I can't pre-shade to save my life

HI! It would help to know the airbrush or needle size too. I use MM acryl at times and they do ok for me but I have the pressure/thinner ratio down for my airbrush setup. occasionally I use Tamiya X-20 thinner for them and it works good too.

Airbrush is a Badger 360. Only has one needle/tip size. I thought of that but it's not a variable (other than  how much I "throttle" the lever with my finger).

Maybe you just haven't thinned it enough. I know you said you have tried various ratios, but what you're describing is a symptom of too thick paint.  I use MM Acryl with their universal acrylic thinner at 12 to 15 PSI. I don't measure ratios, but I would start at a 50/50 ratio and keep adding thinner until it stops spattering. Don't be afraid to thin that paint more.

Are you mixing the paint in the paint cup? One thing I learned was when I mix paint in the cup, I put the thinner in first then add the paint. I got better results that way.

Bottom line is I don't think there is anything wrong with MM Acryl paints.

Chris

Check the needle and nozzle for damage and/or paint build-up.  Even a small crack on the nozzle shroud can affect spray performance.

Secondly, you might want to increase the thinner to paint ratio and then try dialing the pressure down.  Even for regular painting, I use only 12-15 PSI, and that is with a bottom-feed airbrush.  Your 360 can be used as a gravity (top) feed, so it should be able to handle thinner paint mixes.

And finally, you don't have to get perfection when pre-shading.  Just spray a thinned mix of the final color in between the shaded areas to bring the lines down to your desired width.  If you overshoot, apply the shading color again and repeat as necessary.  This is what I do.

HTH

Well, I just finished up a session of experimentation. You guys are right. It's not the paint itself. This time I sprayed some Tamiya Dark Gray with their thinner, and results were the same. So obviously the thinning ratio or air pressure is the key.

   Usually when I thin, I'll just dribble a few drops into the paint until I get that "2% milk" thickness that everyone talks about, so I don't adhere to a ratio, per se. If you guys are going up to 50/50 paint to thinner ratio, then it seems I'm still running it far too thick.  I seem to remember trying it that thin before, though, and the paint came out very watery and ran everywhere.

  I guess more experimentation is in order.

  Thanks for the help so far.

  Chris

I think Tamiya acrylics are easier to work with. If you use denatured alcohol with their flat paints they can be thinned way down and still give good coverage. Thin Acryll too much and it just wants to bead, splatter and run. Over reducing enamels doesn't work all that great either. The key to any paint is finding the point your thinning ratio and air pressure allow you to get the results you need and that takes experimenting and practice. So...

If you're using a bottle on your 360 you're probably going to have to stay around 18psi and up. Maybe just a little lower. The higher the pressure, the less you'll have to thin.  If you're using the cup you can probably go down to 10-12psi or maybe just under but you'll need to thin more. Just my opinion but I believe that's where the double taper on the needle comes into play. It can be hard to hit the sweet spot and shoot just the right amount of paint. Just as you get there it wants to tip over and shoot too much. It takes practice and experimenting.

The 105 Patriot needle/tip/regulator will work on the 360. The standard setup on the 360 is an .070 needle and tip, standard on the 105 is .050 I believe. There's also a Superfine tip and needle that is .030 or .020. They will all interchange you just need the complete set, as in needle, tip and regulator. The standard 105 combination is easier to control. At least I think it is. I have the Superfine set too but haven't played with it a lot.

 If you already have a good selection of Acryll then maybe a bottle or two of dark Tamiya paints to use for pre-shading would be a solution.

Tony

Thinner paint needs lower pressure but you can get closer and make a finer, tighter line then, Keep trying with thinner paint, ever decreasing air pressure and getting in close until you have the look you want. Yes, a .70 needle may never give pencil line thin results, but pre shading does not have to be precise. A little wonky makes it look more natural and not toy like and perfect.

Hello!

Chris, I don't think it's necessary to lower the air pressure at all costs. If you have the paint flowing nicely, then you have to move the airbrush tip closer to the surface, to get a fine line. When you are close, too much paint starts to be an issue - that's why you need a good feeling on the trigger - the trick is to open up on the paint just a little bit. It's also a good idea to start moving the airbeush first, and open the paint flow after the airbrush is moving, to prevent starting each line with a "blob" - ending the line is similar - first stop the paint, thaen stop moving the airbrush. Hope it helps, good luck with that preshading and have a nice day

Paweł

Chris

I airbrush at 50/50 mix using the same thinner as the paint manufacturer. If its running you may have the pressure too high, or your trying to put too much paint down. Do check the paint tip as I split one on a Badger 150, its very easy to do but very hard to spot - I ended up using a jewelers magnifiyer and could only just see it then.

Phil

montague

Thinner paint needs lower pressure but you can get closer and make a finer, tighter line then, Keep trying with thinner paint, ever decreasing air pressure and getting in close until you have the look you want. Yes, a .70 needle may never give pencil line thin results, but pre shading does not have to be precise. A little wonky makes it look more natural and not toy like and perfect.

