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Recoating carbon mast

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Recently acquired a 2004 Bongo, and the carbon mast & boom's exterior clear coat is flaking off in large swaths. The carbon on both spars is in excellent shape, and I have covered the entire rig and hull now since acquisition.

What would be my potential repair/remediation options? Best products to use?

 

Bubbles and the clear coat flaking can be seen in the attached pic.

 

 

00X0X_aJIVfrTJpVU_600x450.jpg

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Clear  coat never lasts long .

a paint finish , white awlgrip or similar , lasts forever .

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Best option is sanding and paint.  If you do want the carbon look you can clear-coat but do yourself a favor and use a high quality clear like Awlgrip.  The colored vs clear lifespan (using Awelgrip) is probably in the order of 2 or 3:1.  I have had Awlgripped carbon sticks looking great for about 8-10 years before having to re-do.  If you choose Awlgrip - follow the directions to the T or it will be severely compromised.

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Ahh the Bongo! Haven't heard anything about those things in years. Saw one sailing around Sarasota Bay sometime around 2004 or 2005 and never saw them since lol. 

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Use razor blades to scrape old clear coat and sand (lightly). Wear a respirator, long sleeves and gloves. It'll be itchy.  That will be most of the work. Solid color Awlgrip is the way to go. You can roll and tip to get a good finish, but spray is probably best. If you can, coat it indoors if in a controlled temperature environment to avoid variability in the finish due temperature changes, issues with bugs and dust, and issues with condensation causing it to haze if you leave it to dry overnight. 

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Take a look at the 2k paints in a can. The Spraymax 2k Clear I have used works fantastically for a home job. If you can get a professional to shoot white Awlgrip that is a great option. We have masts here approaching 20 years old shot in white Awlgrip and the finish is holding up just fine.

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1 hour ago, samc99us said:

Take a look at the 2k paints in a can. The Spraymax 2k Clear I have used works fantastically for a home job. If you can get a professional to shoot white Awlgrip that is a great option. We have masts here approaching 20 years old shot in white Awlgrip and the finish is holding up just fine.

+1 on the 2k. Can get it in colors if you don't feel like redoing it as often. (All clear coat fails faster than paint, in my experience.)

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Looks like Lake Mission Viejo... Don't use razor blades. Wet sand with 220 and rattle can it w/Spar Varnish.

Cheapest and easiest method. It will last if covered. If you don't cover it, paint as mentioned above to withstand the elements longer.

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4 minutes ago, Irrational 14 said:

Looks like Lake Mission Viejo... Don't use razor blades. Wet sand with 220 and rattle can it w/Spar Varnish.

Cheapest and easiest method. It will last if covered. If you don't cover it, paint as mentioned above to withstand the elements longer.

You beat to it, don’t use a blade, just sand it properly. 

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If its already flaking, razor blades are going to be quicker in getting the bulk of it off. It's lot of sanding otherwise and it seems like you end up removing more of the carbon.

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scraping is good, then finish with 220, once the fibers are exposed I suggest a flowcoat of epoxy as a base. You can either use a clear 2 pk primer over that or go to a varnish system, if clear primer then you can use a 2 pk clear to finish. In Cali it will last ok, if covered most of the time, maybe easier as less fairing is required. I'd suggest a clear UV resistant epoxy.

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I gave been researching the paints that have been recently developed that have great heat reflecting properties. I couldn't believe that Hugo Boss had black paint and decals on deck especially when these boats go through the tropics. I discovered that they use a special white primer underneath all the dark black and grey graphics to help with that. Seems to be this BASF product.

https://www.dispersions-pigments.basf.com/portal/basf/ien/dt.jsp?setCursor=1_556379_820695

    I showed it to my mast builder who has convinced my client to paint his carbon fiber wing spar white but he was skeptical. He did a good job explaining how clear coat carbon was a liability in the long run for the spar and I have tried to come up with a compromise by suggesting that the spar get the BASF white heat sheild primer and then White Awlgrip as suggested by the mast builder and then we can apply some faux carbon boat wrap graphics with the boat name for a nice protective finish over the CF reinforcements and still get the 'look' of the clear coat carbon fiber that is all the rage.

http://www.dispersions-pigments.basf.com/portal/basf/ien/dt.jsp?setCursor=1_559806

There is a reason why you don't see modern composite sailplanes in anything other than white! 

http://www.dispersions-pigments.basf.com/portal/load/fid560473/Cool down your paints - Xfast_ stir-in pigments forsolar heat management.pdf

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On 08/03/2018 at 11:18 PM, DSE said:

If its already flaking, razor blades are going to be quicker in getting the bulk of it off. It's lot of sanding otherwise and it seems like you end up removing more of the carbon.

I’ve never, ever heard scraping used as a way to remove old 2 pack coatings from a mast.  Just sand it properly with a machine, like any other pro would. It’s not difficult to gauge touching the carbon, far more control than a scraper.  That sounds old practice from taking varnish of wood. 

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9 minutes ago, Rasputin22 said:

I gave been researching the paints that have been recently developed that have great heat reflecting properties. I couldn't believe that Hugo Boss had black paint and decals on deck especially when these boats go through the tropics. I discovered that they use a special white primer underneath all the dark black and grey graphics to help with that. Seems to be this BASF product.

https://www.dispersions-pigments.basf.com/portal/basf/ien/dt.jsp?setCursor=1_556379_820695

    I showed it to my mast builder who has convinced my client to paint his carbon fiber wing spar white but he was skeptical. He did a good job explaining how clear coat carbon was a liability in the long run for the spar and I have tried to come up with a compromise by suggesting that the spar get the BASF white heat sheild primer and then White Awlgrip as suggested by the mast builder and then we can apply some faux carbon boat wrap graphics with the boat name for a nice protective finish over the CF reinforcements and still get the 'look' of the clear coat carbon fiber that is all the rage.

http://www.dispersions-pigments.basf.com/portal/basf/ien/dt.jsp?setCursor=1_559806

There is a reason why you don't see modern composite sailplanes in anything other than white! 

http://www.dispersions-pigments.basf.com/portal/load/fid560473/Cool down your paints - Xfast_ stir-in pigments forsolar heat management.pdf

Thanks for the link to the paints, interesting.   

But for the mast it Seems a lot of extra work and weight all for wanting a ‘clear carbon’ finish. Just paint it white and save time/money and weight. Just my thoughts on it. 

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My mast builder was skeptical on the BASF product probably more for the cost than anything else. But when you are using high price structural materials like CF I think it would be a good idea to take any measures to keep the heat and UV to a minimum, especially for a spar destined to a service life in the tropics. I'll see what specifics I can find for the BASF products but the additive sounds promising. I first heard of these heat resistant coatings from where they were being used to paint shipping containers where they were being used for housing.

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2 hours ago, Rasputin22 said:

I gave been researching the paints that have been recently developed that have great heat reflecting properties. I couldn't believe that Hugo Boss had black paint and decals on deck especially when these boats go through the tropics. I discovered that they use a special white primer underneath all the dark black and grey graphics to help with that. Seems to be this BASF product.

https://www.dispersions-pigments.basf.com/portal/basf/ien/dt.jsp?setCursor=1_556379_820695

    I showed it to my mast builder who has convinced my client to paint his carbon fiber wing spar white but he was skeptical. He did a good job explaining how clear coat carbon was a liability in the long run for the spar and I have tried to come up with a compromise by suggesting that the spar get the BASF white heat sheild primer and then White Awlgrip as suggested by the mast builder and then we can apply some faux carbon boat wrap graphics with the boat name for a nice protective finish over the CF reinforcements and still get the 'look' of the clear coat carbon fiber that is all the rage.

http://www.dispersions-pigments.basf.com/portal/basf/ien/dt.jsp?setCursor=1_559806

There is a reason why you don't see modern composite sailplanes in anything other than white! 

http://www.dispersions-pigments.basf.com/portal/load/fid560473/Cool down your paints - Xfast_ stir-in pigments forsolar heat management.pdf

Interesting.  Reading the info in the link it would appear to be a coating ON TOP of the black paint and reflecting the IR rays before hitting the paint and cooking the surface.  This makes sense to me as it would be impossible to block the heating by adding a primer underneath the dark/black paint.  Given the way it works it would help keep a clear coate carbon structure cooler by filtering out IR rays but would do nothing for UV, which is what breaks down the epoxy matrix holding the carbon together

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I agree Christian, must be on top.

White Awlgrip looks fantastic and lasts at least 25 years in more benign climates. Its my choice if you have one, but I'd rather have my rig protected than worry about the look.

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I've painted my carbon mast with Interlux Perfection 2 part polyurethane and it's amazingly easy to apply for the amateur (as opposed to Awlgrip) and looks great.

Cheers, Greg

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