Gloss painting techniques. Help!

[luftmodels]

Hello guys 👋 

 

I tend to struggle with gloss paint. So far it is hit or miss even using exactly the same paint. I don’t have problems with any other kind but gloss (Tamiya, Mr Color). Could someone share their tips and expertise? I would highly appreciate your effort. 🙏🏻
 

Many thanks.

[dnl42]

The key is to first build a base coat with color coverage. Spray thin coats, close-in, 0.25 to 2 inches, making sure the paint is slightly wet when it hits the surface. Only then do you apply a final wet gloss coat.

[luftmodels]

17 minutes ago, dnl42 said:

The key is to first build a base coat with color coverage. Spray thin coats, close-in, 0.25 to 2 inches, making sure the paint is slightly wet when it hits the surface. Only then do you apply a final wet gloss coat.

hank you for your reply. I would assume everything above primer coat. Am I correct? Very often I get sandpaper like surface when I do first thin coats. Then I spray more and get even rougher sandpaper. I guess I hold my brush too far. Definitely more than 2 inches. How many in total coats do you do including first mist?

[Graham Boak]

Rub down between coats.

[luftmodels]

1 hour ago, Graham Boak said:

Rub down between coats.

With sand paper?

[dnl42]

On 8/4/2020 at 10:25 PM, luftmodels said:

hank you for your reply. I would assume everything above primer coat. Am I correct? Very often I get sandpaper like surface when I do first thin coats. Then I spray more and get even rougher sandpaper. I guess I hold my brush too far. Definitely more than 2 inches. How many in total coats do you do including first mist?

You're probably too far if you're getting sandpaper surfaces. 

 

This is how I paint.  

• Prepare the surface so it's as smooth as possible prior to painting. Polishing pads help here.
• Make sure there are no foreign substances on the model. I always wipe the model and all parts with 91% Isopropyl Alcohol (IPA) before painting. NEVER use hardware store lacquer (cellulose) thinner on plastic. 
• Thin the paint with the manuf's thinner unless an alternate has been verified to  work as well. For my preferred Mr Color, I use Mr Color Leveling Thinner (MLT). I use MLT for Colourcoat paints too, as I know it works well.
• Thin to the consistency of 1% milk. I thin only the paint I'll need for the specific session. I don't put thinned paint back in the jar/tin.

• Before adding paint to the airbrush cup, put 3 to 5 drops of paint thinner, NOT HW store lacquer (cellulose) thinner, into the airbrush cup. Start with just an airflow to ensure there's no fluid leakage past the needle. Then slightly pull back on the trigger so just a little fluid (thinner) is atomized. Make sure this starts smoothly and shows good atomization. Then go to full flow, again looking for good atomization. If any of this doesn't work, fix the problem with the airbrush and repeat until this step works. When this is done, you've ensured any fluid residue in the airbrush is fully compatible with your paint.

• Resin and metal must be primed. Multiple surfaces, for example plastic and metal, should be primed. I always prime everything. I brush Mr Metal Primer on all metal surfaces and then thinned Mr Surfacer 1200 (thinned as above) over everything (including the already primed metal surfaces).
• Set the full-flow air pressure to 15 PSI (1 atm). This means air (but not paint) is flowing through the airbrush. Static air pressure will be higher.
• Spray at 0.25 in to 1.75 in (5 to 45 mm). This can be a little tricky to manage, but is very important to avoid those sandpaper-like surfaces. The most important part is to not get too far away, so the paint doesn't dry before it hits the model surface.
• The paint should hit the surface slightly wet. Use a grazing light to see this. If the paint isn't wet when it hits the surface, you're going to get an orange peel, sandpaper, or worse.
• Use thin coats to build coverage. White and yellow can require many thin coats to get full coverage. As I use lacquers, which dry very quickly, I can get full coverage in a single session. If I have multiple small parts I'll apply a thin coat to each part in turn until I've built full coverage on all parts. On a full model, I'll do the same with different parts of the model. I'm pretty sure this can be done this with Tamiya too.
• If spraying a gloss color, only apply a final "wet" coat after full coverage. This is especially important for white and yellow.
• Wait until the paint is fully dry before masking. For enamels, wait until the paint has cured (several days, until off-gassing can no longer be smelled). With Mr Color, I can mask in 30m to an hour if I'm trying to hurry. 
• I primarily use Tamiya masking tape because of its good adhesion and low tack. I will also mask with Frisket film when I need a more complicated mask. Microscale Industries Micro Mask works well for solvent paints. I always de-tack masking tape by laying it on the palm of my clean hand before applying to the model.

Here are examples of gloss coats. No rub-down was needed along the way. 

