pop

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MadRussian
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pop

Post by MadRussian »

hopefully somebody can point me to the right direction. thx

couple friends reported my skis don't have any pop I like it that way but... need to give the people what they want lol

construction: symmetrical 3x fiberglass and CF tow top and bottom Maple popular core. Zero camber

What is best way to get more pop? Stiffer skis. More/different carbon fiber.. add camber?
I have not failed. I've just found 10,000 ways that won't work.
Thomas A. Edison
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backyardskier
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Post by backyardskier »

The more camber in the ski the bigger the pop.
MadRussian
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Post by MadRussian »

that's what I thought.

With GTow I can only use so much.

Carbon fiber uni tape? probably 2 or 3 inches wide

3x CF instead of fiberglass?

What to expect from those changes?
I have not failed. I've just found 10,000 ways that won't work.
Thomas A. Edison
gozaimaas
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Post by gozaimaas »

Dont worry about carbon, the camber is what will make the difference. Do the heat mat differential and see what you get, 20°c hotter on the bottom for the entire cycle.
MadRussian
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Post by MadRussian »

now I'm totally confused.
I have not failed. I've just found 10,000 ways that won't work.
Thomas A. Edison
mammuth
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Post by mammuth »

Asymetrical heating: more or less camber. If you dont want to change your mold (you have 0 camber, no?), you can try to get some camber with this trick.
Tom
MadRussian
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Post by MadRussian »

you are correct I don't want to make changes to 0 camber mold. If to create camber first I will do asymmetrical heating ....it has some challenges because I didn't want to bring bottom blankets about 160° F. But this is not the question at this time.
My reply about confusion is because I received advice on two different directions one suggest put more carbon another suggestion add camber
I have not failed. I've just found 10,000 ways that won't work.
Thomas A. Edison
gozaimaas
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Post by gozaimaas »

A flat plank of wood will push either way with little force,this is responsible for the dull feeling that your friends are reporting, a pre bent one has stored energy and will spring back like a bow (and arrow). That right there is pop and it really makes the board or skis come to life.
I too use a flat mold and pull camber with heat differential. It works amazingly well.
MadRussian
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Post by MadRussian »

I understand that. It difficult to believe that 5 to 8 mm camber can create that pop they're looking for.
goz have you done same/similar skis or board with or without camber to compare?
If camber is a key that easily can be fixed. How much camber do I need?
I have not failed. I've just found 10,000 ways that won't work.
Thomas A. Edison
gozaimaas
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Post by gozaimaas »

Unless your cores are soggy noodles to begin with which I doubt that little bit of camber makes all the difference mate. I've played around a lot with this stuff, pushing the boundary till I push too far. Ive got boards that are flat, rocker, camber/rocker/camber, mild camber and too much camber lol.
I have lots of pretty boards that were ridden once and resigned to wall hangers but the knowledge I gained is worth it, my boards are spot on now, as good as anything I've ever been on and the people who ride them are blown away.
Nothing feels as dead as flat, nothing is as hard to ride as too much camber, somewhere in the middle lies perfection and for me its the 20°c temp differential that delivers.
Prak
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Post by Prak »

Goz, how does asymmetrical heating affect the tip/tail shapes in comparison with the mould?
I can picture the tips dropping in height as the camber rises, but does it affect any radius/angles in the tips?
gozaimaas
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Post by gozaimaas »

I don't notice substantial pull in the tip or tail but I dont really check either. You might get 1% variation.
gozaimaas
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Post by gozaimaas »

another thing I should post is that I have a feeling the time differential does more than the heat differential. Because the bottom mat fires up first it pulls it that way, I reckon you could finish them at the same temp and still get the camber as long as you maintain the temp differential as they warm up.
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falls
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Post by falls »

The last pair I made were a 181cm. Started bottom heat first and then started top when bottom had reached 20C above ambient temp (as per conversation with gozaimas). Then cooked bottom at 85 and top at 80C. Generated about 4-5mm camber over a 1175mm flat section in the mold. Tip rocker was def affected. Tip height should have been 7.3cm, but ended up about 6cm. A little higher if you depressed the camber but still lost at least a cm in tip height. Not a big deal as 6cm is still adequate.

Flat camber skis have no pop. But I don't feel like pop is a powder thing which is what flat camber excels at.
Need camber for pop. It's the rebound out of a turn or off a jump that the camber provides. Carbon in a cambered ski can help add pop as it helps the ski snap back to its desired shape rapidly.
Don't wait up, I'm off to kill Summer....
gozaimaas
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Post by gozaimaas »

The biggest variable that will effect how much camber you get is how thick/stiff the core is.
Mine are really thin, between 6mm and 7mm so I get more than 5mm camber. Its something you just need to play with to perfect.
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