This time it's all about carbon. We'll try an see if we can make it work, to get light and fun powder skis for our trip to Japan in January/Feb 2013.
We have no idea really what we are doing but that makes it more fun
Today we planed some cores and we'll be building both superfat powderskis, lighter touring skis, powder snowboard and 2 splitboards.
Anything and everything can go wrong but with beer and friends we'll give it our best.
My two pair of skis (cores) are in pictured below. The idea is to use triaxial carbon fiber and maybe even plain aramid on top.
The cores are mainly poplar, with some other wood mixed in. Most of our sidewalls will be bambu and the rest plastic..
I second what OAC said about working with CF. Make sure the pot life of your epoxy/resin can handle an extra 10-15% wet out time. I generally pour out an extra helping for my CF layers, and wait for it to soak in. I look for a little pooling on top before moving on to my next layer.
Better to have the extra press out than not have enough inside...
Thanks for those tips guys. I'll make sure the CF is wet out completly. Is there any difference in preassure recomended when pressing?
Since there is more epoxy,
is there risk that too much preassure can press out to much epoxy and leave the fibers too dry?
The pressing is still weeks away but the work is movin along
This time with CNC'd bases, I hope that will increase the final results alot!
As pressing is a few weeks away, you still have time to think this one over and you sound like you want to take the considered approach, so here goes.
If you assume the mechanical properties of the ski/laminate will be derived from the mechanical properties of the fabric and in small part the resin, then you will need to consider a number of factors.
1. What is the optimal resin ratio for each fabric you will be using .. you might need to compromise if you are mixing fabrics
2. What might you reasonably obtain when laying up by hand
3. How much will be lost to the sheet below the fibre when you wet it out and empty the mixing cups (you can always weigh them afterwards)
4. How much should you allow in your calculations for penetration of the core - you may decide coat the core in advance or process these separately.
If you find a good resin ratio calculator (online) and keep track of your numbers, then you will know what you have achieved. Be a bit cautious around the tips - wasting a few grams here is OK.
The press serves a number of purposes, but the aim isn't to press out as much as possible .... that's money down the drain and dangerous if not treated with caution. You want enough pressure to ensure good amalgamation, avoid void formation due to negative pressure and achieve good tip compliance.
Keep asked questions dude, its the only way to divine your own route through the maze!
Ok so the project is slowly moving forward, we are currently waiting for our cnc'd template so that we can process our bases perfectly.
In the meantime we are preparing our cores and making new molds. I really hate putting together those split papers from snocad-x.
Next time I'm buying a largeformat printer for sure.
Does anybody still do this by hand or is it just us? Anyhow, bamboo sidewalls are glued on and the boards are planed to perfection
This weekend is entirely dedicated to building since my gf is visiting a friend = skibuilding time!
And don't worry, I think most people still do most of this stuff by hand, you're not alone.
I bought a large format printer a few years ago for plotting out templates, but now that I have my CNC I'm realizing I have zero use for the plotter... need to try and sell it now. If only we weren't half a world away!
First pair is in the press and tomorrow I'm excited to open it open it up to see the results. This is the first pair of skis with carbon so I have no idea howit will turn out. But maaaaaaan carbon fiber is sexy
4 more pairs to go before heading of to japan for 6 weeks of powder testriding with over 400cm of snowfall so far this season our skis and boards will be in the right environment
Hey Sonny.
Good luck with the building.
I will be in Niseko from mon 28th jan til Friday feb 8th if that's where you are headed and want to ride a few chairs.
falls wrote:Hey Sonny.
Good luck with the building.
I will be in Niseko from mon 28th jan til Friday feb 8th if that's where you are headed and want to ride a few chairs.
Alright, great place to ski. We'll start with 2 weeks in Niseko starting 3th jan, but plan to move on down to the nagano/hakuba area after that for bigger mountains
skidesmond wrote:What is the core made of in the above pic? Looks like poplar? And the sidewall? I have a wood core that looks similar, poplar with ipe sidewall.
6 weeks of skiing? Awesome!
It's poplar and abachi with bamboo sidewalls. Yes, six weeks of awesome powder skiing in Japan! World's best pow?
Ok so the first pair came out REALLY stiff, they were meant to be superlight touring skis but are more like a touring-world-cup-carver with tip rocker kind of ski. Roughly cut our they weigh in @ 2050gram with 137-103-129 and 190cm so still not super heavy. I will probably shave of atleast 100 maybe 150g from that when they are finished.
I thought I made the core thin to match the stiffness of carbon but not nearly enough. Tonight i put my "powder" skis in the press but first i profiled down my cores to 9mm at thickest points. I hope that will make for a softer and lighter ski.
My girlfriend are making us spend the weekend at her parents place 500km from here so finishing up the skis will have to wait...
Anyhow, I'll post pictures when i get the chance to finish up the skis
