Effects of an inbalanced layup on camber and tip/tail heights

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Cadman
Posts: 71
Joined: Tue Apr 06, 2010 9:50 am
Location: Crystal Mountain, Washington

Effects of an inbalanced layup on camber and tip/tail heights

Post by Cadman »

I am trying to figure out which way a molded ski will normally move with a layup that has two layers of glass on the bottom the same thickness and only one layer on the top. Do you think I will get less tip height or more tip height? I am curious as to how much I need to compensate for the
changes. I know that I can change the delta of the heat blankets but I would rather start with what I think will happen. From what I have read, using the temperature changes from top to bottom adds stress into the ski. Thanks.
Thelongride
Posts: 45
Joined: Thu Jun 06, 2019 8:53 am
Location: Washington

Re: Effects of an inbalanced layup on camber and tip/tail heights

Post by Thelongride »

I've played around with something similar, though opposite in layup to what you are currently thinking. I've run carbon tension layers, and a carbon/glass hybrid compression. In essence there are considerably more fiber bundles in the top layer, and the result is a fairly asymmetric layup. I haven't run into many issues curing with top and bottom heat equal. I believe part of this might be that: glass expands, carbon contracts, and UHMWPE expands when exposed to elevated temps. So we result in a VERY rough thermal stability (I have no data to prove any of this).

As a side note, I'd be a little bit worried about putting double the number of fiber bundles into tension as compression. You might push your neutral axis quite high in the core and see some compression failures. Although with full glass and hardwood you can get away with almost anything ;)
You never know until you try!
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