Mottling Question

I am getting ready for the mottling, and I have been practicing on some scrap. I think I have the thinning about right and I set the compressor to give me about 12 psi. I am using acryls and the problem is that I get a couple of fine lines and then the paint dries on the tip of the airbrush. Too little pressure I think to keep it moving so to speak. I am having no issues with the “standard” airbrushing.

Here is my question; should I keep experimenting with the mix, add a retarder to slow down the drying, or I was just thinking about making a mask/template from a sheet of paper or Scotch Blue and just using that. I am new to trying to mottle the schemes and am not sure how you all got to be experts!

Thanks.

John

Retarder, patience & regular tip cleaning…

It think retarder is your best bet. But airbrushing in general and motteling in particular is not an exact sience.

Yes, keep experimenting. One of the reasons I prefer enamel over acrylic is that I have also had deposits in the airbrush because if its quick drying. Even with enamel, in a long session I find some enamel building up on needle and in tip. I keep Q-tips handy when I am airbrushing. When I notice any buildup, I put the thinner bottle on and hold the q-tip up to the nozzle. This wets the q-tip with thinner and I twirl it around a bit to clean the needle tip and nozzle.

I also use this technique during a temp/quick cleaning when I am done spraying, if I am not going to take the brush apart for cleaning in the current session.

John,

I’m also experimenting with mottling in prep for mottling an FW190 and am having the same problems as you. Retarder and Flow-Aid has helped a lot but doesn’t eliminate the problem - I think it’s just the ‘nature of the beast’ and my slowness when using acrylics. I do use a gravity feed AB so can’t use Don’s ‘switch to thinner’ technique but I keep a small separate container of thinner handy and when I see I’m getting some tip-dry, I dip a Q-Tip in thinner, retract the needle, clean the air cap with the Q-tip, then slowly release the needle while slowly rotating the Q-tip - I do this carefully - ! It seems to work but after not too long I have to repeat because I’m so slow at it. When using retarder and Flow-aid I can make ‘splotches’ easily for quite some time on a piece of white cardboard but when I draw a profile of the fuse on the cardboard and try to mottle where I want it I am truly slow so it’s more practice, practice for me. Anyway that’s how I deal with tip dry. Hope you can find a better solution.

B

I am going to pick up some Flow-aid on my way home tonight and give it another go. I have thought about using enamel for the mottling, but I don’t like the cleanup. I love the acryls for that.

Thanks for all your replies. I’ll let you know how it turns out.

John

OK, purchased two products today. I stopped at the art store and talked to the guy after doing some research. I got a flow-aid and a retarder. Both are from Golden Mediums. I have no idea about that brand as I was expecting Liquitex.

Anyway, I mixed it up as follows:

1 drop medium airbrush flow-aid

1 drop retarder

2 drops of acryl thinner

Then by experimentation, anywhere from 4 to 8 drops of acryl paint

I then played around on some paper with PSI from 12 to 8. Seems to work pretty well. The tip did not dry out for a long time. I used the Q-tip in thinner and wiped the tip and sometimes just pulled it back. Seemed to do the trick as long as your first spray after that was on something you don’t want as it was kind of wet.

When I went to the plastic, the mix was runny. The best pressure seemed to be 8 - 10 PSI. There was still some “grainy” spray around the line or circle splotch I was making. If I went be low 8 PSI, I got just chunks of paint. More than 12 PSI and I got splotches as I was too close. I stayed about 3/4 " from the surface. I think there were some decent lines, and some crappy ones. I will spray back over the bad areas and try again.

I will try to upload a couple of pictures I took if I can figure out how:(

The medium and retarder didn’t seem to mess with the paint result at all, so at least after one try I give the concept a thumbs up.