 

 

HTH

-- 

dnl

[luftmodels]

3 hours ago, dnl42 said:

This is how I paint.  

• Prepare the surface so it's as smooth as possible prior to painting. Polishing pads help here.
• Make sure there are no foreign substances on the model. I always wipe the model and all parts with 91% Isopropyl Alcohol (IPA) before painting. NEVER use hardware store lacquer (cellulose) thinner on plastic. 
• Thin the paint with the manuf's thinner unless an alternate has been verified to  work as well. For my preferred Mr Color, I use Mr Color Leveling Thinner (MLT). I use MLT for Colourcoat paints too, as I know it works well.
• Thin to the consistency of 1% milk. I thin only the paint I'll need for the specific session. I don't put thinned paint back in the jar/tin.
• Resin and metal must be primed. Multiple surfaces, for example plastic and metal, should be primed. I always prime everything. I use thinned Mr Surfacer 1200 (thinned as above).
• Set the full-flow air pressure to 15 PSI (1 atm). This means air (but not paint) is flowing through the airbrush. Static air pressure will be higher.
• Spray at 0.25 in to 1.75 in (5 to 55 mm). This can be a little tricky to manage, but is very important to avoid those sandpape-like surfaces. The most important part is to not get too far away, so the paint doesn't dry before it hits the model surface.
• The paint should hit the surface slightly wet. Use a grazing light to see this. If the paint isn't wet when it hits the surface, you're going to get an orange peel, sandpaper, or worse.
• Use thin coats to build coverage. White and yellow can require many thin coats to get full coverage. As I use lacquers, which dry very quickly, I can get full coverage in a single session. If I have multiple small parts I'll apply a thin coat to each part in turn until I've built full coverage on all parts. On a full model, I'll do the same with different parts of the model. I'm pretty sure this can be done this with Tamiya too.
• If spraying a gloss color, only apply a final "wet" coat after full coverage. This is especially important for white and yellow.
• Wait until the paint is fully dry before masking. For enamels, wait until the paint has cured (several days, until off-gassing can no longer be smelled). With Mr Color, I can mask in 30m to an hour if I'm trying to hurry. 
• I primarily use Tamiya masking tape because of its good adhesion and low tack. I will also mask with Frisket film when I need a more complicated mask. Microscale Industries Micro Mask works well for solvent paints. I always de-tack masking tape by laying it on the palm of my clean hand before applying to the model.

I can't thank you enough for this detailed walk-through. Thank you so much!! I have no right to screw it up now. I will practice all these steps. Literally, thank you so much for your help. Your models and their shine are superb!! 👍🏻

 

Quote

As I use lacquers, which dry very quickly, I can get full coverage in a single session.

What do you mean under "a single session"?

[Tojo72]

I try to use flat paint when I can, then I will spray with a gloss like Alclad

[luftmodels]

7 minutes ago, Tojo72 said:

I try to use flat paint when I can, then I will spray with a gloss like Alclad

I was thinking about it but it is not quite the same as a natural paint shine. However, as a last resort, it will do. Thank you for confirming such variant.

[dnl42]

2 hours ago, luftmodels said:

What do you mean under "a single session"?

A single load of paint into the airbrush's paint cup. When painting multiple parts, I paint each part in turn, then apply another coat on each part. One session, multiple coats. For a complete airframe, I'll start with one part, say the empennage, then move on to the rear fuselage, one wing, the mid fuselage, the other wing, then the forward fuselage. I'll then repeat the process.

 

Oh, another tip is to put 3 to 5 drops of paint thinner (NOT HW store lacquer (cellulose) thinner) into the airbrush cup. Start just with an airflow to ensure there's no fluid leakage past the needle. Then slightly pull back on the trigger so just a little fluid (thinner) is atomized. Make sure this starts smoothly and show good atomization. Then go to full flow, again looking for good atomization. If any of this doesn't work, fix the problem with the airbrush and repeat until this step works. When this is done, you've ensured any fluid residue in the airbrush is fully compatible with your paint.

[Steve Noble]

If I'm using gloss paint such as Mr Color lacquer I don't do dozens of mist coats as I find the surface can be rough. I simply apply light, but wet coats of paint, it dries very fast anyhow, so there's no problem with it running or anything. I usually apply 3-4 wet coats, allow to dry, then a couple of final wet coats, a little heavier than my initial coats. Always works for me and leaves little work to do in the way of polishing. Usually a good shine/finish can be achieved straight from the airbrush.

[luftmodels]

2 hours ago, dnl42 said:

A single load of paint into the airbrush's paint cup. When painting multiple parts, I paint each part in turn, then apply another coat on each part. One session, multiple coats. For a complete airframe, I'll start with one part, say the empennage, then move on to the rear fuselage, one wing, the mid fuselage, the other wing, then the forward fuselage. I'll then repeat the process.