I concur.  Not only does thinner paint like a lower pressure, lower pressure likes thinner paint.  With proper thinning and pressure, needle adjustment, and technique, even a DA airbrush can produce fairly thin and transparent lines.

I like the 360 a lot. It's extremely versatile. It was my only airbrush for quite a few years. But, it can drive you crazy trying to do what Chris wants to do with it. And as I said before, in my opinion, the problem lies in the double taper .070 needle. Not because it's an .070 needle, but because of the tapers. And low pressure magnifies the problem. If you look at a 360 needle you'll see that the first taper isn't very long so it doesn't take a lot of needle movement to get to the second taper. The lower the air pressure goes the longer it takes for paint to start flowing so you've used up most of the first taper just getting paint to come out of the tip. Then you're right at the transition point of the tapers and as it tips over to the second taper you get a lot more paint flow. That can be hard to control.

I think you were on the right track with a little higher pressure but maybe your paint was a little thin for that pressure. It's a fine line. I do think MM Acryll thinner works the best.

The reason I suggested the Patriot needle combination is not because it's .050 vs .070 but because of the difference in the tapers. It is much easier to control for detailing because the transition isn't as steep. Just my opinion but I don't think the double taper on the .050 needle does or matters much at all.

Tony

Wingman, I think you've nailed it. I may try picking up some other needle sets if finances permit, down the road. Here's a shot of what I "accomplished" on the F/A-18E I'm working on. Not real happy.

Chris, I finally got a chance to hook up my 360 today. It's the first time I've sprayed any Acryll for quite a while and I didn't have much luck. Tip dry was driving me crazy. I tried it with a bottle and just using the cup. Got it a little too thin and got so aggravated with tip dry I didn't thicken it to try again. Then I tried some Tamiya black and while tip dry wasn't a problem it was difficult to get consistent results with too. It seems hard to get paint flowing consistently. I'm not a pro and don't do this every day but it's kinda like riding a bike, once you get the hang of it, it sticks with you.

My brush was refurbed by Badger 2 or 3 years ago and has been used very little since. It has a new needle and tip, new needle seal, rotary joint and air valve. I also have the 105 needle, tip and regulator. Tried both of them and the finer needle and tip was easier to control but  there were still quite a few times that paint just didn't want to flow and when it started it was too much and would splatter. No matter what the air pressure, bottle or cup.

You may already know this but if you're going to stick with Acryll you'll need to wipe the tip of the needle often. Acryll doesn't seem to be too bad if you're constantly spraying with a little wider coverage but detailing and starting and stopping increases tip dry. Oddly enough, lower air pressure seems to also. With either paint I got better results if I shot a little paint off the model, kept the air on and then started spraying again on the model. Occasionally pull the trigger all the way back for a couple seconds too. With the Tamiya paint it wasn't building up on the needle but must have been inside the tip because after a few lines paint wouldn't flow until I went off the model and pulled the trigger back.

Looking at your picture it seems that we were having the same problems. Wish I could be more help.

Tony

I've had the same experience as Tony when spraying acrylics, and it drove me bonkers.  However, when I tried using lacquer thinner with Tamiya acrylics, the airbrush performed like it was spraying enamels.  (Well, it kind of was, given the solvent used.)  Of course, this will not help one bit if you are trying not to poison the household with lacquer thinner fumes.  Others have mentioned a retarding agent to prevent acrylics from clogging the airbrush, but I have not tried any.

I think we're about on the same page, Tony. What did it cost you to have Badger refurb your brush? Mine is due for that, I think.

After a light coat of the base color over my pre-shading, I decided I'm ok with the results. Not happy, mind you, but ok. It will at least lend some color variation to the various panel lines, etc. when I get the top coats and a flat coat after decals. That's a few weeks off, though, I think. I think my issue is I'm just asking the brush to do something a little too far outside it's scope.

At this point I think I may experiment with some weathering powders on the panel lines after I get my base coat on. Then I can fade it a bit further with another misted base coat. I think I can create a nice faded weathering that way, and if I can get it to show up after sealing with a clear coat, I may do this as an alternative to pre-shading. We'll see.

  Thanks for the help and support so far, guys.

 Chris

All it cost me was shipping to them. They covered the return shipping. Both the needle seal and rotary joint were pretty worn and I guess the air valve was too. I bought the needle and tip. I think I did call them first and was told to include a note saying what problem(s) I was having. I just asked to have the needle seal replaced. Actually, I think they replaced the front section of the brush from the rotary joint forward but they did put my air cap, regulator and tip back. I painted a lot of cars with that brush and it was great for that. Trust me, it was well worn.

Tony

Well, that's one of the advantages of enamels, I couldn't pre shade w/AB to save my life (besides, I hate cleaning it) so I just use a black permanent marker.