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AB issues,, still a struggle


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Hi,

I had to strip my 308 yet again due to orange peel.  It was too much for a simple polish to fix, at least for me.

So I'm finding that my particular paint jar is orange peeling quick.

I've tried various ratios and so far the smoothest coat is achieved by;

505/50 Taimya Red; X-7 with Tamiya Thinner; X-20A

Spraying at ~15 PSI

Being 2-3 inches close to the model.

I really don't like being that close so I'm reaching out to see how you all deal with this sort of situation?

Is it normal to be that close when air brushing?

.

 

Edited by aurfalien
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Sorry, but I have no specific recommendations as to AB pressure, viscosity, distance, etc.

What I DO heartily recommend, however, is to scuff and primer some small plastic pop bottles. 

Sand and prep them as close to exactly like you're doing to your models, and practice, practice, practice.

To shoot an orange-peel-free coat of anything, you're pretty much within a gnat's-whisker of running the stuff, and it's a skill that takes time to master and judge correctly.

Once you can consistently lay down a slick paint job on a bottle, with little or no peel, and just know by the feel and sound of your paint if it's the right viscosity, only then are you really ready to take that skill to a model.

When I started painting big cars (over 40 years back) there's no way I could have or would have gone into a booth and just started spraying.

I practiced for hours on end, on junk panels, to get the feel of the guns, different materials, mix-ratios, etc.

And to this day, because I don't paint on a daily basis, I ALWAYS practice and warm up...whether painting on real cars OR models...before I work on something that matters.

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My preferred testing medium is a white plastic spoon. Same plastic as our models, cheap, and the curve on the back side gives you some idea of what it will look like on a fender. I got a lifetime supply at Costco for $10. 

Orange peel is caused by the paint being too dry when it hits the model. The two possible cures are more solvent, and/or a slower drying solvent. Also make sure you're putting down enough paint. The part should be wet, and you'll have to discover the difference between enough paint and runs. This is all best done with spoons. 

Another factor which you don't control is humidity. On a dry day, the solvent will evaporate more quickly. I see you're in Ventura and I presume that you're in SoCal too. I don't spray paint anything when there's a Santa Ana. It's too windy, and I have yet to find a solvent that evaporates slowly enough. 

My own experience with airbrushing Tamiya was a disaster, and I haven't tried since then. 

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My preferred testing medium is a white plastic spoon. Same plastic as our models, cheap, and the curve on the back side gives you some idea of what it will look like on a fender. I got a lifetime supply at Costco for $10. 

Orange peel is caused by the paint being too dry when it hits the model. The two possible cures are more solvent, and/or a slower drying solvent. Also make sure you're putting down enough paint. The part should be wet, and you'll have to discover the difference between enough paint and runs. This is all best done with spoons. 

Another factor which you don't control is humidity. On a dry day, the solvent will evaporate more quickly. I see you're in Ventura and I presume that you're in SoCal too. I don't spray paint anything when there's a Santa Ana. It's too windy, and I have yet to find a solvent that evaporates slowly enough. 

My own experience with airbrushing Tamiya was a disaster, and I haven't tried since then. 

I agree with everything Dave Ambrose has to say here except...

1)  The plastic that spoons are made from is considerably harder and more solvent-resistant than the formulations the model manufacturers have been using for several years, at least. I can spray hot primers and colors on some spoons with no crazing. The same materials sprayed directly on many models will ruin them. All "styrene" is NOT created equal.

2)  It's impossible to develop proper overlap technique painting spoons. They're simply too small. If the correct amount of overlap between successive passes with the airbrush (or rattlecan, for that matter) is not achieved, you'll either get runs or the resulting dry edge will almost invariably produce undesirable orange peel, at least in some areas. You couldn't possibly learn correct spray technique for real cars by painting toilet seat covers, which have about the same surface area relationship to a car as a spoon has to a model.

This is why I now recommend practicing painting with pop bottles. They are roughly the same size as a 1/25 scale model car, they have varying surface features, and they need to be turned to get complete coverage and correct overlap, just like painting a model car body.

Edited by Ace-Garageguy
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Hi and many thanks.

My spoons turn out wonderful but man is it different for me when it comes to a car body.

Even my spray technique changes.

I wished the car body were like a spoon for me but its night and day.

I'm now using a spoon as an approximation on color, that's pretty much it.  Also to see how the paint may behave/perform as well.

i was VERY disappointed that my attempts on the car body were soooooo different then a spoon.  In fact I almost cried as I am trying so darn hard at this.  I used up an entire bottle of X-7 between practicing on spoons and stripping my car body.  I ran out on my 2nd final coat when I just about finally got it down.

Edited by aurfalien
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...My spoons turn out wonderful but man is it different for me when it comes to a car body.

Even my spray technique changes.  And that's why I started using old junk bodies, and then plastic bottles, to practice on.

I wished the car body were like a spoon for me but its night and day.

