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(@Anonymous 39155)
Posts: 3112
Topic starter
 
[#24247]

I was watching the Science Channel. Impregnating kevlar body armor with a mix of polytethylene glycol and silicon makes it impervious to stabbing damage. Any application to boat building?


 
Posted : January 6, 2009 11:52 am
(@Anonymous 13274)
Posts: 3111
 

Who the hell is trying to stab your boat? <img src="<>/shocked.gif" alt="shocked" title="shocked" height="15" width="15" />


 
Posted : January 6, 2009 12:03 pm
(@powergroove)
Posts: 1224
Master Chief Registered
 

makes for shapeful bodies too


 
Posted : January 6, 2009 12:29 pm
(@_removed-account)
Posts: 15030
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Originally Posted by John Williams
Who the hell is trying to stab your boat? <img src="<>/shocked.gif" alt="shocked" title="shocked" height="15" width="15" />

LOL!!!!


 
Posted : January 6, 2009 12:33 pm
Tony_F18
(@Tony_FX1)
Posts: 2315
Captain Registered
 
Originally Posted by John Williams
Who the hell is trying to stab your boat? <img src="<>/shocked.gif" alt="shocked" title="shocked" height="15" width="15" />

Etchell sailors, thats who! <img src="<>/grin.gif" alt="grin" title="grin" height="15" width="15" />


 
Posted : January 6, 2009 12:50 pm
(@Anonymous 39155)
Posts: 3112
Topic starter
 

<img src="<>/smirk.gif" alt="smirk" title="smirk" height="15" width="15" /> There has been some complaining about dimpling and the like with kevlar construction.

More to the point, anyone who saw Gordon's A cat split in half might be interested.


 
Posted : January 6, 2009 12:51 pm
Jake Kohl
(@jake)
Posts: 11744
Three Star Admiral Registered
 
Originally Posted by Tikipete
<img src="<>/smirk.gif" alt="smirk" title="smirk" height="15" width="15" /> There has been some complaining about dimpling and the like with kevlar construction.

More to the point, anyone who saw Gordon's A cat split in half might be interested.

I don't think that has much to do with the Kevlar...rather how MUCH kevlar was used and how well it was bonded to the core. A fiberglass boat with a thin skin will dent just as easily if not more so.


 
Posted : January 6, 2009 1:35 pm
(@_removed-account)
Posts: 15030
Four Star Admiral Registered
 

as Jake notes skin dimpling has very little to do with material and a lot to do with thickness. Because you can get away with very thin skins with exotic materials you can end up with a lot more dimpling than a chop strand mat f/g boat. Higher density cores can be specified to reduce dimpling, however, this offsets some of the initial weight gain from using the high tech material.


 
Posted : January 6, 2009 4:24 pm
Matt M
(@matt-m)
Posts: 686
Member
 

Poly glycol and silicon make it so the resin will not bind to the fibers. This is how Kevlar and the other composites become ballistic and or cut resistant. The materil becomes essentialy a net that slowly defoms and catches the projectiles, where stiff material fracture quickly and therfore dispate very little of the energy.

A hull needs to be stiff. Adding a binder inhibitor to it would not only make it structuraly unsound, but the thin skin would be in effect even less resistant to denting the core.


 
Posted : January 6, 2009 4:32 pm
(@Anonymous 39155)
Posts: 3112
Topic starter
 

Just wondered. The demonstration on T.V. was very impressive. Some guy using all his strength to try and stab an awl through a kevlar vest with no success.


 
Posted : January 6, 2009 4:36 pm
(@stank)
Posts: 5061
One Star Admiral Registered
 

Don't worry, Pete. They're out with ceramic vests now. Seem to have better characteristics: Lower weight, higher impact resistance, and can defeat knives/schrapnel.


 
Posted : January 7, 2009 12:46 pm
(@Anonymous 39155)
Posts: 3112
Topic starter
 

Ceramic. . .tile. . .space shuttle. . . bullet proof boat!?

Has any tried using heavy dish washing gloves when painting or working with epoxy?


 
Posted : January 7, 2009 2:48 pm
Jake Kohl
(@jake)
Posts: 11744
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Originally Posted by Tikipete
Ceramic. . .tile. . .space shuttle. . . bullet proof boat!?

Has any tried using heavy dish washing gloves when painting or working with epoxy?

Yep - works fine. I used them for a while and worked to keep them clean so I could reuse them...I got about 10 uses out of them before they were too trashed to continue. However, I still like the vinyl or latex gloves for convenience and the lack of having to keep up with or clean them. The vinyl or latex gloves also give you more dexterity.


 
Posted : January 7, 2009 3:38 pm
(@Anonymous 13024)
Posts: 4319
 

We use double layers of vinyl gloves when working with epoxy. Makes it easy to change the gloves when they get sticky and your hands are sweaty. If you dont need that extra

surgeons touch

, heavy dish washing gloves with a vinyl set over them is the best from both worlds.
Buy vinyl gloves in bulk (a thousand), and they are cheap.

I think epoxy can work its way through latex gloves?

I just came up from the workshop after glassing a hull panel <img src="<>/smile.gif" alt="smile" title="smile" height="15" width="15" /> http://woodastic.blogspot.com/


 
Posted : January 7, 2009 4:01 pm
(@Anonymous 39155)
Posts: 3112
Topic starter
 

Size is the issue. Even large gloves are hard for me to wiggle into.


 
Posted : January 7, 2009 4:03 pm
(@Anonymous 13024)
Posts: 4319
 

Aha.. Perhaps a good set of dishwashing gloves with vinyl ones over then? Should be easier to pull on the vinyl gloves that way? The dishwashing gloves could last forever that way, and you would protect your wrists and arms from epoxy as well.
Be careful if you go with just dishwashing gloves. Epoxy can seep through some of that stuff.


 
Posted : January 7, 2009 4:09 pm
Bob Hall
(@brghc)
Posts: 671
Chief Registered
 

We always used multiple pairs of Latex surgical gloves for epoxy...sometimes as many as five pair at one time...you just strip off the outer pair as needed and keep going. They are dirt cheap and come in at least four different sizes to fit even the largest hands...
When you vacuum bagging large parts and you have a thousand dollars worth of materials at stake you don't have the luxury of stopping and changing gloves or cleaning them…

Regards,
Bob


 
Posted : January 7, 2009 6:25 pm
Jake Kohl
(@jake)
Posts: 11744
Three Star Admiral Registered
 
Originally Posted by Seeker
We always used multiple pairs of Latex surgical gloves for epoxy...sometimes as many as five pair at one time...you just strip off the outer pair as needed and keep going. They are dirt cheap and come in at least four different sizes to fit even the largest hands...
When you vacuum bagging large parts and you have a thousand dollars worth of materials at stake you don't have the luxury of stopping and changing gloves or cleaning them…

Regards,
Bob

Both are terrific ideas! I did really like how the dishwashing gloves protected further up my arm.


 
Posted : January 7, 2009 6:33 pm
(@Anonymous 37750)
Posts: 1843
 

Still leaves a hell of a bruise and in some cases organ trauma. The bonus is that the target get to live!


 
Posted : January 7, 2009 7:38 pm
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