Paint tins popping open: how to fix it?

[Richard502]

Whats the cause, and what's the fix?

TIA, Richard

[dogsbody]

Okay, what paint tins? What brand of paint? Metal tinlets or plastic pots?

 

Inquiring minds need to know!

 

 

 

Chris

[Head in the clouds.]

19 minutes ago, Richard502 said:

Whats the cause, and what's the fix?

Never come across it myself but I am migrating away from tins (Humbrol/Hannants own, cannot remember brand name) after a while they all turn to jelly no matter what I do.

 

How do you store your tins, not as strange a question as you may think as I have heard of some standing them upside down.

[Black Knight]

Its the solvent being released as a gas and building up pressure.

It happens to mine sometimes.

Sometimes this works, blow across the top of the open tin as you press the lid down. The blowing across causes a slight vacuum and reduces the solvent gas pressure. Sometimes it works

[Graham Boak]

It was said to be exploding tin cans, particularly metallics, that lead to the band on carriage of paint by air and thus Royal Mail and other carriers.  However in 65 years modelling I have never encountered this, but I have had screw top jars become unusable, and will stick to the tins.

[Black Knight]

Its usually tins that have been opened and stirred very well, used, then when you try to push the lid back on it just keeps popping up at one side. I usually use only Humbrol paints so its with those I get this.

[rayprit]

Never happened to me in 60 years...……..perhaps its something to do with the new formulae ………..are they new paints?

[Graham Boak]

Sounds more as though you aren't cleaning the rim and lid sufficiently, so that it just isn't fitting.  As you describe it there isn't enough time for any fumes to build up pressure. Poorly fitting lids would also explain your problems with paints caking.  I suspect we've all suffered from that problem.

[Black Knight]

New tins, usually new/recent formula

[Circloy]

With older well used tins it's usually a build up of dried paint, with new tins I've put it down to larger lids /smaller openings.

 

In the factory lids are fitted by machine so will be applying some pressure, I've taken to tapping lightly with a small hammer.

 

[John]

I've only ever had this with Humbrol from late Humbrol ownership era, and only a couple of tins. 

I think they might have been slightly over-filled, leading to a built up of pressure when the lid is pressed down. 

 

John 

[Space Ranger]

2 hours ago, rayprit said:

Never happened to me in 60 years...……..perhaps its something to do with the new formulae ………..are they new paints?

Same here.

[rayprit]

1 hour ago, John said:

I think they might have been slightly over-filled, leading to a built up of pressure when the lid is pressed down

I have noted in the past that the NEW paint is more of a sludge than a liquid and when I open the lid there is no room inside for air...they fill them well above the rim...……..in fact when taking the lid from the tin the sludge is like treacle on the lid.....no room for air in there at all - I binned this paint as there is not even room to stir it in the pot......need a knife to get contents out of tin.

 

I have found as stupid as I am, sometime I do not push the lid on as tight as it could be resulting in the contents inside the tin to go solid...…..I always physically brush thinners on the base of the lid and clean whole lid spotless with rag before re-applying to tin, always works, and once closed always shake tin to seal any gaps that may still be around base of lid