Puzzle Skis

Document your personal work here. Show photos, movies, and share your secrets.

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pmg
Posts: 479
Joined: Sat Dec 01, 2012 8:59 am
Location: Sonthofen

Post by pmg »

Well,

what to do if you can hardly go into the workshop because the workshop is 15mins away and you got a 4 week old baby at home?
Take everything that does not create dirt or noise home :) Much warmer there anyway...

So, I am preparing the layup here at home - base with edges and the tip/tailspacers are put in place:

Image



A closeup of the tipspacers. The material removed by the hollow tips is about 20g. Together with the 10g the hollow tail spacers save, its 30g per ski.

Image
twizzstyle
Posts: 2204
Joined: Tue Mar 07, 2006 8:25 pm
Location: Kenmore, Wa USA

Post by twizzstyle »

Did you rivet the tip spacer to the mold?

no fiberglass/epoxy under your tip spacers? What's going to hold them in place? What is going in the cutout void in your tip spacers? Foam/honeycomb?
pmg
Posts: 479
Joined: Sat Dec 01, 2012 8:59 am
Location: Sonthofen

Post by pmg »

Hi twizz,

of course there will be some fibres, in my case triax carbon 150/150/150.
Its not rivets, but screws. So when I lay up I first put VDS and the triax and then put the tipspacer on top. The screws not only help to keep the spacers in position but mostly for me to exactly know where their position is :) If that hole moves some mm, it will look really bad in the finished ski.

The hole is not filled with anything. As I press vacuum this "hole" section will be 2.5mm thinner than the surrounding material - hollow tip like Kästle does.

Cheers
twizzstyle
Posts: 2204
Joined: Tue Mar 07, 2006 8:25 pm
Location: Kenmore, Wa USA

Post by twizzstyle »

Cool, got it. I thought you had it all fixed to the mold as it will be for layup, so I was a little concerned :) Curious to see how those tips turn out, haven't seen a homebuilder do something like that before.
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vinman
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Post by vinman »

Interesting concept for the tip. You'll definitely get some kind of depression there.
Fighting gravity on a daily basis
www.Whiteroomcustomskis.com
pmg
Posts: 479
Joined: Sat Dec 01, 2012 8:59 am
Location: Sonthofen

Post by pmg »

3 Month have passed with a lot of skiing and babysitting. => No time for ski building.
Tomorrow is the day, will press the ski and see if assembling all the puzzle parts works or if it will be a big mess :)
pmg
Posts: 479
Joined: Sat Dec 01, 2012 8:59 am
Location: Sonthofen

Post by pmg »

Pressing today brought 2 things:

1) its really hard to keep all the Puzzle parts in place. The solution would be to laminate all the core parts first in a separate press cycle, but thats really too much work. So I will probably discontinue this way of building unless I find a good way of attaching the base stripes above the edge somehow.

2) A power blackout of about 15 minutes during the time the resin was curing. Pressure went down to 0... so the ski will probably be trash :(
mammuth
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Location: somewhere in the alps

Post by mammuth »

The power stuff is pita. My compressor blows the fuse from time to time so its gambling...

But 15 minutes should be no problem. On my last ski the vaac was going down from 25hg to 22hg in 40 minutes! I have a vacuum tank with 50 litres (or 25, dont remember) in between, that helps too. But 0 in 15 minutes means you have a major leak in your vaac setup
Tom
pmg
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Location: Sonthofen

Post by pmg »

Wow, a setup keeping the vacuum this well is nice! I absolutely have no Idea where the air gets in again, could be anywhere. Perhaps its really your vacuum tank: If my setup is without any vacuum, there might be at most 5l of air in there. So if 5l get back into the system my pressure is down to 0. In your system, 5l would mean losing 20% or 10% of the pressure. Do you have a pic of your vacuum tank? This might be a nice addition to my setup.

Cheers
Hannes
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Location: NRW, Germany

Post by Hannes »

So whats up with your skis? Are they trash?
mammuth
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Location: somewhere in the alps

Post by mammuth »

On my first ski the vacuum pump started every 15-20 minutes. On my last one like described. Using a normale weisse Küchenarbeitsplatte, these rubber stripes from hp and a foil from rg. U hear really small leaks if you go close with your ear.

My vaac pump (venturi system) with the tank holds the vaac very long, after 2-3 days its still around 10hg. i used a tank from an old air compressor. And i added a check valve (Rückschlagventil) between tank & pump. Will check for pics.

But still ... i dont like the vaac. To much hazzle to setup (foil, breather mesh,...) every time. Problems getting air bubbles out. Good to start (or for doing 3d, cap) but otherwise ...
Tom
pmg
Posts: 479
Joined: Sat Dec 01, 2012 8:59 am
Location: Sonthofen

Post by pmg »

Unpacked them today, the first impression was that everything is fine. Will find some time to cut em out on saturday, then I will see the result.

Regarding my vacuum, I really think its air coming back in from the pump if its switched off... No need to switch off the pump though, the power blackout really is a scenario I didnt considerate :)
pmg
Posts: 479
Joined: Sat Dec 01, 2012 8:59 am
Location: Sonthofen

Post by pmg »

So,

cut them out today and beveled sides for the top layers. Will take some pictures tomorrow.

I seem to be lucky in 2 ways

1) The power blackout didnt do any obvious damage
2) the base strips stayed in position, they really look cool :)
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Akiwi
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Location: Olching (Near Munich) Germany

Post by Akiwi »

Pictures?
Bummer that the season is now at its end.
pmg
Posts: 479
Joined: Sat Dec 01, 2012 8:59 am
Location: Sonthofen

Post by pmg »

Hi,

only have one new pic at the moment, a picture of the side of the ski prepared for pressing the next layer on it:

Image

As you can see I laid free the green base layer, routed the wood with a 30° angle, and rounded the top edge of course.

What I already did is to press the top layer of triax carbon as cap on it. Did it yesterday, will see how successful it was tomorrow. So I really decided to press the top part of the ski in 2 parts (because of the carbon being black). So for now its just carbon with whitened epoxy and peel ply, and in another press cycle design and topsheet will follow. Lots of work, but if the result is the way I want... lets see.
When I will switch to designs printed on the inner side of the topsheet, making the top of the ski will be way easier. But for now I will stick to laminating funny fabric as design. You will see why its funny when the ski is finished. Its very very hippie like :)
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