Carbon/Cuben Snowshoes

[Steven Evans]

I've been secretly working away at some crazy light snowshoes (CC Snowshoes). Just finished them this week and they turned out pretty nice. I posted a bunch of pics and info on my website but the basics are as follows:

Size: 9" X 32"
Surface area: 288"^2
Weight: 30.4 oz per pair

http://www.suluk46.com/RandD%20-%20RD13%20CC%20Snowshoes.html

[Bob Gross]

I realize that snowshoes are intended for use on snow only. However, where the snow gets thin, rocks are exposed.

How will the carbon fiber frame parts hold up to crunching down onto rocks?

–B.G.–

[JM Addleman]

Sweet website, too!

[Steven Evans]

I should have added that these really won't be used in an environment where there is exposed rock – think nice deep snow. Or maybe rephrase that as one should use caution when using these in rocky environments. That said, I am a firm believer that almost everything on the market is overdesigned so I'll give it a go and see how they work out!

[Bob Gross]

"think nice deep snow"

Coming from Canada, that is easy for you to say.

In California, we have to play "connect the dots."

Maybe a few feet of duct tape would be the work-around for rocky situations.

–B.G.–

[Steven Evans]

How about wrapping them in CCF and then remove it in the evening to double as a sleeping pad. :)

[Philip Delvoie]

Amazing. Looking forward to hearing your report on how they do on snow.

[David Chenault]

Serious bit of enginerding and fabrication there, my hat is well and truly off. Even a touch of color coordination and contrast.

How easily do the feet rotate/flex forward in the bindings?

Our gear philosophies are quite different Steve, but I have tons of respect for the dedication with which you pursue yours.

[Bob Gross]

I've never had snowshoes that didn't have a front "axle" for the crampon to rotate about. It just seemed necessary at the time.

Years ago, I ripped up a knee while cross-country skiing. The surgeon who did the reconstruction told me that I would never ski again. So, I purchased some snowshoes and got prepared for a trip right after I got out of the cast.

Then I discovered it takes more knee strength to snowshoe than it does to cross county ski, so I went back to skiing.

–B.G.–

[Benjamin Moryson]

woah steven

they look very great and interesting.
now I'm waiting for your test report.

where can i get these extra strong cuben????

[Steven Evans]

Thank you David. Your comments are appreciated. I made a few prototypes out of wood before building the real ones. As for the color co-ordination, you gotta look good on the trail! :)

Here's a pic of when I was trying to work out some quirks.

Right now, I've only used them on the grass because we don't have any snow. On the flat and relatively hard grass surface, I notice no difference between these and the Northern Lites, except of course for the weight. I think the reason is that without the snow, the crampon on the NL is not able to rotate forward as it has nowhere to go. Therefore it gives the impression that the crampon does not rotate and it doesn't seem to bother me. My original design had the crampon rotating, but I wanted to protect the carbon frame and came up with the idea to run the tubes through aluminum tubes on the crampon. This transfers alot of the weight through the crampon and not the carbon tubes. The binding still rotates forward, it's just the crampon that doesn't.

I have fun designing and building my stuff and I recognize that it isn't for everyone. Some people will like it and some won't. I usually like it! :)

Bob, I also sometimes think things are necessary, and I think it due to whats on the market. I see something and I think if they're doing it, then it's the way to go. Fight that urge…I like trying things no one else does.

Benjamin, I bought the cuben from Cubic Tech. They had an off cut and I ended up buying a few yards of it.

[Tim Marshall]

Just awesome Steve, awesome!

-Tim

[t.darrah]

Steve,
I would love to see you use the same binding on your ti crampon.

[Joshua Gilbert]

If you need someone to test them out on snow, I know where to find miles of nice, deep, rock free snow. ;-)

(Well, I am serious, but I'm sure you want to be the first one to try them out.)

[Devin Montgomery]

Wicked cool, Steve! Now you just need to swap out the joints (is that pvc?) for some prepreg epoxy resin carbon wrapping. Bake at 350. How long's your oven? :)

But seriously, very very cool.

[Steven Evans]

Thanks Tim.

Thom, I'm on it. I like your idea. I've been struggling with the binding on the TWC's.

Joshua, I'm actually not sure what to do with these now. We have no snow here, and I made a call up to my buddy who is about 2 hours north…no snow there either. I really wanted to be the first guy to give these a go. I had them out yesterday on the lawn beating them up a bit and ended up losing a screw out of the decking…time for some loctite! It's the little things I want to get worked out before I would send these off.

