AV Vallejo Model Air clogging

[CasualModel98]

I have been tolerating this problem for a while so looking to see if there is a fix. When spraying with AV Model Air out of the tube, I find the AB always clogging after a few minutes. It seems the paint dried in the AB.

 

Perhaps because I stay in Asia the warm weather causes the drying?

I tried adding AV's own thinner but that helped for a short while, but made the coat too thin.

 

Mixing AV with lacquer thinner makes it gum up immediately.

Mixing with ethyl alcohol gums it up immediately.

Mixing it with 30%IPA:water seems to leave small particles and gum up my AB within 5 mins as well. (It seems IPA only works on Tamiya acrylics and not AV paint. )

 

I am thinking of giving up on AV but I like the hard shell it leaves behind when dried, much more resistant to knocks and scratches compared to MrColor lacquer and Tamiya acrylics.

 

Anyone has the same problem and figured out a better solution than thinning with AV's own expensive thinner?

[Shin]

Not sure if I have the right answers for you, but definitely don't thin it with lacquer thinner or ipa, that will gunk it up (as you've seen). Both Model Color and Model Air will thin successfully with water though (if your tap water isn't pure you should try distilled water). 

[bhouse]

This could be caused by spraying at the wrong pressure. I find about 0.8-1bar works well with Vallejo Model Air - suitably thinned.

Adding some retarder may help - I use the Vallejo one. Although it's comparatively expensive, it is formulated to work with the paints themselves.

[bmwh548]

Vallejo is an actual waterbased acrylic so it won't respond well to alcohol or lacquer thinner. Use their own thinner and add retarder in the mix. Also you might want to try mixing them in a cup or something to watch for grit in the mix or anything that might clog up the nozzle. You didn't say anything about the airbrush but I personally avoid using anything smaller than 0.3 when it comes to acrylic paint (or more specifically non-lacquer). 

 

As an extra precaution put a few drops of thinner in the airbrush and blow it through before adding paint. That will get rid of any airbrush cleaner residue that might react with the paint.

[spruecutter96]

Hi. 

 

Do you clean your airbrush between every use? Do you take it apart and clean it?

 

Around about 90% of airbrush problems are caused by old, crusty paint clogging up the parts. If you are a little bit paranoid about cleaning it after every use, it should keep things moving along nicely for you. 

 

Hope this helps. 

 

Chris. 

 

PS: Also, try mixing your paint with acrylic "flow/ drying retarder" (that's what it's called in the UK....it could have another name in other territories. I bought mine in an artists-supply shop, but it's readily available on E-Bay and Amazon. This stuff stops the paint from drying too quickly (takes several minutes, as opposed to seconds). 

Edited August 13, 2019 by spruecutter96
Adding some info.

[Evil_Toast_RSA]

Try using the Flow Improver ( 71.261) and use the Airbrush Cleaner (71.099) instead of the thinners, live in a humid climate myself and that reduced my tip drying problems quite substantially. 

[LotusArenco]

On 8/13/2019 at 3:00 PM, Evil_Toast_RSA said:

Try using the Flow Improver

Yep, try that if you’re not already.

 

Vallejo has two additives to thin their acrylics for airbrushing, ‘Airbrush Thinner’ and ‘Airbrush Flow Improver’. Since moving over to using the ‘Flow Improver’ I suffer from hardly any tip block and seems to be quite an improvement over the ‘Thinner’.

 

Mart

[Crankycraftsman]

On 8/14/2019 at 12:50 PM, LotusArenco said:

Yep, try that if you’re not already.

 

Vallejo has two additives to thin their acrylics for airbrushing, ‘Airbrush Thinner’ and ‘Airbrush Flow Improver’. Since moving over to using the ‘Flow Improver’ I suffer from hardly any tip block and seems to be quite an improvement over the ‘Thinner’.

 

Mart

According to Vallejo, your supposed to use the thinner with only a drop of the flow improver in your paint cup. Are you saying that you are using only the flow improver to thin your paint?

[LotusArenco]

On 8/22/2019 at 6:38 PM, Crankycraftsman said:

Are you saying that you are using only the flow improver to thin your paint?

Yes.

Recently I’ve only been using my airbrush to paint small wargame miniatures, and I picked up that tip from watching numerous figure painting youtube videos. They seemed to be achieving a much better result in just using the flow improver so I thought I’d give it a go.

So far I’ve used it to thin Vallejo model color, model air, game color, Liquitex ink, the newer Humbrol acrylic and Games Workshop acrylics. You do still occasionally get some tip-dry, but nowhere near as much as I used to.

 

Mart

[Ratch]

Using flow improver to thin the paint seems excessive to me. I can usually spray VMA without thinning (or clogging for that matter), but yesterday had to thin the Silver (an old bottle) that seemed to have thickened. Putting a finger over the nozzle to create blow-back helped to clear the clogging and restore paint flow. When adding flow improver it has literally been a drop or two to the airbrush cup.

