Virgin Voyage / Materials test

So, did they work, and how were they? Show everyone proof that your ride was a success (or even a complete failure)!

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Bucky Mullet
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Joined: Mon Oct 09, 2006 5:26 pm

Virgin Voyage / Materials test

Post by Bucky Mullet »

So, after a long learning curve I mounted up my DX's (186's, 96mm underfoot 21m radius). They were quite flexible, something that worried me at first, but I figure I'd stick to groomers and keep them from folding. The test run was at Taos Ski Valley, and I was immediately blown away. At first I thought that I had mounted them too far forward (1" behind the running edge center) but due to the soft tails, this was perfect (I was actually shooting for stiff boards, but hey, I'll learn). These babies tracked like a race ski, and although I could see the tip vibrating, they held great when thrown sideways.
The core was a symmetrical vertical laminate of thin Hickory strips (as center stringer and one outer stringer on each side) and Aspen. While I had been steered away from aspen due to it's rupture modulous, I liked the fact that you can get 8' lumber where the grain runs the entire way, reducing one of the biggest core fail points- grain termination. I layed up the first ski entirely with material from snowboard materials.com, but then ran out and bought some of the Vectorply from skibuilders and got samples of PTM&W PT2050 A/B1 resin system. The skis were pressed with a vacuum press on a homebuilt mold, using a vacuum pump (bought on ebay for ~$80.00) that is capable of pulling down to below 50 mTorr, essentially reaching the entire 14psi available via vacuum. I liked this idea because the epoxy will infiltrate everything (hopefully) under vacuum, and this might help Kam's foam ski construction. Next pair I would like to combine vacuum with a hydraulic (firehose type) press in order to get the best of both worlds.
Now for the post-mortem. During a few spins through the terrain park, the front of the outside (?!) edge of the ski built with the snowboardmaterials resin system pulled. After a quick duct tape fix as to keep the ski repairable, I hiked up to the West Basin and skied Fabian / Stauffy spine, a technical line requiring tome drops etc.. and a bumpy runout. After three of these types of runs, the skis were still ripping the groomers, and sailed beautifully over my favorite rope huck. However, when I brough them to my buddies in the shop to brag and check them out, it turns out that the initially damaged ski actually had suffered from some delamination behind the tip.
I hesitate to say that this was due to the epoxy system or fiberglass received, or whether I simply didn't apply enough material in those areas. I will however stick with the Vectorly and PTM&W system from now on (thanks for the fabric guys). The damaged ski is being repaired, and if it tholds up for another 2 weeks they'll see action in the Taos extreeme comp.
I'm hooked, from now on I'm a ski builder. These things were awesome. Thanks to everyone who answered questions, pointed me towards supplies and put in the enormous time to put together this site.
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bigKam
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Post by bigKam »

Bucky Mullet: glad to hear they skied well! tip/tail delam is common. ways to avoid it is to properly clean all the materials, especially the edges, prior to layup. also, the edges should be either sandblasted or abraided with sandpaper. pre-bending the base material with attached edges can help minimize stress that leads to delamination. having the right epoxy is a definite plus, and if you can, elevate the temperature during layup to help the epoxy cure.

congrats on your first! good luck on the comp!
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