Tung oil, skinning in the can

[Gavlar]

Hi all,
I use tung oil quite a bit so understand it's a drying oil. When the tin gets half empty there's enough air in it to skin it over, even with the top screwed on. Is there a prevention tip, or do I just need to use it faster?!

 

[Sgian Dubh]

Some people reckon a good tip is to replace the used finish with stones or marbles. In other words, if the can is half empty, stick a bunch of marbles in until the liquid rises almost to the top of the can before replacing the lid. I've tried once or twice, but I can't say the trick was an unqualified success. Slainte.

 

[J-G]

Store it upside down ??

 

[Ollie78]

You can get nitrogen spray or other inert gasses, it is heavier than air so you spray some in the tin and it sinks down purging the oxygen which causes the drying then you stick the lid on quick.
It's how they keep crisps fresh etc. And wine that's been opened.

I have not tried it myself but apparently it works great.

Ollie

 

[Gavlar]

Store it upside down ??

I've tried that with paint in the past, but unless the skin is very thick it's not strong enough to hold the weight of the fluid when it's tipped back upright. You end up with layers of skin and paint/oil marbled through like a Viennetta. I'm leaning towards transferring to successively smaller jam jars as the can is used up. It's a right PITA!

 

[KT_NorCal]

Nitrogen or Argon... or really any heavier than air based gas. Easiest way to buy the stuff is in the cans that are sold to preserve wine. Squirt it in the wine bottle once or twice, put the cork back on. Same principal. Feels like you are buying an empty can though! There are cheaper ways to buy it in bulk, but I don't need it all that often, so works fine for me.

There are some things it won't do you much good for since once they hit oxygen then essentially a countdown starts, but for something like tung oil it should work well.

 

[thetyreman]

have you tried clingfilm? I use it with paint and it works well to prevent it drying out, creates a better more airtight seal.

 

[nickds1]

Nitrogen or Argon... or really any heavier than air based gas.

Pure Nitrogen is about 3% lighter than air at STP; Argon is denser than air, but probably more expensive than Nitrogen.

Having said that, a quick squirt of N2 into the can and whip the lid on will work just fine - anything that is relatively non-reactive and displaces Oxygen is good.

In my old day job, we used oxygen depletion fire suppressant systems in data centres - the idea is that in the event of a fire to reduce the oxygen level to below 15% - this is a natural/non-invasive way of reducing fire spread - it also doesn't kill any humans in the room when it goes off! Normally we used argon/nitrogen and sometimes a bit of CO2. Previous systems used rapid displacement of oxygen with halons or similar - that removed all the oxygen from the space but any humans in there were in trouble - there were warning sirens to try to give you time to get out before the explosive discharge of the halon (or whatever). These older system were also dangerous in that they were so violent that they could displace (throw around) the very heavy supporting floor plates which could (and did) trash anything in their way, including servers and... humans... If you survived that, you then suffocated...

Nowadays, there are products like Novec 1230 which has almost zero environmental impact and are thus a good choice too.

 

[Gavlar]

thanks for the gas-related suggestions - I will investigate where to get such from economically - the wine-preserver type seems expensive so may try argon for welders, which seems way cheaper.

 

[Fergie 307]

Was going to say if you have a tig welder use the argon from that, dont know if they do the disposable ones in Argon, certainly do Argon Co2 mix, don't know if that would work.

 

[Rorschach]

What about R134a as found in air dusters? Cheap and readily available when the can is inverted it comes out as a liquid, very cold and dense so would sink into the can and stay there while you put the lid on.

 

[julianf]

I find it's like wrapping paint brushes in cling film...

...fine if you use them regularly. But the moment you take a break you end up with a hard lump!


I'd not considered the argon thing. My tank is down to a out 100bar at the moment, but that's still 300 ltrs of argon, and my polyx tin is a 750ml one.

The thing is, I never know when the time is when I won't be using it for a while!

(Which is exactly why the paint brushes in cling don't do so well either!)