airbrush questions

[zemjw]

Never had a problem with Vallejo paints clagging up with Tamiya thinner.

Back when I was switching from enamels and learning to use acrylics I tried thinning vallejo with tamiya thinner. The result was strands of string that were completely unusable. This was brush, rather than airbrush, but there was definitely a serious chemical reaction taking place.

[pauld]

Anyway, when I turn on my airbrush the air constantly flows out the front? Is this the way it is meant to work? paint only comes when I pull back on the lever but I guess I always had the impression that air only flowed when the lever was pulled.
Thanks and I only ask as I think the answer may be too simple even for beginner tutorials on airbrushes
Also, how much do you usually thin the paint. I've seen 20% thinner, 50%, 25% with regular paints not airbrush specific paints. Thanks

I bought one very similar to the one in your link and it had an extra adapter to make it a double action - push finger control down to release air and pull finger control back to release paint.

When the pen is screwed direct to the compressor base it is single action and adding the little chromed adaptor piece between the pen and the base compressor turns it into a dual action.

I'm actually rather pleased with mine for priming and base coating and have not tried anything clever like layering up a bigger model yet.

[Blackwolf]

Never had a problem with Vallejo paints clagging up with Tamiya thinner.

Intriguing,very lucky; or the chemical makeup is different to the thinner supplied to Oz. Tamiya paint isn’t a true acrylic,it’s sort of hybrid between lacquer and acrylic,so is a bit ‘hotter’ than Vallejo for example.

[2010sunburst]

That looks like a double action brush Beefy.  I would explore Paul D’s ideas as they sound feasible.
Tamiya is acrylic, by the way Blackwolf.  It is just that it’s acrylic binder is formulated to use alcohol as a solvent rather than water. 
When I’ve used Tamiya thinner with Vallejo (or any other acrylic using water as a  solvent that I’ve tried) the paint turns into cottage cheese.  It’s horrible to clean out of the airbrush because the binder structure just completely breaks down. 

[Blackwolf]

  Yep,that’s what I said here and previously. It’s an acrylic just a different makeup to Vallejo et cetera, I would mix them with say AK or Scale 75,that way leads to madness.

[katie]

"Anyway, when I turn on my airbrush the air constantly flows out the front? Is this the way it is meant to work? paint only comes when I pull back on the lever but I guess I always had the impression that air only flowed when the lever was pulled."

Yes. The idea is that you press to turn the air on and then gently throttle the paint into the airstream using the fine control on the lever. Any empty airflow also helps dry the paint on the model as well. Start the air with it pointing slightly away from the model so if it burps paint it won't go on your model. Then you can point at the model and start the paint flow. Aim to underpaint rather than over -- you can always give things a second dose.

[Captain Harlock]

A double action airbrush, works by pressing down the trigger for air and pull back for paint. If there is a constant flow of air even when you are not pressing the trigger sown, that means that either the nozzle is destroyed, or the needle is not properly sitted all the way to the front. Just push it gently until you feel that it made contact and then try again.
Generally these cheap airbrushes are completely garbage and these little compressors cannot provide stable and continuous flow of air. Especially when you are a novice, you have to fight inexperience along with a faulty tool. All these cheap airbrushes are usually copies of Olympos/Iwata but without the precission machining and they try to compensate with rubber o-rings. Thats why even the few that actually work, in the future will require repairs/improvements.

Right now the best airbrush for its money imo are the Mr Hobby Creos ones. They are basically as good as Iwatas but at a fraction of  the price. I think they are made at the very same factory in Japan. Probably their price will go up in the future.

Air-compressors are an issue. Some of them can be annoyingly loud especially if you have late night hobby hours. The silent ones are quite expensive. Personally I went full diy and made a silent compressor, using a refrigerator motor. I payed around 100 euros in materials but I got something that in the market would go for over 500. It has a big tank that allows 45 min of continuous work (Im spraying at 14 psi mostly) and when it has to refil the whole think sounds like... a refrigerator.

[2010sunburst]

Not sure that’s correct Capn……if the nozzle or needle were not seated properly or damaged Beefy would be getting paint as well as air through the brush.  If Beefy is getting air without doing anything to the trigger then either the air valve beneath the trigger is being held open or it’s damaged, as described by Paul D. 
I also think you are perhaps being a little unfair on the clone brushes.  I know many modellers that are perfectly happy with a clone brush and an AS 186 compressor.  Those guys produce complex Camo patterns on tanks and aircraft with them. 
I personally am perfectly happy with my mid price Iwatta and smart jet pro compressor, but that set up is overkill if all you want to do is lay down primer, produce Zenitel highlights and varnish figures. 

