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Discussion Starter · #1 ·
Having ground my lead keel to a bright rough surface I am about ready to coat it with a two part epoxy tar product prior to applying the antifoul paint. In the past I have tried several systems none of which was 100% successful.
The epoxy tar stuck like crazy in most places but failed in others ( as did the other products/systems). As the epoxy tar is pretty easy to work with this is my preferred option.
Has anyone had similar experience or advice to offer?
 

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I guess I am wondering why you want to put an epoxy tar on a lead keel? It does not need to be water proofed. Many racers will put a layer of polyester filler and then sand and fair it.

If you are happy with the surface why not just apply anti fouling??
 

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Discussion Starter · #3 ·
A good solution

Many years ago we had a terrible time keeping bottom paint on our lead keel. We bought the boat used and the patchy texture of the keel paint was a racing no-no. I ground the paint away and went to bright lead before painting. The paint sloughed off in patches. I did this for two years and one day an old gent on the boatyard crew walked over and asked me what I was doing (actually he added some adjectives).

His response saved me a lot of work and money from then on. The gist of what he said is when you brighten the lead, you improve the chances for electrolysis between the lead alloy and the metals in the paint which leads to flaking and peeling.

My keel lead was alloyed with tin and antimony. The bottom paint had copper and tin.

He had three recommendations:
First let the keel oxidize to flat dark grey before painting. The lead oxide coating prevents the electrolysis. Second, use a paint without tin. Third if I was in a hurry use epoxy tar on the lead.

Since I had brightened the lead and I was in a hurry (it was mid season) I used the epoxy tar. In the remaining 15 years I never had to give the keel extra attention again.
 

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Discussion Starter · #4 ·
Thanks for the replies:
Gary: The reason for the epoxy tar is because when I used bottom paint ( with an 'etch' primer') on the lead it flaked off, big time.
The epoxy tar seems to stick to the lead better and is compatable with bottom paint (i.e. it sticks to it).
DynaMeme: I gather then going straight onto the bright lead with epoxy tar worked for you??
 

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Gary M said:
If you are happy with the surface why not just apply anti fouling??
An unencapsulated lead keel will rust like crazy with rust booms erupting through the paint in a short time. Anything that can be done to retard this process will extend the paint's lifespan.
 

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Discussion Starter · #6 ·
Lead rust?

Fstbttms said:
An unencapsulated lead keel will rust like crazy with rust booms erupting through the paint in a short time. Anything that can be done to retard this process will extend the paint's lifespan.
It may oxidize, but it sure ain't gonna rust!
 

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Discussion Starter · #7 ·
Soutie said:
Thanks for the replies:
Gary: The reason for the epoxy tar is because when I used bottom paint ( with an 'etch' primer') on the lead it flaked off, big time.
The epoxy tar seems to stick to the lead better and is compatable with bottom paint (i.e. it sticks to it).
DynaMeme: I gather then going straight onto the bright lead with epoxy tar worked for you??
Yep, we just wiped the keel with MEK and were careful not to lean against it or touch it aftew we did to avoid recontaminating the surface with body oils, sweat, and boat yard grime.
 

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"An unencapsulated lead keel will rust like crazy"
OK, Pull it over and surrender the bottle!

And if there's no bottle, please report to sick bay, you've got heat stroke. (No fun sailing THIS week!)
 

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Guess I learned something new.

DynaMeme's explanation makes a lot of sense. Whenever I have painted a bare lead keel it was already oxidized so I had not trouble. Current keels I have applied a filler to get a very fair finish so again no problems.

Thanks
Gary
 

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Soutie,

I used the Interlux Interprotect 200E on our current bottom including the keel and it hasn't shown the least defect after three seasons. I recommend the Interprotect due to the ease of mixing and applying. Given the hard work that goes into prepping for this application it's critical to follow Interlux's instructions to the letter, and in particluar using the metal prep solvent that interlux sell for this purpose. (It may cost an outrageous $50 a can, but you only need one can...).

See http://www.yachtpaint.com/usa/default.asp

I've also used the straight West epoxy on two iron keels and they also held up completely, other than if you ding 'em. I think the West epoxy is a little harder to handle for big jobs.

Do it right and you'll never need to do it again.
 

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Discussion Starter · #13 ·
MEK not Acetone

Folks, I'm a chemical engineer. Acetone shouldn't be sold over the counter. The molecules are small enough they are absorbed through the skin and through some rubber gloves.

Acetone causes both acute and permanent nerve and kidney damage--it will flat out destroy your eyes if you get a splash.

MEK, Methyl-Ethyl Ketone will perform the same de-greasing function with far less risk as the molecules are too large to be absorbed. It is still a significant eye hazard.

Even so, use it in a well ventilated space or with a respirator. MEK will damage the alveoli in the lungs if breathed in high enough concentrations or for long enough.

Eye protection please and always open the container with it pointing away from you.
 

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DynaMeme said:
Folks, I'm a chemical engineer. Acetone shouldn't be sold over the counter. The molecules are small enough they are absorbed through the skin and through some rubber gloves.

Acetone causes both acute and permanent nerve and kidney damage--it will flat out destroy your eyes if you get a splash.

MEK, Methyl-Ethyl Ketone will perform the same de-greasing function with far less risk as the molecules are too large to be absorbed. It is still a significant eye hazard.

Even so, use it in a well ventilated space or with a respirator. MEK will damage the alveoli in the lungs if breathed in high enough concentrations or for long enough.

Eye protection please and always open the container with it pointing away from you.
I don't believe that Acetone is skin-absorbtive, after reading the MSDS on it. You can find the MSDS for Acetone at http://www.bu.edu/es/labsafety/ESMSDSs/MSAcetone.html

I also discussed this with a chemical engineer, and he also agrees that it isn't skin-absorbtive, I'd like to know where you're getting your information from.
 

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And here I'd been told by a number of people--including a chemist--that MEK was a very dangerous carcinogen but acetone was comparatively safe. Heck, isn't it still sold and used as fingernail polish remover?
 

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Old old thread BUT when you make moonshine the first part of the run is Acetone...cant be that bad! (but you throw it out or save it for around the house or boat).

I will continue to use Acetone with rubber gloves, NOT MEK.

-Dan
 
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