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      Abbreviated rules   07/28/2017

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Two Coats of Papaya Juice, Sir?

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The Biz

 

Two Coats of Papaya Juice, Sir?

 

Environmentally-Friendly Enzyme Based Antifouling Paint? An enzyme-based antifouling paint has been developed that utilizes biodegradable fruit enzymes derived from papaya and pineapple as the active ingredients in place of conventional biocides of commonly used heavy metals and highly toxic chemicals such as tributyltin (TBT) and cuprous oxide. Currently the International Maritime Organization (IMO) is conducting a worldwide five year phase out of the widely used TBT by January 1, 2008 . Comments?

 

01/29/07

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TBT has been banned , in N.S.W. at least, for a long time now, it was also blamed for ending the Sydney district Oyster Industry,

 

rec Divers here are reporting more shellfish activity on the seabed under the mooring farms

 

Copper is considered the lesser of the two evils.

 

 

Ed,

can the P'paya go over the P'apple paint and be burnished ?

heard that P'apple is ok over P'paya, can be brushed if thinned with Cranberry (shaken not stirred) and has a more ablative property.

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The Biz

 

Two Coats of Papaya Juice, Sir?

 

Environmentally-Friendly Enzyme Based Antifouling Paint? An enzyme-based antifouling paint has been developed that utilizes biodegradable fruit enzymes derived from papaya and pineapple as the active ingredients in place of conventional biocides of commonly used heavy metals and highly toxic chemicals such as tributyltin (TBT) and cuprous oxide. Currently the International Maritime Organization (IMO) is conducting a worldwide five year phase out of the widely used TBT by January 1, 2008 . Comments?

 

01/29/07

 

The rest of the story

http://www.treehugger.com/files/2007/01/shiver_me_timbe.php

 

The other day we ran a review on The Doggy Dung Disaster, a book about 30 inspirational kids from around the world. One of those profiled is Vaishali Kiran Grover who was 14 when she was awarded $1,500 USD in the 2002 Intel International Science and Engineering Fair. She garnered the award for her environmental science project, in which she discovered that snails near her family’s papaya tree were dying, and she wondered if the same might hold true for marine mollusks, such as barnacles that attach themselves to the hulls of ships (slowing their movement). Her research led to a biodegradable enzyme treatment using papaya and pineapple. It offers an alternative to the usual anti-fouling paint that commonly contains heavy metals and toxic chemicals like cuprous oxide and tributyltin (TBT). The latter is something the International Maritime Organization (IMO) is hoping to phase out by about this time next year. In 2003 the US Navy awarded her a $8,000 scholarship for “original research in an important Naval-relevant scientific area.” As recognition for her work, Vaishali had asteroid 17950 named Grover after her! How’s that for 15 minutes of fame? The National Gallery For America's Young Inventors inducted her in 2004, where she has a comic telling her story. Or read Vaishali’s story in a free PDF excerpt from The Doggy Dung Disaster.

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Go with the papaya bottom coat. It is faster than the pineapple because it is more orange.

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I have been giving this much thought; and I've had the time on my hands to play with it a bit....(I meant with bottom paint)... I'm not completely convinced "enzymes" will keep the bottom from fouling up, but what I think will work is based on a technology I worked on as a Chemist for a pharma company.

 

We were making a polymer that looked like a super thick maple syrup that was designed to "melt" in the body at a very predictable rate. This goo could be altered a bit and the rate of decay would change. I am taking a similar goo and using a molecular weight protein of about 50,000 (as per Marchav...from the book the aero hydrodynamics of sailing) and suspending the protein in the goo...

 

as the goo decays, the protein is released, and the boat's drag coefficient is lowered. I bet the crap would probably be made illegal as far as racing goes.... but the take home message is it is possible (and cheap) to make a non toxic ablative bottom finish....

 

anybody want to start a business?

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I have been giving this much thought; and I've had the time on my hands to play with it a bit....(I meant with bottom paint)... I'm not completely convinced "enzymes" will keep the bottom from fouling up, but what I think will work is based on a technology I worked on as a Chemist for a pharma company.

 

We were making a polymer that looked like a super thick maple syrup that was designed to "melt" in the body at a very predictable rate. This goo could be altered a bit and the rate of decay would change. I am taking a similar goo and using a molecular weight protein of about 50,000 (as per Marchav...from the book the aero hydrodynamics of sailing) and suspending the protein in the goo...

 

as the goo decays, the protein is released, and the boat's drag coefficient is lowered. I bet the crap would probably be made illegal as far as racing goes.... but the take home message is it is possible (and cheap) to make a non toxic ablative bottom finish....

 

anybody want to start a business?

 

A chemist? That explains a lot. Sniffing too much of the ether eh? :)

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as the goo decays, the protein is released, and the boat's drag coefficient is lowered. I bet the crap would probably be made illegal as far as racing goes.... but the take home message is it is possible (and cheap) to make a non toxic ablative bottom finish....

 

anybody want to start a business?

 

It already is illegal.

 

53 SKIN FRICTION

A boat shall not eject or release a substance, such as a polymer, or

have specially textured surfaces that could improve the character of

the flow of water inside the boundary layer.

 

 

No.

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It already is illegal.

 

53 SKIN FRICTION

A boat shall not eject or release a substance, such as a polymer, or

have specially textured surfaces that could improve the character of

the ?ow of water inside the boundary layer.

No.

 

 

I'm guessing the papya stuff is ablative, and if that is the case it may change the drag coefficient of the boat. There are ablative bottom paints on the market now... seriously... does anyone know how these finishes affect the hulls drag coefficient?

 

I'm guessing with the metals stuff the molecules were small enough they would not effect the boundry layer, but I'm sure enzymes have a molecular weight over 50,000. That rule may have to change.

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