lightest glass that is safe to build with?

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chrismp
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Post by chrismp »

are you going to use differently angled biax? if not, why are you planning on using two layers on each side?
doughboyshredder
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Post by doughboyshredder »

biax is 0 /90 bias is 45 / -45

There is no reason to use two layers of biax, unless that is the only way to achieve the correct weight that you are going for, or if the two layers are weighted differently on their axis.
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chrismp
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Post by chrismp »

never heard of that distinction. the stores i buy at call it all biax and just state the direction of the strands.
There is no reason to use two layers of biax, unless that is the only way to achieve the correct weight that you are going for, or if the two layers are weighted differently on their axis.
thats why i was asking ;)
FrontierSkis
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Post by FrontierSkis »

I was looking to add weight, Trying to keep the costs down on my first pair and i cant seem to find any Triax close by. I will however take a look at the 2 different weighted glass and see if it has different glass orientation. Thanks for the info.
doughboyshredder
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Post by doughboyshredder »

chrismp wrote:never heard of that distinction. the stores i buy at call it all biax and just state the direction of the strands.
That is quite odd. Which store is doing that? Are they not a fiberglass supply house?
Knitted Fabrics, a process that allows the fibers to lay in a flat plain to carry loads more efficiently for greater stiffness and strength than woven fibers. Available as Unidirectional, Biaxial (0, 90), Double Bias (+45, -45), Triaxial (+45, -45, 0 or 90) and Quadraxial (+-45, 0, 90), they offer considerable advantages for designing superior performance into laminates. Knitted Fabrics are available in a variety of weaves, weights, widths and finishes to suit a wide range of applications.
http://www.fiberglasssupply.com/Product ... brics.html

best price I have been able to find also, btw. The rolls are 50" wide, so you have to cut them to your width. I just use a sawzall with an agressive wood blade. It cuts right through it like butter.
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chrismp
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Post by chrismp »

all the major suppliers here in europe do that. i have yet to come across one that calls the +45/-45 double bias.
krp8128
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Post by krp8128 »

doughboyshredder
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Post by doughboyshredder »

that's a great visual representation of the different fabrics.

Euros are weird. Ya know all the metric stuff, and everything........

;)
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Head Monkey
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Post by Head Monkey »

Here's the answer to your original question: http://www.333skis.com/failure-analysis.php

Image

Edit: fixed picture link.
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sammer
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Post by sammer »

Yikes!! How many pairs do you think 333 sold that will come back for warranty?
I'm in the habit of overbuilding, 22oz top and bottom plus 22oz binding and tip and tail reinforcements.
My skis come out a bit on the heavy side but I think that just adds to the dampening (I only really notice the weight when I'm carrying them to the car)
I've planned to build a touring setup that will be a bit lighter but will still use 19oz triax top and bottom plus reinforcements.

sam
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shopvac
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Post by shopvac »

just curious, do you guys think this was only because of the fg weights (and choice of glass) or does it have anything to do with the horizontally laminated birch plywood he uses for his cores? I know a couple builders on here have used horiz laminated cores with good results (but they probably used some heavier glass).

I am still confused, when the 333 guy says he uses 12oz bias, does he mean 45, 45 or 0, 90 orientated glass?

On a side note, has anyone seen his 3rd generation "rail" package he has designed and built to cut out the bases and the cores? I think that is a nice design. He seems to do some of the tooling and jigging very well.
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LifeisRiding
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Post by LifeisRiding »

i think he must be using 0/90 because 45/-45 would be very weak tip to tail, and only strong torrsionally

I used baltic birtch in my new snowboard prototype and it seems to be just a strong as the vertically laminated poplar cores i used before.
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LifeisRiding
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Post by LifeisRiding »

i think he must be using 0/90 because 45/-45 would be very weak tip to tail, and only strong torrsionally

I used baltic birtch in my new snowboard prototype and it seems to be just a strong as the vertically laminated poplar cores i used before.
doughboyshredder
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Post by doughboyshredder »

Head Monkey wrote:Here's the answer to your original question: http://www.333skis.com/failure-analysis.php

Image

Edit: fixed picture link.
Hilarity. I warned sinecure not to let his son ski those.

This really seriously pisses me off. If you want to put out complete garbage, then so be it, but putting out skis that are this much of a joke is negligent. I hope someone kicks the shit out of this guy.

LifeisRiding, the dumbshit used bias, which is 45/-45 so the skis had absolutely no reinforcement in the 0 degree, which is where the majority of the load on a ski or board is placed.

Shopvac, if you look at son of sinecures first pictures you can clearly see that it is double bias.

This guy is a dded joke.
krp8128
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Post by krp8128 »

doughboyshredder wrote:
Head Monkey wrote:Here's the answer to your original question: http://www.333skis.com/failure-analysis.php

Image

Edit: fixed picture link.
Hilarity. I warned sinecure not to let his son ski those.

This really seriously pisses me off. If you want to put out complete garbage, then so be it, but putting out skis that are this much of a joke is negligent. I hope someone kicks the shit out of this guy.

LifeisRiding, the dumbshit used bias, which is 45/-45 so the skis had absolutely no reinforcement in the 0 degree, which is where the majority of the load on a ski or board is placed.

Shopvac, if you look at son of sinecures first pictures you can clearly see that it is double bias.

This guy is a dded joke.
I have to agree. If he wants to market these skis for what they are (blue groomer worthy, maybe) then so be it. Problem is, in the begining he made a lot of comments on the "American" nature of his product and how other custom manufactures are ripping you off.

There is a reason there are know skis made for $333 in the US, let alone custom skis for that price; it just can't be done.

Micheal Lish may be good at setting up shops, but he obviously has very little knowledge of basic mechanics and strengths of materials. +/-45 gives you a lot of strength torsionally, but is pretty damn floppy longitudinally. Combine that with a "void free" plywood core that is glued together at the center and drilled with alignment holes this is what you get.

I hope for Michael's daughter's sake that no one is seriously injured on these skis and sues.
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