I'm now using a spoon as an approximation on color, that's pretty much it.  Also to see how the paint may behave/perform as well.

i was VERY disappointed that my attempts on the car body were soooooo different then a spoon.  In fact I almost cried as I am trying so darn hard at this.  I used up an entire bottle of X-7 between practicing on spoons and stripping my car body.  I ran out on my 2nd final coat when I just about finally got it down. That bites, but I can identify. I once had a similar issue painting a real Mercedes in a light metallic blue with just a touch of purple, a custom color. Because I had some problems with trash and graininess, I ran out before the job was done, the second batch didn't match the first, so each side of the car was a slightly different color, blended down the center on the hood, roof and decklid. After it was cleared and polished, nobody ever knew...except me.  

Hang in there. You'll get it.  B)

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One rule of thumb I use when getting paint ready is this:

Swill the jar around....when the paint washes away and you just see "film" on the jar, then it's ready for me. If the paint still looks "solid" (as if the jar is full), then I know that I need to add more thinner as the paint is still too thick. Too thick of a paint can lead to your orange peel effect as the paint is not "flowing" as it's hitting the surface. As with anything else------Practice, Practice, Practice! This might sound crazy, but I've found that certain colors seem to take more thinner than others. Reds for instance as opposed to white. Possibly because of the "tightness" of the pigments?

If your color is a metallic, it might be a VERY good idea to put a metal ball or two in your paint jar. This will keep the metallic flakes suspended (swill the jar occasionally), and prevent yet another surprise.

You can best believe when it comes time to paint my Green Hornet body (months from now), I'm going to be trying the paint out on a junk body. The paint I'll be using will be a custom mix as there's nothing out there that comes close enough to suit me.

Same here. Went back to enamels for airbrushing. I do use some of the Tamiya lacquers straight from the can, though.

That's what I'll be using when it comes time to paint. Takes longer to dry, but I don't want any surprises after all this work. Tamiya's paints are OK as far as it goes, but man they sure do wear away quickly when it comes time to rub out and polish! :o

Another thing I don't like about Tamiya's spray cans is this:

I'm not sure what Tamiya's paint process is when it comes to manufacturing their paint, but I've found that they're using WAAAAY too much propellant in their cans! I've tried to decant certain colors of theirs in the past, only to have the jar constantly "burping" with propellant hours after I've had it in the jar. I've had to let it sit at least overnight to let a lot of the propellant gas itself out. Failing to do this, you'll end up with all kinds of little bubbles in the paint which can look like orange peel but isn't.

Just a word of caution!

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One of your issues with painting may be the choice of airbrush. When you say ab I assume you are talking about a pasche. The ab is for illustrators and has really fine control.  This might also explain why the spoons come out looking good.

You might be better off with an h(single action) or vl(dual action).  

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Hi,

Well mine is the Harder & Steenbeck Infiniti which I am getting very used too.

I think it simply takes time, for me especially.

I can totally understand how articles are reluctant to mention a formula of pressure, distance and thinning that always works.

 

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When I started airbrushing (3 years ago approx) I had all kinds of trouble with orange peel. After a lot of trouble (especially lacquers like nail polish), it was noticed that the problem was worst during warm days. The lacquer would go on much better during cold days, as it would dry slower and flow easier. This led me to do some research, and found that the you could buy some lacquer thinner with a retarder mixed in (or seperate if wanted). A good example is Mr Levelling thinner. Once using this stuff, I have had minimal problems spraying lacquers. On hot days, I even mix some with the decanted tamiya spray paint. It is like magic!!!


Most cars I build now, I don't really sand the base coat unless I have dust stuck to the surface. Once done, its just a matter of doing two coats of 2k clear and the finish is like a mirror. Once again 2k clear flows really well and drys very slowly, making it easy to achieve a mirror finish. Just as a note, I don't enter contests etc, but am very satisfied with the finish using these techniques.

Hope this helps

Mike

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Hi,

Well mine is the Harder & Steenbeck Infiniti which I am getting very used too.

I think it simply takes time, for me especially.

I can totally understand how articles are reluctant to mention a formula of pressure, distance and thinning that always works.

 

What size of tip are you using in your airbrush? I use a number 5 in my Paasche VL, and it still seems a bit small sometimes. 

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I agree with everything Dave Ambrose has to say here except...

1)  The plastic that spoons are made from is considerably harder and more solvent-resistant than the formulations the model manufacturers have been using for several years, at least. I can spray hot primers and colors on some spoons with no crazing. The same materials sprayed directly on many models will ruin them. All "styrene" is NOT created equal.

2)  It's impossible to develop proper overlap technique painting spoons. They're simply too small. If the correct amount of overlap between successive passes with the airbrush (or rattlecan, for that matter) is not achieved, you'll either get runs or the resulting dry edge will almost invariably produce undesirable orange peel, at least in some areas. You couldn't possibly learn correct spray technique for real cars by painting toilet seat covers, which have about the same surface area relationship to a car as a spoon has to a model.

