One of my original design goals, and indeed a unique-selling-point of The Darkness, was the ability to use the seat design most suited to the paddler. This was delivered using a simple flat platform mounted on flanges on the inside of the boat. On this, I mounted a foam seat which was larger than the usual kayak racing seat, and theoretically much more comfortable over longer distances. If necessary, it could be changed quickly during a race as conditions dictated, for example a lower seat for more stability.

Unfortunately I wasn’t able to find someone who could make the foam insert in a single lump, and had to construct the shape from multi layers of foam matting. It worked, but didn’t look great.

Original seat concept.

Original seat concept.


At some time or other, I decided to use a kayak seat after all. I can’t remember when this was, but I experimented with a number of different designs.
Carbon seat fitted

Carbon seat fitted


I didn’t think any more about it and proceeded to use carbon kayak seats on the Duet.
As I was able to persuade a few people to start testing the Duet, one of the main subjects of feedback was how uncomfortable the seats were compared with the traditional tractor seat design used by Wenonah. So I set about designing a bigger seat.

I am somewhat restricted by the availability of tools, materials, experience and skill. I have good ideas, but translating them into something tangible doesn’t always work out in the way that I’d imagined it. So instead of starting from scratch, I used a K2 seat I had as a platform. I taped on an end-stop and filled the gaps with expanding foam. I didn’t realise quite how much this stuff expands!

K2 seat with expanding foam.

K2 seat with expanding foam.


Anyway as soon as it set, I cut it down with a saw.
Foam cut down tp shape.

Foam cut down tp shape.


And then applied some filler.
Filler applied and smoothed.

Filler applied and smoothed.


My plan was to use the shape to make a mold. I would then use the mold for testing and then to produce more seats. Unfortunately I didn’t have any chopped-strand-mat fibreglass which is best for making molds and had to use carbon fibre instead.

Carbon fibre isn’t as malleable as fibreglass. Plus I used too much resin. Anyway, I wetted out 4 layers of 200 grams carbon, covered it with peel-ply and cling film and popped it into one of those vacuum bags used for compressing clothing during packing.

Seat under vacuum.

Seat under vacuum.


I used this technique when I was making paddles and it’s quite effective (and cheap). Once it had gone off, I stripped off all the peel-ply and cut it to shape with my dremel.
Seat size comparisom.

Seat size comparisom.


Compared with the kayak seat, it is about 4 cms wider.
I then made a seat support, the same dimensions as the kayak seat so that it would be easily changeable in my existing boats, plus it could be used in a conventional racing kayak.
Seat with support and fixed to platform.

Seat with support and fixed to platform.


I mounted it on a plywood platform so I could fit it to my C1 for testing, and stuck on some cushioning.
Seat fitted with foam cushioning.

Seat fitted with foam cushioning.


I’m on the water tomorrow to see how it performs.