OAC 2010/11

[OAC]

What was the nazi one?

Castle Wolfenstien.

And you are Eric Wolf..... moahahhhahah
I'm just thinking of "Fronk-en-steen" from the Mel Brooks movie "Young Frankenstein".

Anyway...some update (if you care) from the OAC-ski factory.

Cutting base (with the "Base-cutter-3000"):


Edges mounted. Not the prettiest ones, but I wont ski on my tips anyway.


All for today! (Tomorrow I'm gonna introduce you to my "Top sheet-maker-3000"!)

[OAC]

Topsheet testing.
Last year I did some tries with different types of materials for topsheet. One of them was a plastic film you use if you want to cover a window (eg. bathroom window). With a pretty cool structure I thought. It was just that it came off right away. It didn't attached at all to epoxi. Fiasco!
But nevertheless it left a nice blank surface! Unwanted results becomes wanted! Always something.

[twizzstyle]

What are those graphics printed on? Rice paper? They look really crisp!

[OAC]

Just regular printer paper. On a inkjet printer (Lexmark).

[baoko]

Your vacuum set up looks fantastic. Had I seen your set up a few months before, I may have gone vacuum style. Shopvac's youtube link persuaded me convincingly.
Have you heard of Boheme in France? If not, search Boheme Skis on Youtube and you will find some links showcasing their factory and their vacuuming method.
Keep those updates coming!

[sammer]

Somehow this looks familiar.
Almost the exact same as my process!
Only he's got the good silicone vacuum blanket.
And I wetout my reinforcements on a separate table.



sam

[OAC]

I haven't seen that one. Thanks posting.
You see sam, he has an bigger (stable) frame. A success factor
I will try to do the layup on vac-table. I was close today, but I ran out of ink in the printer!.....

[skidesmond]

I haven't seen that one. Thanks posting.
You see sam, he has an bigger (stable) frame. A success factor
I will try to do the layup on vac-table. I was close today, but I ran out of ink in the printer!.....

It's always something...

[OAC]

Yeah, yeah...I'm lazy and have nothing to blame for the moment. (other than the ink in the printer... )

[baoko]

Thanks for posting the link!. In this forum, I must make 2 legit posts before I can post links. As far as I know there are 3 to 4 movies about their operation. And do visit their website. They have some inspiring top sheet design. IMO, they have the best top sheet design for lady skiers!
OAC, while browsing through many threads at the same time (my mistake), I lost track of a thread about orders of fiber layup. I think it was you who said carbon layer should be on the most bottom layer... Can you enlighten me with your thoughts or re-post your link?

[OAC]

OAC, while browsing through many threads at the same time (my mistake), I lost track of a thread about orders of fiber layup. I think it was you who said carbon layer should be on the most bottom layer... Can you enlighten me with your thoughts or re-post your link?

I don't think there are a separate thread. But I remember having a thought, theory(my) or so... It comes from discussing this with others, both skibuilders and RC plane buliders
The main idea (let's call it that) is that if you're going to use carbon fiber, use it under core. There are certain differences between fg(fiber glass) and cf(carbon fiber). Keep in mind that they come in the same type of "pattern" (twill, uni, biax, triax...). The pros of cf is: lighter than fg, and its very good in tension and bad(or poor strength) in compression.
(my)Theory one: cf under foot, good strength when in tension. And a lighter ski.
(my best )Theory two: cf under AND on top. Better strength when in tension. But also a force that want to bend the ski back to its original shape (when the cf on top is in compression). This makes the ski not unstable but with more vibrations. No fun.
(my)Theory three: A well formed core with fg under and over, maybe an extra layer under foot, will do just fine. It will be a little heavier, but cheaper!
Theory four: The best way is ofcourse testing and trying different ideas.
Most of it, is in the matrix! (what type of fiber and epoxi used)
One thing I do sometimes is that I take a thin piece of wood, 2-4 mm thick, picturing the core. And laminate it with fiber and epoxi (matrix). This will give me an idea how the characteristica of the ski will be.

But as always...theory and practic not necessary go hand in hand.

There will probably be as many theories as skibuilders.

Also search the forum and check for other similar threads. I remember "G-man" had something about "cap vs. sandwich".

If you want figures(numbers) check wikipedia.

Regards

[lucacasty]

Ciao everybody

This is a video from Boheme skis and as you can see they a re using a vacuum press similar to ours.
http://www.youtube.com/user/ArnaudB100# ... tEinQwbUGc

After my experience with vacuum now we are building a big standard press.
As soon we will be able to press the first skis I'll report about diffrences between the two technologies.
In the meantime enjoy the video.

Luca

[baoko]

OAC, thanks for the info. This is exactly what I was looking for, a little something from those who have experience. I purchased some glass and carbon fiber from HP textiles based in Germany. They have a nice store in eBay. If you have any other stores you recommend on the web, it will be greatly appreciated.
I am deciding which air compressor to buy and as soon as this decision is made off I go.

[chrismp]

hp textiles is the way to go for composites in europe afaik.
timeout.de is also a good source, but slightly more expensive. nevertheless it's the only source i know of for buying small quantities of sicomin epoxy at reasonable prices/shipping rates.

[OAC]

After my experience with vacuum now we are building a big standard press.
As soon we will be able to press the first skis I'll report about diffrences between the two technologies.

Luca

I'm looking forward to see the results!

Vive la vacuum!



And here two pictures of my "Topsheet-master-3000"! You can see where all the yellow went!!
I couldn't stop the print out. And don't even want yellow!