Starting to airbrush, having problems

[Guest]

So I bought a Badger TC910 (compressor and tank) and a Badger Krome. I finally started to use it and I keep having problems. The airbrush constantly clogs using Badger Stynylrez primer and I havent started any other paints.

 

I am running at 25 psi, and just the primer nothing else. I am using the default needle too (I think it's the larger one). I am letting the compressor finish working up after turning on also as the instructions say. So what am I doing wrong?

 

Also while I am on the subject. What thinner do you guys use. What is your ratio of GW, air and/or normal, to thinner do you use.

 

Thanks for the help.

Edited November 24, 2017 by Caldersson

[Dantay VI]

Is tat 25 psi before you start spraying or while you are spraying?

[Guest]

While spraying.

[Dantay VI]

What about flow improver? Could be the paint is drying on the tip of the needle. The flow improver will slow the drying time of the paint down, may stop the clogging on your needle

[Guest]

Isn't flow improver the same as thinner? I have read to never to thin primer as they will crack as the self leveling won't work and it makes the primer be ineffective.

[Dantay VI]

No thinners and flow improvers are different.

 

Thinners reduce the strength of the paint by making them more liquid. The thinner your paint the faster it dries, or so I am led to believe.

 

The flow improver acts as a retardant, so it stops the paint from drying so quickly, it also thins the paint slightly too.

[Arkhanist]

You want to be using 0.3mm or bigger for stnlyrez, and 25-30 psi. So first you definitely want to check you're using the larger 0.33 mm needle with the krome - the 0.21mm one will struggle.

 

It should spray neat that way, but you will have quite bad tip-dry, which I think is your problem. Literally, paint dries on the tip of the needle and inside the nozzle, blocking the flow. This is the bane of spraying acrylics, and something you will encounter a lot.

 

The simplest 'fix' is to use a q-tip wetted with cleaner and wipe off the needle tip every few minutes or when it starts to struggle - be a bit careful, the needle tip is sharp! If you 'soak' the tip in cleaner, and just pull the needle back and forth without any air (ie. pull back the trigger without pressing), it will get a bit of cleaner inside the nozzle and help remove any dry paint there.

 

Stynlrez is pretty thick though, and dries very quickly so is particularly prone to tip dry.

 

Paint is made up of water, acrylic binder and pigment. Thinner (or reducer) is adding a little water/acrylic mix which is basically transparent paint. This shouldn't generally affect the grip or drying of the final finish significantly (unless you use a lot!) but can affect the coverage, i.e. it doesn't have as much pigment, so you may need an extra thin layer. This is normally used when the paint is too viscous, and you want to make it more watery so it will spray with your nozzle size (the smaller the nozzle, the more dilute the paint needs to be for a given pressure). Water alone can also dilute the grip and nature of the paint, so is not great for primer, but can be used (up to a point) for thinning layer paints. This is usually used for, for example, diluting brush paints for use in the airbrush - airbrush-ready paints are already thinned, though some (such as citadel air) benefit from a little extra thinning.

 

In this case though, it's not that the paint won't go through the airbrush at all because it's too thick (assuming you're not using the 0.21 mm nozzle). I think that it's drying too fast.

 

This is where a drying retarder (also called slow dry) comes in useful. It's an additive that literally slows down how quickly acrylic dries. You only want a little, a drop or two in the cup, but it slows down how quickly the paint chemically bonds. Which works both on the tip, and for the model. For the model, it's exposed to so much air that it makes little difference, but it does stop it drying on the airbrush tip so quickly. Using a lot can cause problems with the finish or even stop the paint drying properly at all, so definitely use in limited quantity. Some airbrush thinners (such as vallejo) do already include a little drying retarder as well.

 

The final option is flow improver. This is another additive, that reduces the surface tension of the water which helps the paint get through the nozzle and spray more smoothly. It also help slowing the paint dry a bit. Again, it's something you only want to use a drop or two of per cup. It's hard to describe, but I find it just makes paint 'behave', so I use it quite a bit with brush painting too.

 

Personally, I almost always now add a drop of flow improver when airbrushing, regardless - it has significantly helped me with tip dry and even flow for trickier paints. With thicker paints or just if the paint feels a bit sticky I also use airbrush thinner to get them down to semi-skimmed milk viscosity or so. If I'm particularly suffering from tip-dry or clogging, I'll also add a little retarder as well.

 

I use vallejo flow improver and airbrush thinner - they work fine with vallejo and citadel paint - and liquitex slow dri as a drying retarder simply as that what was available at my local art shop. I do try and avoid diluting primer much, or at all, and just stick to the flow improver.

Edited November 25, 2017 by Arkhanist

[Guest]

So I took it all apart found out that it came with a .21 needle installed, swapped it out and got a qtip with cleaner nearby to keep the tip cleaned. Thing ran like a charm and was actually a lot more painted than I expected. Going to keep trying thing until I get it down. One model had a but too much primer and it ran a little.

 

Thanks allot for the help!