I used a core I profiled shortly after finishing my first pair, but never got around to using. I patched together some scraps of base material into nifty die cut bases, and routed using a new and much simpler jig.
I used Resin Reseach Project 21 2000 resin and their slow hardener, giving a pot life of 50minutes and a cure time of 5 hours at room temperature.
The design is something like the Line Chronics, 170-some cm long and dimensions around 120-90-118. There is some camber underfoot as well as tip and tail rocker.
Layup went smoothly on the first ski, but took nearly an hour even with the help of my dad.
This time I wanted to heat the ski while pressing, because everything I've read suggests that a heated cure not only gives faster bonding but also much stronger bonding. Heating blankets are most commonly used for this, but they're expensive and difficult to find. I came up with a simple hot box and decided to try it, despite finding few examples of this technique online.
With layup complete and the press inflated I slid over a box of 1" foam board insulation, sealed up the ends, and placed two small space heaters blowing into the box.
I pressed for four hours like this. During that time my firehose blistered and popped near the end (thankfully only damaging the outer protective layer and not the inner structural layers). Temperature in the cat track reached 105F, and temperatures in the top of the box neared 200F. After four hours I pulled out the skis, thinking with the heat inside they should be done early. The epoxy was far from cured, which was quite disheartening. I put the press back together and pressed for another two hours, for a total of six hours. After which, the epoxy was cured and the skis were looking quite good.
Tomorrow the second ski gets pressed and they both receive a high temperature post cure.
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