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Posted: Tue Mar 25, 2008 10:43 am
by Jared Haehnel
Right thats what I meant.. sorry. :oops:

Posted: Tue Mar 25, 2008 11:00 am
by SpudUke5
Its ok, thats what we do here (as you know) look out for each other :wink:

Posted: Tue Mar 25, 2008 11:40 am
by rcman50166
Well what kind of densities are we talking about. I'm aware the material exists, but have never found a use for it. If I were to make it, what mixtures should I use. Also how much stronger than galvanized steel is it, if any. Honestly, I don't think I'll even attempt to make one unless some impressive stats are mentioned.

Posted: Tue Mar 25, 2008 11:48 am
by judgment_arms
If you’re talking about Pykrete, during WWII the Allies were experimenting with an aircraft carrier made from the stuff.
In a demonstration a block of Pykrete was shot, the bullet just ricocheted off.

Posted: Tue Mar 25, 2008 11:50 am
by Jared Haehnel
I've never made but what from what I've read (mostly on this site) is that it is pretty strong stuff. It would be easier to make then concrete. I don't know about stronger then concrete but it would be at least close to it. but It would be very strong. As for density it is less then that of galvanized steel. But so is concrete for that matter...
The advantage is that you can make it to best fit your barrel and since its frozen water you wait a minute or to before you launch and it will have low friction as it slides down the barrel.

Edit: Look here http://en.wikipedia.org/wiki/Pykrete

Posted: Tue Mar 25, 2008 11:56 am
by judgment_arms
Jared, the stuff is like reinforced concrete.

I’d wager that a large enough bullet of Pykrete could punch though ¼ inch steel plate, at the very lest make a nice, BIG, dent.

Posted: Tue Mar 25, 2008 12:01 pm
by SpudUke5
rcman50166 wrote:If I were to make it, what mixtures should I use?
From my information, that i previously studied from a different topic, the best mixture is 14% sawdust, and 86% water. So in a 100ci container, you would put 14ci of sawdust and 86ci of water.
judgment_arms wrote:during WWII the Allies were experimenting with an aircraft carrier made from the stuff.
In a demonstration a block of Pykrete was shot, the bullet just ricocheted off.
Indeed, i saw a video on this topic on metacafe, it was in a topic on spudfiles, but i dont want to find it. This stuff was strong and definately wouldnt be considered if it couldnt handle machine gun fire or types of explosions. IIRC, this project wasnt put into action because the war had already ended.
Jared Haehnel wrote:wait a minute or to
Surely you would wait longer than a minute :wink:

But also i think it takes longer to freeze because of the sawdust.

Posted: Tue Mar 25, 2008 12:13 pm
by Jared Haehnel
Look here it is very fascinating and I'm glad it was brought up...

http://en.wikipedia.org/wiki/Pykrete

Posted: Tue Mar 25, 2008 12:20 pm
by judgment_arms
LikimysCrotchus5, I don’t know about how long it takes to freeze, but I now it’ll stay frozen for a significantly longer time than regular ice.

Posted: Tue Mar 25, 2008 1:17 pm
by SpudUke5
Well i checked the wikipedia article and it doesnt mention anything about how long it takes to freeze.

But you are definitely right in that it takes alot longer time to melt. According to the article, a 1 inch piece of pykrete can support the weight of a car, which is amazing considering its only sawdust and ice. It also can handle more "crush resistance" than 21 megapascals, (3,000 psi). It is also more stable at higher temperatures because of the wood pulp.

So theres some food for thought :)

Posted: Tue Mar 25, 2008 2:17 pm
by sniper hero
that pykrete is so cool!
can anyone make pics if he made it?

Posted: Tue Mar 25, 2008 6:20 pm
by DYI
3" Pykrete slug on the far right:

Image

It went through a microwave at 400 fps and kept going, and suffered very little damage, although it chipped quite a bit at the front.

And the ratio for mixing is by mass, not by volume. Makes quite a bit of difference :wink:

Posted: Tue Mar 25, 2008 6:36 pm
by SpudFarm
i can't stop watch the propane tank thing stuff :S
do more shots with it :)

Posted: Tue Mar 25, 2008 7:02 pm
by pizlo
yeah, the five spiked one is just... well its Uber.

Posted: Tue Mar 25, 2008 7:04 pm
by SpudBlaster15
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