Humbrol spray varnish problem

[Weaver]

Wonder if anybody else has had the same problem:

Three times now, I've bought a rattle can of Humbrol Matt Varnish. It worked fine the first time, and I carefully cleared the nozzle by spraying inverted for a few seconds when I'd finished. A few months later, I come to use it again, and it won't spray, apparently because there's no pressure in the can. The nozzle ISN'T blocked and there IS varnish in the can, just either no propellant or the propellant isn't working. Warming it in a bowl of warm water and shaking it for ages gets it to spray for about 10 seconds but then it's gone again.

The cans live in the cellar, which is cool, but not really cold as such, and anyway, paint cans kept right next to them work fine.

Any bright ideas?

[sequoiaranger]

Sounds like there is no "operator error", just defective cans of matt varnish. Can you maybe write Humbrol (whoever "owns" Humbrol now) and somehow get a "coupon" for more cans? If it is a production-wide defect, maybe Humbrol knows about it and might offer some sort of compensation. Worth a try.

[deathjester]

Perhaps the best move would be a cheap airbrush/compressor set, and lay in a stock of water based varnish.  That should keep your costs down in the long run, and you can strip down the airbrush for cleaning

[Mike Wren]

I've had the same problem with them, ended up throwing some cans away as there's seemingly no pressure in them. sometimes just leaving one a few days then coming back to it makes them spring back into life... other times not!

it's a shame as I think they give a nice flat finish

[Weaver]

Thanks All.

I've just bought another can of the stuff from a different shop, to see if it's a "batch" issue. Fingers crossed.........

[Weaver]

Well the new can has just done exactly the same thing.....

The nozzle DEFINATELY isn't blocked because you can spray airbrush cleaner through it.

The can (and the other duff cans) still has pressure, because if you put a different design of nozzle on it, it sprays. It won't spray with ANY nozzle of the same design as the original though, even if it's come from a paint, rather than varnish, can.

The problem MUST therefore be some interaction between the nozzle and the can. My best guess is this: all Humbrol spray cans are the same design, having a rubber ring inside the neck of the can, through which the nozzle's tube must pass, so I think this ring is affected by some component of the varnish (but not the paint) which causes it to swell so that the nozzle tube won't go through it. This is confirmed by the fact that on affected cans, the nozzle seems to sit higher than on paint cans and feels wobbly, and also, the nozzle tubes of all affected cans have a black deposit on them, like dissolved rubber, which all the paint cans don't.

I'm going to write to Humbrol about it.

[NARSES2]

I'd charge them for that "design testing" if I was you. Interested to hear what they say

[ChernayaAkula]

Did something ever come out of this?

Asking because the LHS wants to reduce their plastic model stuff (they're originally a model railroad shop) and they have the Humbrol cans on sale for just 3 EUR each. Already got a can of gloss black (didn't use it yet, though), but wondered about the varnishes.

[beowulf]

ive never had this prob, i must say.....i use allssorts of humbrol rattlecans 

[Geoff]

ive never had this prob, i must say.....i use allssorts of humbrol rattlecans 

Nor me - I only use the varnish though.

[Weaver]

Did something ever come out of this?

Sorry, only just seen this.

I don't think I ever got a reply from them. I've used them sparingly since, and they've been okay. Maybe a dodgy batch in the factory?