"Why would brush on varnish frost/crack?" Topic

Age of varnish?

The brush on varnish I'm referring to is the dropper bottle that comes with Vallejo's game color suitcase set.

I used it on a few plastic minis about a month ago and the finish was perfect and matte.

Then I went to use it again recently on a larger group of painted plastics. The varnish settled in some areas like creases of clothing, folds in flags, etc. When it dried it clouded and cracked in some areas, like cracked mud weather effects.

But on most areas of most of the minis. the finish was perfectly fine.

So would it be just the age? The Vallejo set is from 2012 but all the paints are perfectly good, I assumed being in dropper bottles the varnish would be good too. Maybe six years is past a brush on varnish's shelf life?

Can't be atmosphere, I varnished in a moderately heated, dry painting space, low 70s interior temp.

Just as an aside, I had been using Army Painter brush on matte varnish before I decided to try the Vallejo out. The Army Painter is flawless, it's by far the cleanest, flattest finish I've ever seen in a brush-on varnish. It also happened to be newer, bought in 2016/2017.

Could be incompatibility with the paint used?

Super glue can fog up varnish.

I've read that high humidity can cause fogging of varnishes, though I've never experienced this. Cracking could be caused by the surface of the varnish curing more quickly than underlying layers. I note that you described the varnish as settling in creases which probably means that it was applied a little too heavily, creating the problem described.

Agreed with the above re heavy application.

With Vallejo you never want to shake the dropper bottle. Roll it with your hand on a flat surface to mix it. If you shake it – esp. the gloss and or flat the contents will not mix correctly.

I know this sounds strange: several years ago I was at an IPMS seminar put on by Vallejo and sitting in the front row. I noticed that the presenter was constantly rolling the colors he was using and not shaking the bottles.

I asked why: he told me what I've written above. From that point on I have never had a problem with Vallejo separating or drying uneven as described above.

@Joes Shop: Thanks for the tip.

Some great info, thanks!

But I have to ask…why on earth then does it say right on Vallejo's varnish "Shake well"?!?!?!?

Army Painters varnish is supposed to be shaken and works perfectly. Is Vallejo's formula like different?

Also, does that rolling also apply to their paints???

Shaking paints to agitate them along with a ball bearing thrown in, certainly isn't generally something considered bad! Shaking and stirring…

I've stirred Vallejo paints that had separated, and have shaken them as well. No problem with the paints whatsoever!

Maybe it's just their varnish? Most, if not all brush-on varnishes I've seen all say to shake them. I do not understand for the life of me why they would put the very instruction on the bottle that would make the varnish malfunction?!?!?

OSLIC: happy to help.

From the Vallejo FAQ:

"Shaking the paint creates foam- the oxygen in the bottle (between cap and paint) mixes with the paint, and expands the volume, so that it bubbles over when you open the bottle. The correct way of mixing the product is rolling the bottle, between your hands, or on the table. But the foam will subside after a few minutes, and no harm is done."

B: I know the bottles say to shake – and I asked about that too. I honestly don't remember the exact answer but it had something to do with the wording required by the US on imported hobby paint.

B: when I first tried Vallejo Flat/Gloss (airbrush) I had the exact same effect you describe above.

After I switched to rolling – no issues.

I don't know 'why' rolling works – but I can tell you I've never had any problems since and they are now my go to sealers.

Wow, thanks this is really interesting…!

I will roll Vallejo paint bottles from now on and see what it does.

But, just throwing this out there. The Army Painter anti-shine is quite simply a superior product to Vallejo in every way. Army Painter seems like a true hobby varnish, Vallejo feels more like it's an artist varnish. I understand completely about not using too thick of a coat when brushing it on. But the Army Painter is 100% user friendly. Even if you accidentally have an area where it might collect a bit, it still evens out and dries totally clear. Whether it's actually meant to be shaken or not, Army Painter says to and I did and it comes out perfect.

Given that I only own one bottle of the Vallejo varnish, I'm it's not worth all the fiddle-faddling and worry and babysitting it seems to need…..will just stick with Army Painter.

I appreciate the in-depth info. provided but personally I hate hobby products that have an "asterisk" list of secrets that require you to dance around it to make it do what it's supposed to do!

B: understood.

Don't know if you got an answer to your problem, but I'm going to change my way of dealing with my Vallejo paints from now on!

I would try rolling my varnish, but it's in a square bottle !