John

Here is a port and starboard view. Please be gentle, I’m learning…

http://www.flickr.com/photos/84704985@N08/7750572536/in/photostream

http://www.flickr.com/photos/84704985@N08/7750572234/in/photostream

John

Hi John, it looks to me like the paint is too thin for the pressure you are spraying at. You can spray very thin paint, but at a very low pressure, 4-6 psi, and built up slowly with constant small movement of the airbrush. For anyone building Luftwaffe aircraft I would highly recommend Floyd Werner’s Master Class DVD on building the Bf-109. There is a good segment on mottling and he does use acrylics. This DVD made a huge improvement in my modelling and has been the best money I have ever spent in scale modelling. That said, I switched from acrylics to Gunze Mr. Color a few years ago and can’t figure out why anyone would use anything else. Good luck, Jay

Jay;

Thanks, I ordered the DVD and am looking forward to watching it when it arrives. I am going to have to keep messing with the “formula” for the paint. Whenever I get the density right, it seems to thick to spray unless the pressure is such that I cannot get as close as I need. Oh well.

I have attached two more photos. One of the 190 where I sanded out the spiders and splotches and then sprayed over it with a very thin RLM 76. I don’t get the crispness I was looking for but I am happy with the result.

Second is a 1/72 Me-109, where I made my own mask and sprayed. Too sharp on the lines, but so much better on the density and detail.

http://www.flickr.com/photos/84704985@N08/7784803576/in/photostream

http://www.flickr.com/photos/84704985@N08/7784803272/in/photostream

Thanks again.

John

John,

I think you will get a lot out of it. I have watched it many times. I even made a point of going to a show I knew Floyd would be at to thank him personally. I think most of getting better is having the patience and desire to practice enough to get better, but sometimes a little outside help goes a long way too.

Jay

Amen to that. I’ve got bottles of Liquitex Airbrush Medium, Liquitex Flow-Aid, and Golden Retarder I’ll sell for the price of shipping. I don’t put acryls through the airbrush anymore, as I just got tired of the constant alchemy required for fine camo or mottling. And the worse part to me was getting it figured out one day and then trying the exact same mix the next and having it not work anywhere near the same due to different environmental conditions (humidity / heat).

Switch to Mr Color and you’ll realize you’ve changed to easy mode for airbrushing. It’s amazing how much more fun ABing became when I didn’t have to fight the mix anymore… it just works.

I still use the acryl collection for small parts and brush painting, but I don’t spray it.

I keep to acrylic because of the odor of enamel and lacquer. Even with proper venting, i have to share my space with the family, which objects to the much, much stronger odor.

I actually like MM Acryl and Tamiya acrylics and still have a couple hundred bottles of them, but they are far from odorless. I don’t think my wife complains any more now than before and she has a bionic sense of smell. I think she is more concerned about the health risk and does check to make sure I have my respirator on. Anyhow, whatever it takes to keep using Mr. Color , I am doing it.

Vallejo Model Air is pretty close to odorless, but Tamiya certainly isn’t… especially with X-20A. MM Acryl smells really ‘musty’ to me, as well. I should mention I don’t distinguish between Tamiya and Mr Color… thinned with Mr Leveling Thinner they both work so perfectly it’s hard to tell them apart. X-20A works well too, but the odor is much stronger, and it dries almost too quick.

I’d hate to recommend something that turns out unacceptable due to nasal sensitivities, but if you’ve got a few dollars you’re willing to experiment with then get a bottle of Mr Color and the small container of Mr Leveling Thinner. The odor isn’t bad at all… nothing like enamels. I don’t know what Gunze does to their products, but the smell isn’t unpleasant. I’m sure they add something.

Once you see how smoothly it sprays at virtually any density right down to near transparent you’ll be hard pressed to continue messing around with spraying acryl.

John,

You could try making a template for your mottling. To paint my Triebflugel, I used index cards with small, irregular holes burned into them with narrow diameter incense:

www.flickr.com/…/5751868620

The upside is that it is easy to get small, tight edged inkspots. But the downside is that the index cards are difficult to get around obstructions like horizontal stabilizers. You need to keep the airbrush 90 degrees to the card mask to get the best results.

