width of wood core strips: 19 mm
epoxy: West Systems with 105 resin with 205 hardener
vacuum pressure: -11 psi
duration of pressing: 10 hours with the addition of a heated
blanket purchased from Target
Graphics - color was achieved using fabric; text and logo were printed on
card stock, then cut and placed beneath topsheet during the layup process
Builder - Big Kam
Date Manufactured - December 16, 2006
Comments and Test Report (by Big Kam)
Skip started shouting "grande cocoa!" at the top of Hidden Lake Peak on April
4, 2004 (click to see movie).
(A group of friends and I were out for a ski tour in the North
Cascades.) What got him started was earlier that morning Cass (pictured
above) had ordered his favorite hot beverage at the local espresso stand by
asking, "I'd like a grande cocoa please." (Cass does not drink coffee.)
Since that day, when we greet Cass, or when we want to get his attention, we holler "grande
cocoa!" (or other things, but I won't mention them here.)
Obviously, the name Grande Kokoa was inspired by Cass. Cass is a very close
friend, and I've shared countless days with him in the mountains, climbing,
skiing, and biking. For example, in July 2004 I easily persuaded him to carry skis,
gear, and food for a three-day adventure into the heart of the North Cascades to
climb and ski the remote Mt. Spickard. The approach was BRUTAL: 6 miles of bushwhacking, then climbing up a gigantic waterfall named the "Unforgettable
Waterfall", followed by a few miles of scrambling over boulders and loose choss.
And that was just to get to camp! Oh, did I mention stepping on fresh bear
scat? Here, watch the video of
the bushwhack (5MB, *.asf), and below are a few photos of Cass from the
Cass likes short -- I mean short! -- skis. Also, he's partial to them
being somewhat stiff. The Kokoas are just right for him: short and stiff.
For the core, I settled on a mix of poplar and Douglas fir (Elastic Modulus of 8
to 12GPa; cf. Maple 7 to 12 GPa):
This was my first time using fir, and it's a relatively light and stiff wood.
In the above photo, the way I laminated the core produced fir sidewalls.
With an 11.5mm thick core underfoot, they were definitely stiff...
I designed the Kokoas with a somewhat relaxed shape -- 126 mm at the shovel, 111
mm at the waist, and finally a modest 115 mm wide tail.
Absent are fancy materials -- just wood, epoxy, and fiberglass
(and of course edges, base material, fabric, and topsheet). Besides, Cass
prefers plain salads, no special sauces or spreads on his chicken sandwiches,
and cheese pizzas.
I have been using Little Kam's press and the one Kelvin and I built to make
skis. I don't have a pneumatic press in my garage, but recently I got a
hold of a vacuum press to test. This is the first time I've used a vacuum
press, and it's not a bad way to build skis. For me, the thought of
"sucking" materials together is less threatening than blowing up a fire hose.
I have to admit, pneumatic presses are intimidating contraptions, not to mention
they can hurt. But I am building a pneumatic press, so stay tuned!
The vacuum press that I used was built from a kit, purchased from
JoeWoodworker.com. The system uses an air compressor, something I own.
I used a 0.040" thick vinyl sheet and lot of duct tape to form the "vacuum
chamber". I was too lazy to look for vacuum-pressing tape, so gave duct
tape a try. Duct tape seems to work, but it's still a challenge to get a good
seal. In the photo below, it looks like I went overboard with the tape,
but there were still small leaks. My compressor came on every 5-10 minutes
to keep up with the loss in vacuum pressure. I managed to pull down to -11
psi, and it was enough to squeeze all the materials together. I vacuumed
for 10 hours and I covered the skis with a heated blanket purchased from Target.
The graphics of the skis were simple: thin colored cloth below the topsheet, and
the logo and text were cut from card stock. Here's what the skis looked
like immediately after pulling them out of the vacuum press.
A close up of the wood sidewalls and edges after beveling with a router:
After I finished the Kokoas, I flew to So. Cal. to visit family for the holidays
and to spend some time with my cousin Little Kam. Interestingly, Little
Kam also created a new ski: the Boondoggle Pro. Unfortunately, due to lack
of snow (and motivation) I did not test the Kokoas with Little Kam in So. Cal.
Instead, I went to Seattle. (I had to ski before the end of the month to keep my
Turns-All-Year streak alive!)
My flight landed at 1:30am Sunday (Dec. 31st) morning because of a delay. I
to drive 5-6 hours from Seattle to the Methow Valley to join Cass for a tour on Sunday morning.
But for some
reason the thought of whiteknuckle-driving over the pass and potentially snow-covered
roads early in the morning seemed like a bad idea. Instead, I reconfigured my plans then
arrived at Kelvin's house at 5:50am to find him warming up his garage with a propane heater
and powering up the wet belt sander. In ten minutes we cleaned up two pairs of skis
I brought -- the Grande Kokoas and the Bangers and Mash. I was excited to test
We decided on Jim Hill Mountain after Kelvin pointed out the temperature was colder around the passes.
We ascended via a snow-covered access road with a nice uptrack.
Kelvin ascending a snow-covered access road. Stevens Pass
in the background.
it didn't last long after I decided to travel up my "favorite" route: the kind of route that you
use to sneak up on a mountain. The snow felt nice and consolidated, about 6-12 inches above a
firm base. We took turns breaking trail through the woods and navigating.
"Remind me again why we're traveling this route..." Skier:
I thought it was a
great route and have traveled to Jim this way about five times. Besides, I needed the (schwacking)
exercise. Anway, we slowly made our way up the woods, chit-chatting like a couple school kids.
conversation was mostly about making skis and the meaning of life.
Around 1:30pm we decided to ski down.
The snow in the woods was nice, and light in some places. As for the Kokoas, I enjoyed the turning
radius, width, and length. But it was a bit stiff for my taste. I can
picture shaving 1-2mm from the core thickness to give them a "softer" flex for
Kelvin skiing the Bitchin' Camaros through the woods below Jim
After personally testing the Kokoas, I handed them over to Cass. The
following Wednesday, we night skied at Snoqualmie Pass. Cass jumped on the
skis and immediately fell in love. In fact, there was a free telemark demo
that night and he skied the Kokoas against several mass-produceds and found that
the Kokoas skied better than most. I took a couple runs on the hardpack
and found they carved nicely, too. Being stiff, they gripped the snow with
little effort. I compared the mass-produceds with my Bangers. I
enjoyed one or two mass-produceds, but overall homemade skis carve as well and
even better in some cases -- I won't mention any brands or models...
[Check out the video of Cass on the Kokoas
Several days later 10-15 inches of new fell in the mountains. We skied
Crystal Mountain resort and found tons of powder. I skied the Bangers with
new BD 01 bindings. (Great binding by the way.) Cass cruised on the
Kokoas and loved them in the powder. Grande Kokoa!