[Basuroy]

Vallejo is an abomination of a paint and avoid it like plague . I have around 10-12 bottles , purchased in one go and still regretted. All model air series.

Some of them are already water thin in bottle , some thick as goo . Some of them can be thinned with IPA while some only with water. Each paint require different thinning medium and thinning ratio.

NONE of them adhere firmly to the surface and NONE of them are suitable for fine detail work using airbrush . I also get the maximum instance of tip dry with them ( inspite of using golden airbrush medium which has retarder) and I stay in Kolkata with 70-90% humidity. They also take almost twice as much time as Tamiya or Gunze to reach same opacity/coverage . 

The only saving grace is they go on nicely with the brush which is how I use them .

Only paint from vallejo that I will vote for is their Metal color range . As far as acrylics go , they are the best NMF paint out there.

Edited August 26, 2019 by Basuroy

[Ratch]

I have over 100 Vallejo paints and swear by them.

[CasualModel98]

On 8/26/2019 at 6:48 PM, Basuroy said:

Vallejo is an abomination of a paint and avoid it like plague . I have around 10-12 bottles , purchased in one go and still regretted. All model air series.

Some of them are already water thin in bottle , some thick as goo . Some of them can be thinned with IPA while some only with water. Each paint require different thinning medium and thinning ratio.

NONE of them adhere firmly to the surface and NONE of them are suitable for fine detail work using airbrush . I also get the maximum instance of tip dry with them ( inspite of using golden airbrush medium which has retarder) and I stay in Kolkata with 70-90% humidity. They also take almost twice as much time as Tamiya or Gunze to reach same opacity/coverage . 

The only saving grace is they go on nicely with the brush which is how I use them .

Only paint from vallejo that I will vote for is their Metal color range . As far as acrylics go , they are the best NMF paint out there.

I made a post about this in another thread. I found that Butyl Cellosolve is the main ingredient in AV thinner. Smells the same and works well when added to water to thin AV or just to clean the airbrush. Funnily I bought it on Amazon India. One bottle of 500ml was INR250 or about 2-3 pounds? 

 

So if you are looking for a cheaper thinner source for you AV paints, try this. Look at my thread.

 

[Basuroy]

3 hours ago, CasualModel98 said:

I made a post about this in another thread. I found that Butyl Cellosolve is the main ingredient in AV thinner. Smells the same and works well when added to water to thin AV or just to clean the airbrush. Funnily I bought it on Amazon India. One bottle of 500ml was INR250 or about 2-3 pounds? 

 

So if you are looking for a cheaper thinner source for you AV paints, try this. Look at my thread.

 

I can't thank you enough for this tip. Yesterday , I found that the thinner medium in 3 (out of 5) of my Metal color bottles have simply evaporated . It is a thick goo inside and hopefully will salvage them for me . Vallejo and revell - I don't know if it is their bottle design or the type of solvent they used but they have alarmingly short shelf life. Virtually every single vallejo paint I have (2-3 years old) is thick now . Same with revell aqua. 

 

[CasualModel98]

On 9/6/2019 at 5:40 PM, Basuroy said:

I can't thank you enough for this tip. Yesterday , I found that the thinner medium in 3 (out of 5) of my Metal color bottles have simply evaporated . It is a thick goo inside and hopefully will salvage them for me . Vallejo and revell - I don't know if it is their bottle design or the type of solvent they used but they have alarmingly short shelf life. Virtually every single vallejo paint I have (2-3 years old) is thick now . Same with revell aqua. 

 

Mix it with distilled water (not mineral and not drinking water) at a 30:70 or 50:50 ratio. I add IPA to it but I think it is not needed. 

[CasualModel98]

One more point, Butyl Cellosolve evaporation rate is 0.08 compared with water at 0.3. So it dries slower than water. If you use too high a concentration, it takes a long time to dry.

[Basuroy]

13 hours ago, CasualModel98 said:

One more point, Butyl Cellosolve evaporation rate is 0.08 compared with water at 0.3. So it dries slower than water. If you use too high a concentration, it takes a long time to dry.

These are all very informative tips - I will go for the 30:70 ratio since humidity is high here . 

[Ratch]

Just had to share this

DSC_0001 by Richard Linnell, on Flickr

[Baran İşmen]

* Don't exceed the 20-25 Psi,

* Thin the paint in a 1:2 (thinner:paint) or 1:1 ratio with their own thinner (don't think about the coverage, you can make a second pass and it'll throughly cover all)

* Do NOT use IPA for thinning, it's only for cleaning. As it makes the paint lumpy (which is the main reason not to be used for thinning), you have to clean the particles out of the airbrush cup by a towel or something, otherwise the remaining lumpy paint parts will clog the nozzle.

* You can add just 1 or 2 drops of Glycerol to their own thinner which will delay the drying time both over model and in the airbrush cup. So be careful with that.

* As CasualModel98 suggested, you can make your own thinner with Butyl Glycol and Water mix. I'll get a liter bottle and will share the results as well, but it's the real deal.

 

Happy modeling