 

Oh, another tip is to put 3 to 5 drops of paint thinner (NOT HW store lacquer (cellulose) thinner) into the airbrush cup. Start just with an airflow to ensure there's no fluid leakage past the needle. Then slightly pull back on the trigger so just a little fluid (thinner) is atomized. Make sure this starts smoothly and show good atomization. Then go to full flow, again looking for good atomization. If any of this doesn't work, fix the problem with the airbrush and repeat until this step works. When this is done, you've ensured any fluid residue in the airbrush is fully compatible with your paint.

Thank you so much for your tips. I already started to see little improvements. Does it matter how fast we move our hand? Something tells me I'm doing it too fast. Can it be an issue?

 

27 minutes ago, Steve Noble said:

If I'm using gloss paint such as Mr Color lacquer I don't do dozens of mist coats as I find the surface can be rough. I simply apply light, but wet coats of paint, it dries very fast anyhow, so there's no problem with it running or anything. I usually apply 3-4 wet coats, allow to dry, then a couple of final wet coats, a little heavier than my initial coats. Always works for me and leaves little work to do in the way of polishing. Usually a good shine/finish can be achieved straight from the airbrush.

Basically you do 5-6 coats in total, don't you? A bit hard to grasp the concept of "light but wet coats of paint" . Basically this is 100% coverage unlike mist, am I correct?

[Steve Noble]

49 minutes ago, luftmodels said:

Thank you so much for your tips. I already started to see little improvements. Does it matter how fast we move our hand? Something tells me I'm doing it too fast. Can it be an issue?

 

Basically you do 5-6 coats in total, don't you? A bit hard to grasp the concept of "light but wet coats of paint" . Basically this is 100% coverage unlike mist, am I correct?

Yes, kind of. I apply the paint so it goes on wet, but not heavy. Too heavy and it will run and cause problems, too light it will be dry. It's all well and good applying mist coats to build up the colour. But too many mist coats can leave the surface dry and rough. I find if I apply wet coats from the start, but light wet coats, I still get good coverage but the paint is smoother and never dry or rough. On the final coats I do apply the paint very wet, but again not so heavy/wet that the paint runs or sags. It's a fine balance between wet and heavy, the magic moment just before it runs, but doesn't actually run, will give you the best gloss finish straight from the airbrush. Many people apply the paint just too dry and they end up with a rough surface and the dreaded orange peel texture..

[luftmodels]

2 hours ago, Steve Noble said:

Yes, kind of. I apply the paint so it goes on wet, but not heavy. Too heavy and it will run and cause problems, too light it will be dry. It's all well and good applying mist coats to build up the colour. But too many mist coats can leave the surface dry and rough. I find if I apply wet coats from the start, but light wet coats, I still get good coverage but the paint is smoother and never dry or rough. On the final coats I do apply the paint very wet, but again not so heavy/wet that the paint runs or sags. It's a fine balance between wet and heavy, the magic moment just before it runs, but doesn't actually run, will give you the best gloss finish straight from the airbrush. Many people apply the paint just too dry and they end up with a rough surface and the dreaded orange peel texture..

Got it. I really appreciate your detailed answer. I will continue my practice on spoons. Funny fact that I almost always get nice results on spoons because I don't really care and when I work on a model and care a lot... well.. I tend to screw it up. 😁

[Space Ranger]

I concur with all of the above. If you are getting a rough surface like sandpaper, that means either (1) your air pressure is too high or (2) you're spraying from too far away, causing the paint to dry before it reaches the model or (3) your airbrush nozzle is open too much and your spray pattern is too wide, or (4) a combination of some or all of the above. I have found. too, that good visibility and adequate lighting is necessary to see that the paint is going on wet, and that viewing the model from several different angles as you spray helps to better see the light reflections that indicate a wet coat. Experimentation and practice will help you find the right combination of these factors.

 

Paul Budzik's Scale Model Workshop channel on YouTube has several videos on airbrushes and airbrushing, and I encourage you to view them. They offer much useful advice. Paul is one of the best model builders/model engineers I know.
https://youtu.be/C3Dya_cWxpU

 

 

And now, please bow your heads. Let us spray.

[dnl42]

1 hour ago, Space Ranger said:

If you are getting a rough surface like sandpaper, that means either (1) your air pressure is too high or (2) you're spraying from too far away, causing the paint to dry before it reaches the model or (3) your airbrush nozzle is open too much and your spray pattern is too wide, or (4) a combination of some or all of the above. I have found. too, that good visibility and adequate lighting is necessary to see that the paint is going on wet, and that viewing the model from several different angles as you spray helps to better see the light reflections that indicate a wet coat. Experimentation and practice will help you find the right combination of these factors.