[Captain Harlock]

Not sure that’s correct Capn……if the nozzle or needle were not seated properly or damaged Beefy would be getting paint as well as air through the brush.  If Beefy is getting air without doing anything to the trigger then either the air valve beneath the trigger is being held open or it’s damaged, as described by Paul D. 
I also think you are perhaps being a little unfair on the clone brushes.  I know many modellers that are perfectly happy with a clone brush and an AS 186 compressor.  Those guys produce complex Camo patterns on tanks and aircraft with them. 
I personally am perfectly happy with my mid price Iwatta and smart jet pro compressor, but that set up is overkill if all you want to do is lay down primer, produce Zenitel highlights and varnish figures.

You are right! I assumed that he didnt add fluid in the cup and he got just air from the front.
Dont get me wrong, Im the last man who will scorn cheap solutions because they lack a fancy logo. Im all for diy solutions and cheap alternatives, thats why I would never pay 300-500 euros for an italian silent compressor that is basically a freezer motor with a new coat of paint on. But when it comes to airbrushes most of the times you get what you pay for. There are cheepos that run just fine. The problem is that due to the lack of quality control getting a good one is a matter of luck. You can sort of improve their performance with afew hacks like removing the rubber o-ring and sealing the nozzle with beeswax, or polishing the needle, but can a novice do this?
There is always the solution of buying one second hand. I have an iwata Eclipse and an iwata HPC+. I needed an airbrush to spray  primers and thicker paints without worrying too much. I got a Revell Vario, which was a rebranded Thayer and Chandler Vega 2000, actually this kit https://www.midwestairbrush.com/ve20deaiset.html here for 35 euros. This airbrush can spay even concrete . A chinese clone would cost around 25 euros and now EU tries to penalize purchases from China and you have to pay VAT and import taxes.

Another solution is to go for a chinese knock off that is carrying the brand of an established company. For example AK offers some models that are clearly HP clones. They go about 40+ euros but at least you can hope that they will have some kind of quality control and you can always return a broken one. https://ak-interactive.com/product/ak-airbrush-basic-line-0-3/

[Blackwolf]

Hmmm . The cheap airbrush question. I started out with a Pasche bottom feed,basically learn’t on it,then went to a Aztec,which in hindsight was a retrograde step. Now I pretty much always use Harder and Steinbeck (I’ve got four of them),the interchangeability of the  parts is brilliant,and I can get all the parts in Oz. And they’re simple to take apart and clean. I do have other ‘brushes,Iwata,Badger et cetera,it’s the H&S that’s always on the compressor though

[2010sunburst]

Hi Capn.  I do know exactly what you mean about cheap brushes. They can work well straight out of the package, and can be tweaked and improved if you have the knowledge.  As to compressors, I know they are all repurposed fridge/freezer technology (as are domestic heat pumps) but if you buy from a decent manufacturer you buy quality control again.  DIY is an option if you know what you’re doing, but the stored energy in compressed air makes it a dodgy area for the hamfisted DIY buff.  I’ve seen the aftermath of a gas cylinder incident…..the cylinder was dropped, the PRV end had been badly fitted and snapped off on impact,  and the cylinder went through two brick walls like a torpedo before it stopped!  Thankfully no one got hurt.
Completely agree ref. the Aztec, Blackwolf.  I got one as my first “proper” airbrush about twenty years ago and struggled with it for quite a few years afterwards.  I always thought it was me at fault 
When I got the Iwatta it was like turning a light on.  The issues I was getting were that the parts in the Aztec were cheap and badly fitting (only one of the six nozzles I had really worked properly) and it was incredibly air hungry…..the AS 186 compressor I had simply couldn’t keep up.  I still have it, and even my smart jet can’t really keep up with it…..there are no air leaks, it just needs far too much air to drive it. 
I hot rodded my Iwatta, by the way, by fitting a fast flush handle.  I can carry out a full strip down of the paint path for cleaning in about fifteen seconds…..it’s also a side feed so the whole paint path is more accessible for cleaning.  I’ve had it for about ten years, and can’t really see me wanting anything else.

[Harry Faversham]

There's a beginner's guide to airbrushing in this month's Wargames Illustrated Magazine.

[beefcake]

Thanks. Might have to check that out