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Dimensions

  • tip-waist-tail: 90-91-90 mm
  • length: 173cm
  • sidecut: inside edge - 4mm standard, outside edge - 4mm reverse
  • tail-tip type: twin-tip

Materials (top-to-bottom) clear P-tex topsheet, flannel with hand-painted graphics, triaxial fiber glass (22 oz.), core (birch and poplar) and UHMWPE tip and tail spacers, triaxial braided fiberglass (2-layers), clear base material and edges.

Misc info

  • epoxy: QCM; resin: EMV-0049; hardener: ECA - 315 (15 minute set); 5 to 1 mixing ratio
  • pressing time: ~11 hours
  • weight: n/a
  • inserts: steel 1/4-20 thread inserts configured in G3-binding pattern
  • date manufactured: July 28, 2005

Ski Builders: Kam K. Leang and Kam S. Leang

General Comments written by Big Kam (Kam K. Leang)

Why Kanana?  Because it reminds us of a banana -- the shape, that is.  As with every ski, there's a story.  If you're impatient and want to know why without having to read on, the skis got their shape by accident.  Yes, by accident.  And there's nothing wrong with accidents, you know. The transistor was invented by accident.  Sticky Notes by 3M were also by accident.  An apple fell on Newton's head, by accident...  Anyway, the shape naturally conjured up the thought of a 'banana',...so we have Kanana.  Originally though, I wanted to build a ski with no shape, just zero sidecut.  But to our surprise the base material warped after we cut it.  Instead of throwing out yet another pair of good base material, Little Kam and I decided to just lay them up.  Coincidently, other SkiBuilders were also experiencing the warping base behavior at the same time that Little Kam and I noticed the phenomenon.  The topic is discussed in the forum (click here to join the discussion).

The cause of the warping behavior isn't clear yet, or at least it's not clear to me.  We speculate that we got a bad batch of p-tex.  If anybody knows more, please share.

Over the month of July I went down to So. Cal. to visit my family.  I spent some time with Little Kam.  Every time my cousin and I are together, we talk about skiing or building skis.  At first we got our skiing fix by going to San Gorgonio Mountain and Jepson Peak (see the trip report that Little Kam wrote).  Then to satisfy our ski building appetite, we built the Kananas in Little Kam's shop in Riverside, CA.   The motivation was I wanted to try out his new press and share some ideas with him about design.  Kam has been busy making skis and he had a couple new techniques up his sleeves that I wanted to investigate.

So at first I designed a zero sidecut ski that was approximately 125mm underfoot.  The skis were 178cm in length.  We drew up the design, then cut out the paper template.  Before cutting out the base material, Kam and I glued up the cores.  I decided on a mix of birch and poplar.  My goal was to build a more backcountry friendly ski, i.e., something that was reasonably lightweight, and perhaps narrow.  Poplar is nice and light.  After the glue dried, we attached UHMWPE material to create sidewalls.  Then we profiled the core using Little Kam's planer.  For the first time I saw Kam's new profile jig for profiling with the planer.  This technique is described on this site.  Kam's method is different than the way Kelvin and I profile our cores -- we use a router.  Anyway, after we profiled the core, the next steps were to cut the base material, bend the edges, make the graphics, and finally press.

Our progress came to a hault after cutting out the base material and gluing on the edges.  At this point we noticed something strange.  The shape of the bases were warped, including the edges.  Strange.  At first we thought it was the template shifting during the cutting process.  So we cut out another pair of bases and glued edges to them.  And again the bases were warped.  The bases warped from zero sidecut to a design with sidecut on one side and inverse sidecut on the other.  It looked like a banana, hence the name Kanana.  The warping was rather significant.  We measured up to 10mm of deformation over the 178cm length!  Puzzled by the behavior, we started to investigate the cause.

We did not find any evidence that the warping was dependent upon the method used to cut the base material.  For instance, using scissors, utility knife or router didn't make a difference.  One interesting observation was the warping occurred within minutes after we cut the base material.  This observation lead us to think that perhaps there were internal stresses that, after we cut, caused the material to take on another -- more stable -- shape.  The other cause could be related to temperature.  It was rather hot in So. Cal. in July.  But temperature being the cause didn't seem to make sense considering there wasn't much of a gradient.  Kelvin found information that claimed the p-tex had a very high coefficient of thermal expansion.  That could explain it, but during the time of warping, there wasn't much of a temperature gradient.  The garage temperature more or less remained constant, ~90 degrees.

