Spoon bases?

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gav wa
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Spoon bases?

Post by gav wa » Fri Feb 02, 2018 9:08 pm

Hey the folks. So i just pulled a super cool swallowtail powder board and i totally stuffed up my temp ramping and with the new resin i am trying out it has come out with a fair amount of edge high convex in the base. Edges up if you sit the board down on a table.
I can grind the base but not grind it flat, it has about 2mm per side of rise.
So I'm wondering if any of you guys have had similar and cleaned it up still and rode it? Was it a pig to ride or was it not as big a problem as it first appears?
This is a powder board so in powder i think it could be a real weapon, but the board was designed to be able to carve groomers pretty hard too, so on groomers the base convex will certainly be felt.

I've seen a few companies purposely doing raised edges now, Rossignol even do boards with raised edges all round.

So lets here the stories fellas, I'm sure im not the first fool to make this stuff up :D :D

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Akiwi
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Post by Akiwi » Sat Feb 03, 2018 3:59 am

Some of the worlds best inventions were results of mistakes! ;-)
But I can't add anything constructive about raised edges, other than it will be easy to initiate turns, and on the powder will be a blast. Just carve it everywhere and it suould be fine.
I am nobody. Nobody's perfect, so I must be perfect.

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Dr. Delam
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Post by Dr. Delam » Sun Feb 04, 2018 2:39 am

I have experimented a bit with convex bases. I shimmed my mold to achieve the desired effect. The skis were designed for powder mainly but they skied well in all conditions and they performed better than anticipated carving on hard snow.

The only drawback I found was they were very difficult to get a clean tune with a belt sander and of course stone grinding not worth even trying. They would need to be hand sanded and base edge filed.

After skiing them for awhile and hitting lots of rocks, I decided to repress them flat. I heat them a little higher than normal pressing temp and let them fully cool under pressure. I have also done this successfully changing a cambered ski into a rockered ski. I have had great success with QCM/Forrest Epoxy doing all sorts of things that I probably shouldn't do.

Go out and ride this sucker! I think you will be pleasantly surprised. If I had a machine that I could tune convex bases on I would make more skis like this. Maybe I'll try modifying my Grindrite platen with a shim to see if it works. If you don't like the way it rides, try repressing to get it flat.

gav wa
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Post by gav wa » Sun Feb 04, 2018 5:24 am

Thanks for the responses.
I think in powder this board would be really nice to ride.
Unfortunately its not for me but i guy wanting it to also ride quick down groomers. I think speed won't be an issue on firm snow but he will need to keep it on edge.

Interesting point DR regarding repressing.
I have done the same before to correct a camber issue. I have been wondering about leaving a board under pressure to cool. The board I'm working on at the moment was actually nice and flat when i pulled it hot from the press.
1 day on it's side and it was proper convex.

I grind by hand so i should be able to grind it ok, so i think you've sold me on seeing how it goes.
I repressed it a little and got it to about half as bad as it was so not a huge convex shape now.

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chrismp
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Post by chrismp » Sun Feb 04, 2018 5:49 am

I wouldn't worry too much about resort performance. I've ridden a few boards by Bataleon and they charge down the mountain like any other flat board.

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Dr. Delam
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Post by Dr. Delam » Mon Feb 05, 2018 2:55 am

I just checked out the Bataleon website and that base technology looks sweet. I also learned that the Wintersteiger machines can adapt to 3D base designs so I stand corrected about machine tuning convex boards. Wish I had one of those in my garage.

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chrismp
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Post by chrismp » Mon Feb 05, 2018 10:54 am

We have one of those wintersteigers with the three part feed rollers, but it really only adapts to designs like the Bataleon boards with bases that are comprised of multiple straight parts and not continuously bent curves. Still a pretty sweet machine :)

gav wa
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Post by gav wa » Mon Mar 12, 2018 8:42 am

The board ground up pretty nice and i only gave the edge a 1 degree base bevel, considering the extra base angle it seemed a fair idea.
It all worked really well. It is a full swallowtail powder board but with a long shallow camber.
It was a real smooth ride in every type of snow. I even received a photo from the owner showing his ski tracker reading 94kph. Good pace for a 149cm swallowtail.

So now i just got to build one for myself.

Dtrain
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Post by Dtrain » Wed Mar 14, 2018 8:14 am

I’ve made boards like that, if you even notice it will be a benefit. I’ve actually got a platten for my base grinder tnhat is machined convex. So on the last few passes of material removal, you can take more more off the edges to make it base high! I’m starting to prefer it!

24Dave
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Post by 24Dave » Fri Mar 23, 2018 8:05 am

2mm on a board, that's about perfect. My old mold made that, new one doesn't so base prep is easier. But that series of boards were all great.

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