This is why I now recommend practicing painting with pop bottles. They are roughly the same size as a 1/25 scale model car, they have varying surface features, and they need to be turned to get complete coverage and correct overlap, just like painting a model car body.

I haven't run into any problems with spoons vs. bodies, but that might just be luck

You second point is well taken. I'll have to try that. 

I haven't run into any coverage problems with opaque paints. My technique is to go find the corners and other hard to get to spots, and spray them with a light coat first, then spray the main areas going front to back, then change the direction 90 degrees and spray again going side to side. Learned that painting rockets and aircraft. It seems to work well.

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My advice: ditch the X-20A and use Lacquer Thinner.  Specifically Mr Levelling Thinner if you can get it.   But Tamiya Lacquer Thinner is not too bad.  And thin it more than 50/50. 

Excellent advice; I've been told Tamiya developed their lacquer thinner specifically for their acrylics so they would spray and lay down on the surface like traditional solvent-based paints. Mr. Thinner/Mr. Leveling Thinner can be used for the same jobs as Tamiya lacquer thinner. I use Mr. Thinner products all the time to thin decanted paints and when shooting flat acrylics I use on interiors, and thinning Mr. Hobby solvent-based bottle paints. X-20A just for occasional panel line washes.

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 My technique is to go find the corners and other hard to get to spots, and spray them with a light coat first, then spray the main areas.

I do something similar. I lay a coat on all door/panel lines, and on all sharp edges or creases, and then a second coat in these areas, and only then will I open up the nozzle and start laying paint on large areas.

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Still have yet to understand why so many use lacquer thinner to thin thier paints. If you are getting orange peel then you are dealing eith paint flow an it drying to fast. I would assume lacquer thinners are made differently an you probably won't figure out the temperature at which to spray lacquer. Find a automotive paint atore an invest in a proper reducer for your temperatures. I own ppg 70 an 95 an do great.

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Still have yet to understand why so many use lacquer thinner to thin thier paints. If you are getting orange peel then you are dealing eith paint flow an it drying to fast. I would assume lacquer thinners are made differently an you probably won't figure out the temperature at which to spray lacquer. Find a automotive paint atore an invest in a proper reducer for your temperatures. I own ppg 70 an 95 an do great.

i don't know why it works I just know it does.  I struggled with Tamiya Acrylics, glosses orange peeling and flats gritting up for years, switched to MLT - boom, no more problems. It's like a different paint all together.  Mr Levelling Thinner is liquid magic as far as I'm concerned.     

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i don't know why it works I just know it does.  I struggled with Tamiya Acrylics, glosses orange peeling and flats gritting up for years, switched to MLT - boom, no more problems. It's like a different paint all together.  Mr Levelling Thinner is liquid magic as far as I'm concerned.     

Hi,

Is it T-106 by chance?

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I haven't done a lot with acrylics through the airbrush.  But I use the cheap BLAH_BLAH_BLAH_BLAH lacquer thinner from the hardware store, so long as it mixes with the paint - you can usually tell pretty quick.  I can still mix and lay down an acceptably smooth paint job with my old Paasche VLS.  Same airbrush since 1991.  I have replaced ALL the internals at least once - like George Washington's axe.   The body is the ONLY original part.  I use the #3 parts.  I have used high pressures and am experimenting with lower pressures now, but think I still like higher pressures best.  Probably 4 - 6 inches from the body.  At 2", I'd be blowing the paint into puddles with waves - maybe you're too close?  Takes experience to find the sweet spots in all of this.  And sometimes, the paint has to have time to flow out.  

I have no idea what ratios - I just mix it til the paint "feels" thin enough - like Bill said, it can't be solid in the jar - has to be translucent or it's not thin enough.  Can't be too thin or it turns to a "wash".  Unles you go realllllly slowly and build it up.  But that just doesn't seem to work right.   Most paints out of spray cans are pretty close to sprayable right out of can.  Even if they feel right, I usually add a few drop of lacquer thinner to help it dry quicker.  

I gave up on polishing to glass a long time ago.  For me, what's the point?  Takes too long and too much chance to mess it up completely.  A factory paint job on a 1:1 or even diecast or whatever is never perfectly glass smooth.  And I don't compete, so takes that out as well.   If it's too stressful, relax your standards a bit to where it becomes fun, or let someone help you that is an expert painter in your circle of friends - do modeler's have friends/??  A lonely pursuit in my area.  

Good luck finding that"right" combination.  Use some old bodies to practice - you're going to wear that body out stripping and painting.  : )

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I agree with others about the cause of orange peel. The spoon thing (too small to get your technique perfected) might also apply here.  Find a larger test object, install the larger nozzle, crank up the pressure to 20 psi and open the needle wide while spraying (to increase the paint flow). You will most likely also need to move the airbrush further away from the sprayed surface.  Like it was said, to get a smooth layer of paint you need to spray on a wet coat.

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