HTH

Just my opinion but Tamiya flat acrylics thinned with denatured alcohol are about as close to using lacquers as you can get. Not quite the same but very close as far as spraying goes. And a little Windex will take it right off.

MM Acryl seems to be more suited to something that doesn’t require as much finesse as mottling. And even if you get a bottle that’s very thick it doesn’t seem to like a lot of thinner. It does exactly what you found; runs, spiders and splatter. It can be done but requires constantly cleaning the needle.

On the other hand, Acryl is pretty tough stuff once it’s dry. As long as the surface was clean or primed before you applied it. So, if you can deal with using Acryl for your basecoats then try using Tamiya for your camo or mottling. If you have a problem, slip, make a small mistake it’s easy to clean up with a brush moistened with Windex. Kinda like drybrushing in reverse.

And, if you decide you like Tamiya and want to use it for base coats too then try this. It does involve lacquers but MM Glosscote is pretty mild and the odor isn’t bad. Do your base coat with Tamiya then spray a couple light coats of Glosscote over the area you’re going to camo or mottle. Now when you do your mottling or camo you can clean up any mistakes with Windex without affecting the basecoat. No, Tamiya doesn’t offer near the amount of colors that MM does but lightening, darkening or shifting the color to suit you isn’t hard. And it’s a lot easier to work with than Acryl.

Tony

I did make a mask for my 109:

http://www.flickr.com/photos/84704985@N08/7784803272/in/photostream/

I made the shapes a little too large I think. I first drew out the shapes on a piece of writing paper. then I put two pieces of Scotch Blue tape under it. then I put a piece of Scotch Magic tape over it. It was flexible yet pretty durable. I then cut out the shapes with an X-Acto knife. I then lightly attached the mask to the fuselage. I should have done a couple of sections rather than one big piece as you said it was a little hard around the stabilizers and wings. I trimmed it more as I placed it.

Thanks.

John

Well my two big things I like about the acryls are the color selection, and the cleanup (no smell). I spray indoors and I have a vented spray booth, but I don’t want to be using Turpentine-ish stuff for all the clean up. I sprayed one kit with an enamel rattle-can primer and it took about 4 days to get the smell out of it all. I am finishing it up with acryls (the model we are talking about).

Now if Mr. Color cleans up with Windex, then it may just come down to the smell in the room when painting. Not sure as I have never used Mr. Color. I don’t recall seeing it in the two hobby shops I have gone to; Hobby Lobby, and Hobby Bench here in Phoenix.

John

Mr Color has an incredible color selection (300+ last time I looked), but it does have some odor though it’s not necessarily a ‘bad’ odor… somewhat in the nose of the beholder. Enamels, to me, have a very definite and universally unpleasant smell. Plus, as you note, enamels can take days (even weeks for some glosses) to completely cure, and they’re putting out an odor that entire time.

Lacquers dry near instantly, much like most acryls. The Leveling Thinner Gunze makes actually has a retarder in it to counteract this and allow the paint to ‘level’ out a bit before curing, but it’s still a matter of minutes, not days. The smell is gone pretty much the instant the direct spray fumes are vented out.

Mr Color is a true lacquer and doesn’t clean up with Windex… it needs lacquer thinner. I use the Mr Leveling thinner to thin the paint for spraying, and a $5 can of Klean Strip Green to clean the AB. The Klean Strip Green has a somewhat aniceptic smell… not great, but not offensive either. Enamels and the standard Testors Enamel Thinner are 100X worse to my nose (and more importantly, my wife’s.)

You can’t buy any of the Gunze stuff off the shelf in the US. The only english lettering on the bottles is the color name… everything else is Kanji. Most of the major online hobby stores carry it, however. I usually buy from Hobbywave, as they have a fixed price of $12 shipping for up to 50 bottles. Very expensive if you only need a few, but great for stocking up. Sprue Brothers also carries it and has better shipping for just a bottle or two, but typically has poor stock levels.

If you’re in the North Texas area send me a PM and come on by… check out the smell in person. :slight_smile: