Ask Sail: Cetol Skin

I used Sikkens Cetol on the bare wood on my Catalina 30, Morning Dew IV. The can was compromised over the spring, and I put the balance in a 16oz clean glass mayo jar. Last spring when I went to use it, a skin had formed over the top of the liquid, so I just cut the skin off. It is 1/8in thick. In the future, is it still OK to use?
Author:
Publish date:
Social count:
0
I used Sikkens Cetol on the bare wood on my Catalina 30, Morning Dew IV. The can was compromised over the spring, and I put the balance in a 16oz clean glass mayo jar. Last spring when I went to use it, a skin had formed over the top of the liquid, so I just cut the skin off. It is 1/8in thick. In the future, is it still OK to use?

CETOL SKIN

I used Sikkens Cetol on the bare wood on my Catalina 30, Morning Dew IV. The can was compromised over the spring, and I put the balance in a 16oz clean glass mayo jar. Last spring when I went to use it, a skin had formed over the top of the liquid, so I just cut the skin off. It is 1/8in thick. In the future, is it still OK to use? How can I store it better?

Steven Berlin, Pine Point, ME

Don Casey has written many books and articles on marine maintenance and repairs

Don Casey has written many books and articles on marine maintenance and repairs

Don Casey Replies

When any liquid coating forms a skin in the can, its chemistry is changed. This is especially a problem with Cetol, which the manufacturer cautions against thinning. Whether what you have remaining in the can is still suitable for use depends on how much of the solvent has been lost. If the finish goes on thin and smooth with your brush, it is probably fine, but if it seems thick or the brush drags, I would not run the risk. As for storing it, there is no container better than the original can, because it clearly identifies the contents and has all the instructions and warnings. But once you let air into the can, and particularly as the ratio of air to liquid increases, a skin will form. To prevent this, I use a product called Bloxygen (bloxygen.com), an inert gas (argon) in an aerosol can with a thin feed tube. Making sure first that the rim of the can is clean, you put the lid in place with the feed tube between lid and can. A two- or three-second squirt of Bloxygen then displaces some of the air, replacing it with argon, which is heavier. Remove the tube and press or hammer the lid home. The heavy argon settles on top of the liquid in the can like a gas blanket. Because it is inert, it does not react with the liquid, so the can’s contents should enjoy the same shelf life as an unopened can. Supposedly a single can of Bloxygen can be used 75 times, but in my experience this is optimistic. Nonetheless, throwing out a single half can of Cetol (or varnish) is a $15 loss at a minimum, which makes an $11 can of Bloxygen an exceptional bargain, even if you only use it 30 times.

bloxygen-FPO

Got a question for our experts? Send it to sailmail@sailmagazine.com

Related

SuperFoiler_2018_Adelaide_0325

Foiling Multihulls Take Their Toll

Although sailing has always been inherently dangerous, it’s becoming increasingly obvious that in addition to elevating boatspeeds, today’s foiling multihulls are also dramatically upping the level of risk. In the run-up to the 35th America’s Cup, regatta organizers were fond of ...read more

TOTW_PromoSite

SAIL's Tip of the Week

Presented by Vetus-Maxwell.Got a tip? Send it to sailmail@sailmagazine.comA Double Winner Off on a longer trip than usual next summer? If so, you may well end up carrying extra fuel in jerry cans on deck. However, lashing them to your stanchions is a thoroughly bad idea, because ...read more

tasha-fuiaba-2

Waterlines: Auto-da-Fé

Why must we persecute bluewater cruisers who get into trouble?It has become standard operating procedure. As soon as the online sailing community catches word of a cruising sailboat that has been abandoned offshore, the crew of said boat is immediately subjected to a cyber ...read more

01_arc17-2079

ARC: Slow Road to St. Lucia

In the curtain call of an Atlantic crossing that had proved frustratingly slow for many of the 186 participants in the Atlantic Rally for Cruisers (ARC), the 37ft classic wooden sloop Trimley Maid crossed the finish line in Rodney Bay, St Lucia, on Christmas morning, over a month ...read more

c45-style-renex-03

Just Launched: Bavaria’s New Look

Having had maximum use out of its Cruiser line of Farr-designed hulls, Bavaria Yachts is in the process of renewing its entire range. The first of the new-look Bavarias designed by Mario Cosutti, the C57, debuted at Boot Dusseldorf last year and has now been joined by two new ...read more

Humpback-next-to-the-yacht

A Circumnavigation of Vancouver Island

A circumnavigation of Vancouver Island? That sounded like a great idea, so after a few months of planning, my friends Bridget, Jelski, Jonty and I quit our jobs in Auckland, New Zealand, and flew to Canada, where we joined Harry Miller and Sarah White aboard their 1983 Canadian ...read more

baths1

A Quick Recovery in the BVI

At 0730 on the morning of December 6, three months to the day after Hurricane Irma’s eye tracked across the British Virgin Islands, I clambered up into the helm station of our Moorings 4500, stretched and looked across at the white sand beach of Great Harbour on Jost van Dyke. ...read more