Devin, yeah, it's CPVC elbows. I had originally tried to use carbon fiber elbows but really only found one place that had them and they are not cheap. I then used aluminum but they were huge and heavy, I couldn't find a thin walled one. So I then thought I would make my own but couldn't get a tight enough bend radius on them…the list goes on…then I was walking in the hardware store and came across the ones you see on the shoe now. I bought a couple and took them home to see how easy I could break them. They're tougher then you think. Tough enough that I wanted to give them a try…so now we wait and see.

[Kevin Beeden]

Steve,

How does CPVC behave at low temperatures? When I was playing with ideas for a version of the Krustyledge, I spotted that most PVC water piping is only rated down to 0C, so transferred my allegiance to ABS, which most claim is good down to -40C.

Not that my Krustyledge ever got past the design stage…

[John Nausieda]

CPVC fractures at 0 degrees if it is full of standing water as the ice expands the pipe or fittings. With a hollow pipe as in a drained irrigation system the pipe doesn't fracture. ABS is used for drains-rarely full of standing water. I'd investigate PVC in future projects. It is much cheaper as are the cements and primers. Purple hot primer is best. CPVC costs more as it is rated for potable water. Still, I'd watch out foreither pipe at very low temps. It definitely becomes less flexible. In fact , I've seen plenty of joint failure in winter in Portland when building outside below 45 degrees. Many people use PVC to construct cold frames.You may want to look at their discussions about failure at low temps under wind loads, or snow loads to get an idea of strength.

[Devin Montgomery]

Hi Steve, I was mostly joking about the elbows. You just set the expectation bar so high that I thought I'd throw something really crazy out there. Even though I'm sure they're bonded in place, this modular design might allow for the replacement of one of the spans if it were to break or become overly worn. Is that a possibility?

[Steven Evans]

I'm not sure how the CPVC will take a little abuse when cold. I don't know a whole lot about plastics. I looked for hard numbers, even on the manufacturers website, but didn't come up with anything concrete. And google is a nightmare when you need to get verified data. My understanding is that CPVC (like many plastics) becomes brittle and loses durability when cold. How brittle and how much durability is lost, I do not know. I can replace them with something else if they prove to be an issue. My aluminum elbows weigh roughly 3 grams more and are 9.5 times more expensive. So on a set of snowshoes, I would add ~1.5 oz and about $210 dollars…you see how that CPVC is looking better now ;)

Devin, I saw the happy face :), but I'd really love to go the route you suggested…but alas, these have cost me an arm and a leg already. When I was designing the snowshoes, I knew there was going to be some testing involved and most likely failures. So I made sure everything can be replaced. I can essentially take the entire thing apart, except for the carbon frame because they are bonded. However, if a tube was damaged, you could cut it out and then grind the inside of the elbow back to it's nominal dimension and bond a replacement shaft back in. I was even originally going to bond the toe crampon in place (to the carbon tubes) but figured I wouldn't just in case I needed to use it on an updated version.

[Lawson Kline]

Your Snowshoes Rock…Whats the list price?

[Benjamin Moryson]

With which material are the carbon tubes coated???

[Steven Evans]

No list price. I need to test these babies out and probably make some changes. But without any snow left, I think they'll hang out in the garage for a while :(

Benjamin, the tubes are coated with a spray on clear coat of some sort. Not really a material. When the shafts were being built, I was simply asked if I wanted them coated to protect them from being banged up.

The shafts are smooth from the coating where as my ice tool shafts have ridges where the fiber is wound. I would guess it's a few thousandths of an inch thick and probably won't make a huge difference, but better then nothing.

[Eric Beaudry]

Steve,

Might be able to get away with thin wall stainless steel tubing for the elbows. Not sure on the weight increase but some like .030"-.050" wall stuff should be too heavy at those lengths and certainly tough. Cost is/would probably be better than the aluminum versions (just order straight tube and a bender).

Just a thought.

Eric.

[Steven Evans]

You think like me :) I tried to go the bent tube route. I'd probably go aluminum before I went stainless, just because of the weight increase. There is an issue with the bend radius though. I would need to use a much larger (~2") radius then what you see on the fittings. This would in turn add to the size (and weight) of each fitting. Ideally, two aluminum tubes cut straight on one end and on a 45* angle on the other, welded together, would be great. However, I don't think I can buy them and making them would be a bit pricey. Something like this:

Of course, the fittings on there now haven't failed…yet ;)…and I'm rooting for them!

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