Mask/stencil questions

What are some "best practices" surrounding masking and stenciling when using rattle-can enamels on more complex paint jobs?

I'm aware of the trick of overcoating the mask with a light coat of the base color to seal the edges. However, I have a few questions regarding other issues surrounding multi-color paint jobs.

My questions:

1. What type of tape do you prefer for "bulk" masking?

2. How long do you allow the base coat to dry before applying tape or stencil masks?

3. How long do you wait for the top coat to dry before removing your masks?

What I've been doing:

1. Generally I've had good luck with blue painter's tape. However, I have had it lift the undercoat on a few occasions, or leave a texture from the adhesive on the undercoat. Lifting is a major bummer, but the texturing is usually not visible once clear coated. If it looks really bad I'll lightly wet sand with 800 grit and that takes care of it. Of course some of this may be related to #2. I've also recently picked up a roll of the purple low-tack tape ... seems promising, and I may switch to that.

2. Usually, I'll let the under coat dry for 30 minutes or so (until the paint is dry to the touch and can be handled gently) until I start masking for the second color. Generally this has been working fairly well for me with the exception of the issues mentioned above, and it typically keeps me within the recoat window of the under-coat.

3. I usually try to remove my masks as soon as the paint is no longer tacky. Of course, this is tricky, as you have to be VERY careful not to mar the new paint. In "bulk" masking situations, this generally has worked well for me, but it's a pain. However, finer details such as closely spaced stripes or lettering, I've definitely had issues where the top coat got pulled off in the tight sections. I've been doing it this way out of fear that a) the longer the tape sits, the more likely it is to damage the base coat, and b) I worry that if the topcoat is allowed to dry too much, it'll get stuck to the tape and peel or chip as it's removed. I've had some success scoring the tape lines with a sharp hobby knife before pulling the tape to deal with the detail issues, but it can be tedious, and also risks more "touching" if the top coat is still somewhat soft.

The bottom line:

I've very interested in what you more experienced modelers are doing. Slowly trying to up my painting game, but it's often difficult to find good advice on some of these details, and much of it is conflicting.

1: I use the green frog tape of varying widths for stripe type patterns. Seals well when burnished, and leaves no texture when removed. I also use Friskit masking film for large area coverage, or for intricate designs like flames that I can sketch out, cut, then apply in place.

2: The answer you won't like. For Rusto 2X enamel, I wait at least three days or longer depending on if the environmental conditions are suitable.

3: At least 24 hrs. paint is still slightly uncured so it seems to heal when removing the mask. *caveat* For a complex job where I want under layers to remain masked, I layer the mask material and remove it all 24 hrs after the last coat. I just pulled all the masking layers off my Hot-bird Phoenix (below) last night without issue being sure to pull the mask cleanly and perpendicularly to avoid flaking or peel. Just needs some touch up sanding of paint dams with fine grit paper.

My bottom line: Patience

Nytrunner said:

1: I use the green frog tape of varying widths for stripe type patterns. Seals well when burnished, and leaves no texture when removed. I also use Friskit masking film for large area coverage, or for intricate designs like flames that I can sketch out, cut, then apply in place.

2: The answer you won't like. For Rusto 2X enamel, I wait at least three days or longer depending on if the environmental conditions are suitable.

3: At least 24 hrs. paint is still slightly uncured so it seems to heal when removing the mask. *caveat* For a complex job where I want under layers to remain masked, I layer the mask material and remove it all 24 hrs after the last coat. I just pulled all the masking layers off my Hot-bird Phoenix (below) last night without issue being sure to pull the mask cleanly and perpendicularly to avoid flaking or peel. Just needs some touch up sanding of paint dams with fine grit paper.

My bottom line: Patience

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Nice. The closest I've come to "flames" is a fiery multi-color fade using Testor's enamels and a cheap single-stage airbrush.



I'm hoping to get into some more detailed and multi-layered paint schemes ... especially on larger rockets where there's a bit more canvas to play with.

