Use, cleaning and thinning – Acrylics

Max - happy painting!!! hope you enjoy!!! wow that was wierd, maybe that was a reutnr and someone tightened the head down with those proverbial pliers??

Good luck to you!!! Glad to hear it's solved!!! I was getting to wits end on how to help you!

tho9900,

Tried everything and no luck. So I boxed the airbrush and took it back to the retailer and exchanged it.

Annnnnd…it works – no pulsing or bubbles.



Phew, I was getting a bit worried I’d never get it sorted.

Big thanks to you and everyone who helped.

Max

QUOTE: Originally posted by tho9900 Max - ok let's try to get to the bottom of this. your airbrush is new so the teflon washer probably isn't the culprit. Your needle/nozzle combo is new at least for the medium so it's probably not that... Your compressor appears to have a tank already so that should dampen any pulsating from there... Ok - when you put the needle in gently push it all the way forward until it is tight in the tip (i.e. can go no further) then tighten down the knob at the back of the brush that holds the needle in. Check your spray bottle to make sure the tiny hole that allows air in the bottle is clean and clear... if you don't see the hole look closer, you can poke the dried paint out with a toothpick or straight pin. Make sure the head is screwed hand tight, turn it as tight as you can with your fingers but don't try to force it too tight... and no pliers Disconnect the hose from your airbrush and turn the pressure up gradually, see if the air coming from the hose pulses. If not we can totally rule out the compressor. Hopefully we can come to something with all this! Good luck!!

tho9900,

Ah, I’ve just read MC’s post and something occurred to me. I’ve just taken the head assy off and there seems to be a slight “raise” between the air hole in the airbrush body and the thread for the head assy. Could it be that this is letting air past or damaging the Teflon washer? This would explain why the med needle/nozzle worked the first time but didn’t work after I swapped it around a couple of times.

Will try as you suggest and report back tomorrow (it’s 1:00AM here)

Cheers,

Max

Max - ok let's try to get to the bottom of this.

your airbrush is new so the teflon washer probably isn't the culprit.

Your needle/nozzle combo is new at least for the medium so it's probably not that...

Your compressor appears to have a tank already so that should dampen any pulsating from there...

Ok - when you put the needle in gently push it all the way forward until it is tight in the tip (i.e. can go no further) then tighten down the knob at the back of the brush that holds the needle in.

Check your spray bottle to make sure the tiny hole that allows air in the bottle is clean and clear... if you don't see the hole look closer, you can poke the dried paint out with a toothpick or straight pin.

Make sure the head is screwed hand tight, turn it as tight as you can with your fingers but don't try to force it too tight... and no pliers

Disconnect the hose from your airbrush and turn the pressure up gradually, see if the air coming from the hose pulses. If not we can totally rule out the compressor.

Hopefully we can come to something with all this!

Good luck!!

QUOTE: Originally posted by tho9900 Max - a PE Bender is a jig to place photoetched parts in to bend them properly to fit in the kit... once you do Photoetched parts you'll wish you had one!!! hmm... and what kind of compressor do you have? sometimes the compressor can cause that.... you might want to take the needle out, make sure it is clean, remove the tip and head assembly and soak them in lacquer thinner for about an hour or so then reassemble and try again... don't think it is that since the fine did it and you haven't used it before... ifyou have a diaphragm compressor they can do that... only fix I know of is some sort of reservoir like a small air tank to absorb the pulses...

tho9900,

The compressor:



Capacity - 30 lt/min / 1.06Cfm Pressure - 8Bar / 116psi Motor - 200W / 0.25Hp Voltage - 230V Tank (L) - 9

I’m fairy sure that the air supply is not the problem as it doesn’t start to pulse until the trigger is pulled back the water starts to flow. Plus, of course, the bubbling back into the bottle, which doesn’t sound right.

I’m also fairly sure there is no blockage (and, of course, I haven’t yet put any paint through the med nozzle/needle and the symptoms are the same with either set).

Hmmm…could it be the way I changed the needle/nozzles?

I set it up so that there is a slight spring pressure to seat the needle. Is this right? Is the needle supposed to seat “floating” with no spring pressure. Have I damaged the nozzles?

Marv

Max - a PE Bender is a jig to place photoetched parts in to bend them properly to fit in the kit... once you do Photoetched parts you'll wish you had one!!!

hmm... and what kind of compressor do you have? sometimes the compressor can cause that.... you might want to take the needle out, make sure it is clean, remove the tip and head assembly and soak them in lacquer thinner for about an hour or so then reassemble and try again... don't think it is that since the fine did it and you haven't used it before... ifyou have a diaphragm compressor they can do that... only fix I know of is some sort of reservoir like a small air tank to absorb the pulses...

tho9900,

What is a PE bender?

My model equipment now consists of a jig borer, TIG welder, Harrison lathe, box folder, 3’ metal rollers, various drills etc and now a compressor and airbrush. All I need is a workshop big enough to put them all in

PS the airbrush is now ‘pulsing’ with the medium jet/nozzle

Max

Max - sometimes you wont have the leak around the tip, or at least when it has happened to me I haven't noticed one.

Same for me though, Since the late 80's during my last modeling life I wanted an airbrush, I did get a BAdger 350 (limited capability for 1/72 though) and loved it. When I got back into this about 1.25 yrs ago I went through several cheapie airbrushes thinking the real thing wouls set me back a bunch.... I got on here found out I could have bought a good brush for what I paid for the old ones and now am working on my third 'good' airbrush... Now I can start looking for other toys to buy like PE benders and the like!

Thanks tho9900,

I’ve wanted an airbrush for longer than I can remember (about 20 years - LOL), and now I’ve got one

I didn’t notice an air leak around the nozzle assembly but I’ll try it again with some liquid soap around the joints. This should show any leak up.

MaxH

QUOTE: Originally posted by Spitfire 321 I too am starting out on airbrushing after many years of using brushes. I have a load of Humbrol acrylic paints and (although the lable gives no clues) I`m guessing that they are for the model maker rather than the artist. Does anyone know if this is true please?

Spitfire, I apologize but I thought I had replied to this last night... yes Humbrol is modeling paint. Quite a few people use it. You should get good results with it!

Max - I've never had the pulsing problem so can't help you with that one, maybe Scott (Music City) can give you more on that. The bubbling in the bottle I have had, once it was the head was not tightened down well... I got a piece of rubber for better grip and tightened it a bit more and it was fine. I have also had it with paint blocking the tip but if this is a new airbrush it wouldn't be that...

Main reason I replied is to congratulate you on diving right in with your airbrush. You should see good results very fast if you keep at it like you are.. (trying different things, getting the feel of it etc...) Good luck to you and I can't wait to see pics of your first model airbrushed!!!

Usually a pulsation in those brushes is caused by that Teflon washer between the head and body not sealing properly. They tend to get flat over time, and I always loosen my head assembly before I store mine. Could be that yours is just marginally too flat or the fine head might not have been tightened enough to give a good seal. If not that I'm not real sure.

In the meantime I swapped back to the fine needle/nozzle and tried some straight acrylic ink. The result was very odd. The gun seemed to be ‘pulsing’ i.e. intermittent paint delivery. I washed it out and tried it with water and three things became apparent: the spray pulsed at all trigger positions, the water was yo-yoing up and down the feed pipe, and the bottle was bubbling up when the trigger was on-air but off paint.

I tried it at various pressure settings (20-35 PSI) but still the same. I then swapped back to the medium needle/nozzle and it worked fine (still using water).

Hmm, can’t see any blockage in the nozzle assembly. Can’t see anything missing (sealing washer was in place etc). The needle seems to be seating correctly and it isn’t bent.

Why would it work ok with the med needle/nozzle but not the fine? As I was testing with water it can’t be a thinning issue???

MaxH

It certainly shouldn't hurt a 150, just blow some laquer thinner through it when you are done (insure you have plenty of ventilation!) and that will get rid of just about anything short of a urethane-based paint. Worst case it plugs up the tip and soaking it overnight in laquer thinner will take care of that.

Ok, I tried it (with a brush the coward I am).

It sticks very well. It has only been drying an hour and it won’t even scratch off with a fingernail. The colour I used was Bell Bronze (looks like a shiny gunmetal).