I just wanted to repeat this. If you're getting a rough surface, something is wrong.

[luftmodels]

2 hours ago, Space Ranger said:

I concur with all of the above. If you are getting a rough surface like sandpaper, that means either (1) your air pressure is too high or (2) you're spraying from too far away, causing the paint to dry before it reaches the model or (3) your airbrush nozzle is open too much and your spray pattern is too wide, or (4) a combination of some or all of the above. I have found. too, that good visibility and adequate lighting is necessary to see that the paint is going on wet, and that viewing the model from several different angles as you spray helps to better see the light reflections that indicate a wet coat. Experimentation and practice will help you find the right combination of these factors.

 

Paul Budzik's Scale Model Workshop channel on YouTube has several videos on airbrushes and airbrushing, and I encourage you to view them. They offer much useful advice. Paul is one of the best model builders/model engineers I know.
https://youtu.be/C3Dya_cWxpU

 

 

And now, please bow your heads. Let us spray.

How can I open nozzle too much? It is quite fixed unless I remove the tiny cap (which I do for small parts). I'm afraid I did spray far away and too wide. I will work on improving this part. Thank you!

 

Paul is great modeler. I do like his videos very much. He presents his topics in simple manner and nonetheless very informative. I watched his decals application video and learned some tricks too. Thank you!

[Space Ranger]

8 hours ago, luftmodels said:

How can I open nozzle too much? It is quite fixed unless I remove the tiny cap (which I do for small parts). I'm afraid I did spray far away and too wide. I will work on improving this part. Thank you!

By "open nozzle too much" I meant moving the needle back to widen the spray pattern, whether by pulling the trigger back too far (in the case of a double-action airbrush) or by turning the air adjustment knob too far counter-clockwise (if a single-action airbrush).

[luftmodels]

1 hour ago, Space Ranger said:

By "open nozzle too much" I meant moving the needle back to widen the spray pattern, whether by pulling the trigger back too far (in the case of a double-action airbrush) or by turning the air adjustment knob too far counter-clockwise (if a single-action airbrush).

Ah, I see now. I always thought that I have to pull it all the way (double-action) for large areas since the pressure has been set. If we pull the lever less, then we don't get our preset pressure output from the compressor. However, this doesn't apply for small parts.

[Space Ranger]

2 minutes ago, luftmodels said:

Ah, I see now. I always thought that I have to pull it all the way (double-action) for large areas since the pressure has been set. If we pull the lever less, then we don't get our preset pressure output from the compressor. However, this doesn't apply for small parts.

You don't have to pull it all the way for large areas. If you pull it less, your spray pattern will be smaller. It will therefore take you longer to spray a large area, but you will have more control. And in the case of a scale model, that time difference is negligible, unless of course the model is, say, a 1/32nd scale B-17 or something similar!

[dnl42]

I never fully open the paint flow except when pointed away from the model, to "cough" the airbrush. 

 

I do use a 0.5mm nozzle for primer, base color, metallic,and clear coats on my models, which are primarily 1/48 aircraft. I use a 0.3mm nozzle for small parts and detail painting. 

[luftmodels]

1 hour ago, Space Ranger said:

You don't have to pull it all the way for large areas. If you pull it less, your spray pattern will be smaller. It will therefore take you longer to spray a large area, but you will have more control.

Well, I guess I learnt something new today. I thought that I lose psi if I don't open it fully. Thank you for busting my myths. 👏🏻

 

19 minutes ago, dnl42 said:

I do use a 0.5mm nozzle for primer, base color, metallic,and clear coats on my models, which are primarily 1/48 aircraft. I use a 0.3mm nozzle for small parts and detail painting. 

 What is the benefit of 0.5mm for metallic? Usually metallic particles are very fine.

[dnl42]

10 minutes ago, luftmodels said:

What is the benefit of 0.5mm for metallic? Usually metallic particles are very fine.

I find I'm more likely to need to cough the 0.3mm nozzle when spraying metallics.

[luftmodels]

1 minute ago, dnl42 said:

I find I'm more likely to need to cough the 0.3mm nozzle when spraying metallics.

This is interesting but I have nothing to compare to since I have 0.3 only. But I don't think this is so critical. 😀

[Space Ranger]

8 hours ago, luftmodels said:

Well, I guess I learnt something new today. I thought that I lose psi if I don't open it fully. Thank you for busting my myths. 👏🏻

In fact, the pressure should increase, albeit slightly, because your compressor is pushing the same volume of air through a smaller orifice.