At the same time that Little Kam and I discovered the warping, a post appeared on SkiBuilders' forum discussing the same subject (click to see the forum).  What a coincident!  Surprised, I we continued to investigate.  Interestingly enough, they were also working in a hot environment.  We didn't really come to a definite conclusion about the cause of the warping though.  Maybe they got a hold of a bad batch of p-tex too.  Hmph.

Little Kam purchased his p-tex from Durasurf.  I called Durasurf and spoke with someone who I thought was an engineer.  He pretty much told me that it could have been a bad batch.  Furthemore, he told me that the effect, also known as "cambering", was rare, but it occasionally pops up and is usually associated with a mistake in the manufacturing process.  Whether I believe that or not, there wasn't much I could do.

So I decided to lay up the warped base material.  Being that homemade skis is an experimental process (and of course we're trying to have fun), we welcomed the Kananas as an addition to our quiver of prototypes.  It's definitely an odd design, where one side has sidecut and the other has inverse sidecut.

Anyway, below is a close up of one ski, showing the inserts and the sidewall.  For durability, the inside edge sports a UHMWPE sidewall.  The outside edge has birch sidewalls.

The graphics were simple.  We used cloth and painted over it with cloth paint - nothing fancy.  The QCM epoxy was new to us.  We used the fast 15-minute setting version, and it was fast!  If you decide on this type, then work fast.  We laid up one ski at a time and when working in a garage where the temperature was >80 degrees, there was little time to spare before the epoxy set.  We managed, but a bit slower setting time would be nice.

Overall, the Kananas turned out pretty nice.  The final design has a narrow shape, roughly 91mm underfoot.  The original design was 125mm, but that would have been a bit much for a backcountry ski, especially on steeper terrain.  I toned it down quite a bit, and I'm satisfied with the profile 90-91-90mm.

Test Reports (by Kam K. Leang)

July 30, 2005, Columbia Glacier
Soon after the Kananas came out of the press (cure time: 2-days), I took them back up to Seattle for a test drive.  The day after I arrived in Seattle, my friends Chris Cass and Skip Swenson and I went to look for some skiing in the Monte Cristo area.  If you're not familiar with this place, I've written a few words about it here.

Instead of coming at it from the north, we decided to approach from the south.  Our goal was to find snow on the Columbia Glacier, just below Columbia Peak, a neighbor of Monte Cristo Peak.  Our thought was the approach from the south would be fun, requiring some additional gear, e.g.,

We split the weight of the raft by carrying different pieces.  In the end it was worth the hassle because to get at the glacier, it was much easier to paddle across the 3/4-mile lake instead of trying to find a way around the edge of the lake, which was pretty much steep and overgrown terrain.

After hours spent on the approach, we finally stepped on the glacier.  There wasn't much left, mostly neve and water channeling through runnels.  I'd never seen so many runnels.  There were rocks everywhere, but that didn't seem to deter us.  (Keep in mind that we're not typical skiers...at best, think of us as Patch Skiers.) We managed to find some skiing, and below is a photo that Skip shot of me making turns for the first time on the Kananas.  They were pretty fun to ski... think of something with a split personality!

I enjoyed them very much, and they seemed to handle pretty well.  I was surprised to find how predictable they were.  At first I was expecting them to take me for a ride because of hybrid sidecut design, but they remained in control.  I liked feeling the regular sidecut on the inside edge -- felt comfortable on harder snow.  The inverse sidecut on the outside edge was noticable -- they turned at the slightest pressure.  The narrow design was nice, too, especially on harder conditions.  Again, the snow was far from perfect.  We found a nice section of corn, but everything else on the glacier was pretty much like this:


Skip demonstrates the mandatory technique of a jump turn that patch-skiers utilize frequently.

We skied to where the snow stopped....literally!

August 02, 2005, Paradise Glacier, Mt. Rainier
A few days after the Columbia Glacier adventure, I got a hold of Greg Louie and we went to look for some skiing around the Paradise Glacier, on Mount Rainier.  The first thing we found was this neat little patch that Greg had his way with...

After that, we got a little more serious and found some decent skiing near the lower Paradise Glacier.  We yo-yo'ed a bit and I got to test again the Kananas.  And they were great!  I pushed them a little harder and was surprised to find that they carved nicely.  The one thing I noticed about them was they required me to stay well balanced.  I think the reverse sidecut demands a little more attention than traditional sidecut skis, which isn't a surprise, especially on harder snow.  Anyway, here are a couple more photos: first one is of Greg with Mt. Rainier in the background and the second one is of me carving on the Kananas (photo by Greg, of course).


Greg getting busy.  Mt. Rainier in the background.  Not bad for August.


Me on the Kananas.

Is there a future for this design?  Of course.  There's a future for all sorts of other designs too.  Variety is the spice of life....

 

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