I’m not going to try it with the airbrush though. I think it may be more suited for an external mix gun.

MaxH

There really isn't any paint specifically "For" airbrushing or "Not" for airbrushing. It's how you thin it, set your pressure, and the nozzle on the particular airbrush. Given enough pressure and enough thinning you can eventually get virtually any paint so spray through an airbrush, but the results may not be what you wanted.

Those "Paints" are advertised on the site you showed as being "Ink", and if that's the case you should be able to get them to airbrush. What the results are going to look like I have no idea. If the pigment is large, which is common with metallic paints, you may have a difficult time getting it through the nozzle. Since they are advertised as "Ink" that leads me to believe that the pigment will be quite small. If you just really want to use them, I'd suggest playing around with it and see what it will do. The results might be quite good.

One thing to keep in mind is that, as Tom pointed out, some artist's acrylics are not intended for use on plastic. They are primarily for surfaces that are porous such as canvas, cloth, or paper. When used on plastic they might look fine but as soon as you touch the paint it rubs right off because it couldn't adhere to the surface. On the other hand, other artist's acrylics do quite well on plastic. Again, my advice would be to try it on some scrap and see what happens.

PS I’ve now found a site claiming that they are NOT suitable for airbrushing.

Typical. I buy an airbrush for the first time and then go and buy the wrong paint!

Doh.

QUOTE: Originally posted by tho9900 Well all paints have suspended particles in them for the most part, some larger some smaller. Typically acrylics and metallics can have larger particles while enamels and lacquers have smaller..... if you use the medium needle and head for the 150 you should be ok with all paints. The fine head will work with very thin paints like enamels and inks. The large head is almost useless for models as it has such a large spray pattern... I did a search for the type of paint and only came up with tube acrylics... I think you would have a very hard time using these in an airbrush. Do they make a type in the bottle? Typically bottle artists acrylics do not adhere well to plastic at all and tend to bead up when sprayed on it. If you are painting models, you should look into using model acrylics, most of them aren't water based like the artists acrylics. There is a type that is water based by the name of Vallejo which are superior acrylics in my opinion. My suggestion is go to a model shop near you and ask the shopkeeper there. He can get you into paints that will do the trick. And most model acrylics can be thinned with alcohol or a name brand thinner (like Tamiya) and cleaned with ammonia based window cleaner.

Thanks for the response.

I had the same problem researching the acrylic paints I bought. The product is supplied in liquid form in 1US fl.oz bottles, but there seems to be no info on them. Plenty on the tube acrylics, none on the liquid version.

I didn’t know there were two versions of acrylics so that info is very useful. I’ve now sound a site describing the product:

http://www.misterart.com/store/view/001/group_id/975/Daler-Rowney-Pearlescent-Liquid-Acrylic-Colors.htm

Nothing about using them with an airbrush – oops!

I’ve just changed the tip and needle to medium and are just about ready to go. I think this one will be a try-it-and-see job.

Cheers,

MaxH

I too am starting out on airbrushing after many years of using brushes. I have a load of Humbrol acrylic paints and (although the lable gives no clues) I`m guessing that they are for the model maker rather than the artist. Does anyone know if this is true please?

Well all paints have suspended particles in them for the most part, some larger some smaller. Typically acrylics and metallics can have larger particles while enamels and lacquers have smaller..... if you use the medium needle and head for the 150 you should be ok with all paints. The fine head will work with very thin paints like enamels and inks. The large head is almost useless for models as it has such a large spray pattern...

I did a search for the type of paint and only came up with tube acrylics... I think you would have a very hard time using these in an airbrush. Do they make a type in the bottle? Typically bottle artists acrylics do not adhere well to plastic at all and tend to bead up when sprayed on it. If you are painting models, you should look into using model acrylics, most of them aren't water based like the artists acrylics. There is a type that is water based by the name of Vallejo which are superior acrylics in my opinion.

My suggestion is go to a model shop near you and ask the shopkeeper there. He can get you into paints that will do the trick.

And most model acrylics can be thinned with alcohol or a name brand thinner (like Tamiya) and cleaned with ammonia based window cleaner.