C-Forum

I just finished up my own design for a new slalom C1 and want to share a few videos of it.

https://youtu.be/sbNc5-krqgM - in the gates
https://youtu.be/0ODCMQtNEbk - pivots
https://youtu.be/c-WVF4Xeu5Q - rolling

I really like the way it paddles.

The idea behind the design is that it is a boat for taller, heavier people on higher saddles who don't necessarily have the balance of an elite world class racer. I'm 6'6" tall, weight 195 lbs and sit on a 5" saddle.

I believe that extra width does two things. First, it gives more stability, which allows for fuller more powerful strokes to be taken without constant balance checks. Second, it makes it easier to keep the boat flat when pivoting. I find that because of the extra stability during pivot turns, I don't lose control of edging and stall out the turn as often.

I also made the boat 3.65M long instead of the minimum of 3.5M. I'm hoping the extra length compensates somewhat for the speed lost due to the extra width.

The last thing that is different about this boat is that I built it without making a mold. I carved a plug from styrofoam, wrapped the plug in packing tape, layed up carbon fiber / epoxy directly on the plug, and after the epoxy cured, cut out the cockpit opening and carved out all of the foam. In addition to not having the build a mold, I did not have to do inside seams and the deck is chemically bonded to the hull.

If anyone is interested I have a lot of pictures of the design and building process.

Finally, thanks to several people on this board and especially Chris Soileau of River Elf and Davey Hearn of Sweet Composites who helped me figure out a layout that would work with my unusual building technique.

Matt

And here are two pictures to show the size comparison with a Vajda Lizard XL.

Pépé on the left and lizard on the right.

Looks very nice, and seems to paddle well for your "excessive" height and weight. The newest boats are trending more and more to certain elite athletes, and that's a bad thing for those outside the 75th percentile.

Very nice! The build method sounds very interesting...have pondered doing something along those lines.

Looks awesome Want to make another one??

Very nice, Matt. 2 questions for you:

Did you vacuum-bag this model?

Where is this boat currently located? May be worth being made available if anyone going to the spring armada wants to stop by and try it out.

Very intereting... nicely done! Whats the lay up on it and end weight? What kind of issues did you have during the process that you can enlighen us on?

Looks great. It would be interesting to see how it compares to some of the narrow premier boats out there for speed... Looks pretty fast in the gates and looks like it fits you perfectly.

Seems like the elite racers are all fairly small people - I've always had the same issue being "large boned"

Nice! Definitely hard to find boats for my weight, even older ones!

How did you get the outside smooth or have you decided that a slightly textured surface breaks surface tension and makes the boat faster?

I've just been repairing a polo kayak, I estimate I've added patches up to about 25% of the surface area of the hull and I'm wondering whether I should just leave them or sand them and flow coat them - it will be lighter and faster than the clubs PE boats either way. I have similar concerns for my C1 although most of the repairs on it so far are to the deck and seam, mind you as someone who could do with a Pepe the seam and deck of my boat drag in the water a lot of the time anyway

Thanks for the complements.

I've been paddling it everyday, working on the outfitting, and liking it more and more everyday.

After I paddle it for a while and if I still like it, and if other people are interested, I would consider making a mold, or trying to get someone who really knows how to build boats to make a mold.

I did not vacuum bag this boat. I don't think the foam plug would hold up to it. The stern was especially thin. We just squeegeed out as much epoxy as possible by hand as we layed it up.

I live in Salida Colorado and thats where the boat is located now. It will be on the Grand Canyon for the next three weeks as I leave for that trip on tuesday. This trip is my reason for getting it done quickly. Anyone coming thru here who wants to give it a go is welcome.

For the initial layup, it is 5 layers of carbon for the hull and 5 layers of carbon for the deck. These were both done before either completely cured, so they are chemically bonded together. There is overlap of the hull and deck on the sides, so up to 10 layers of carbon there. After the initial layup, the area under the pedestal was not stiff enough, so on the inside of the boat, I washed, sanded, and then layup two more layers over a lattice of 1/8" thick foam. This really stiffened up the bottom. With the pillars in, the entire boat is very stiff. As good a Vajda boat.

For weight, after the initial layout, it weighed 17.5 lbs. Then I painted on two layers of epoxy on the outside of the deck and hull to fill in the fabric texture, added two layers of carbon under the pedestal, added the cockpit combing, added 2" foam pillars, strap anchors, and added my custom kneecups/pedestal and the weight is 28 lbs. This is the fully outfitted weight. I haven't finished sanding the outside, so I may sand off a pound or two. This is about 5 lbs heavier than my Lizard fully outfitted. I think this is ok, since this is a big boat, layed up without vacuum bagging by a few guys who don't really know what they are doing.

I'll attach a few pictures showing the issues I had building this boat.

Here is a video of me paddling my lizard in the same place at about the same water this summer. I took the outfitting out of the lizard to put in the pépé, so I can't go out and paddle them back to back. I do feel faster in my new boat.

https://youtu.be/tp_deaX5HgM - Lizard in gates


I am in the process of making the outside smooth. I painted on two layers of epoxy to fill in the fabric texture which was quite prominent. Then I sand it down with progressively finer sand paper. Then I gave it two coats of Krylon clear acrylic spray paint. I ran out of time to do a really good job of sanding, but it looks ok now. When I get back, I plan to sand off the clear coat and make it look really good. I may have to go through a few cycle of spraying and sanding as I got some pin holes when I painted on the epoxy.

One other thing, it surfs really nicely.

https://youtu.be/GNk4O7nG5g8 - surfing

Let me know if I missed any questions.

Matt

For the foam plug, I decided to use white construction foam that is 2 1/8" thick and comes in 4 x 8 sheets. It took 3 sheets total. To build up the plug, I cut out profiles of the boat and glued them together. For the profiles I used some existing boats for reference. I have access to a Loco, Makao, Lizard, and a Wind C2. To take the lines for these boats, I made a chain girth device by pop riveting together a bunch of little pieces of pegboard. There is just enough friction that it can be made to follow contours but still hold its shape if handled carefully. There is one extra small link that I used for the very sharp edges of the stern. This device is simply wrapped around the boat and then the contour is transferred to a poster board. On the boat being measured, I marked out every 2 1/8" and a center line on the hull and deck. I also set up a string a few inches off the deck to take offsets for each profile. The clothes pins are used to mark the center line of the the deck and hull for each profile. I put all the profiles for the hull on one poster board and all the profiles for the deck on another one. You can kind of see the shape of the boat from these lines.

This is the bow.

This is the stern.

Next I modified the profiles as I thought best. Then I cut out thin plywood templates for every 8 1/2" of length of the boat. I would then use the two templates for each 8 1/2" section to cutout four layers of foam with a hot wire cutter. I glued all these profiles together and shaped and sanded the plug smooth.

Here is the plug after some shaping. You can see the 8 1/2" sections here.

After more shaping and sanding and cutting in the cockpit recess with a router.

After I was happy with the shape, I covered the whole thing in clear packing tape. There is no need to worry about texture or small pits in the foam plug. Between the packing tape and layers of carbon, that all disappeared. I made sure there were no wrinkles in the tape where epoxy could grab hold.