Now an airbrush is something I should look into trying. (hard in an apartment)

I've heard there's much better control and dispersal pattern choice than you can achieve with spray cans. My intent on the Hot bird was to leave some color fade sections and blending, but the spray just coated it on the first pass

Nytrunner said:

Now an airbrush is something I should look into trying. (hard in an apartment)

I've heard there's much better control and dispersal pattern choice than you can achieve with spray cans. My intent on the Hot bird was to leave some color fade sections and blending, but the spray just coated it on the first pass

Click to expand...

Yeah, I need a better setup. I wanted to experiment with it so I got the cheap Testors airbrush set which uses "canned air". It works OK for what it is, but I really need to invest in a better dual-action airbrush and a proper compressor. The Testor's paints are pretty stinky when applied by airbrush ... I was seeing pink elephants after I finished painting that one shown above in my basement.

The Testor's airbrush doesn't offer a whole lot of control, it's a very simple one. It's OK for simple fades and stencil work but would be very challenging for the kind of detailed work you expect from an airbrush design. The spray pattern is meh and cannot be mechanically changed with different tips, etc... and you can only control paint flow via air volume. That's how all single-action airbrushes work, but better ones have better tips and a more predictable (and adjustable) spray pattern. A dual-action airbrush allows you to vary both airflow and paint flow which gives you great control over paint application ... can't wait to try one!

I'd like to try using Acrylics, as they are low-odor and don't require fresh air ventilation or petro-chemicals for cleanup/thinning. They are also a LOT cheaper than Testor's enamels, although you do thin the enamels down a LOT when spraying them, so that stretches them some.

I'm also considering making a DIY benchtop spray box that vents outside ... plenty of ideas for such a build on this forum and out on the web. It'd be useful for spraying any kind of paint, and allow me to paint any time I like instead of whenever the weather is amenable. ...and no more little insects embedded in my paint jobs!

Fades are definitely challenging with rattle cans ... just no meaningful control of paint volumes, but you can pull them off if your model is a bigger one, and are not too concerned about exactly where the fade begins and ends. Some graffiti artists out there could prove me wrong, but I ain't got those skillz with a paint bomb.

1. What type of tape do you prefer for "bulk" masking? I use Tamiya masking tape for fine masking, then blue tape overlapping to widen it a little bit. Then for bulk masking I use either slip it into the bag the kit came in or a few wraps of Saran Wrap

2. How long do you allow the base coat to dry before applying tape or stencil masks? Longer than needed, I usually try to wait days. I have in a rush waited hours. Check the instruction for the recoat window.

3. How long do you wait for the top coat to dry before removing your masks? Not very long. As soon as I can with out smearing the top coat.

beantownJPL said:

but I really need to invest in a better dual-action airbrush and a proper compressor. The Testor's paints are pretty stinky when applied by airbrush ...

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I use a pasche single action airbrush and Createx colors for 80% of my rockets. Minimal odor and lots of color choices. Single action is all I need. If you want to do free hand fades and whatnot you may benefit from dual action.

solid_fuel said:

1. What type of tape do you prefer for "bulk" masking? I use Tamiya masking tape for fine masking, then blue tape overlapping to widen it a little bit. Then for bulk masking I use either slip it into the bag the kit came in or a few wraps of Saran Wrap

2. How long do you allow the base coat to dry before applying tape or stencil masks? Longer than needed, I usually try to wait days. I have in a rush waited hours. Check the instruction for the recoat window.

3. How long do you wait for the top coat to dry before removing your masks? Not very long. As soon as I can with out smearing the top coat.

Click to expand...

1. Yeah, I do the same when really large areas need masking. Tape the line where the new color starts then use a bag, newspaper, whatever's handy. I find the bags that models come in are also useful for that purpose.

solid_fuel said:

I use a pasche single action airbrush and Createx colors for 80% of my rockets. Minimal odor and lots of color choices. Single action is all I need. If you want to do free hand fades and whatnot you may benefit from dual action.

Click to expand...

I did pick up a Paasche single-action at a garage sale (unused, still in sealed box), but haven't had a chance to use it yet. The adapter for the canned air cracked when I tried to use it, so I'll have to wait until I can spring for a compressor. All those parts look good, as does the needle, etc... So, I'll probably start with that and see how it goes before I dive into a dual-action. However, I've heard "3/4 oz Deluxe Airbrush Kit" at Harbor Freight is fairly well liked and rather inexpensive at $20.

How do you find the durability of acrylics vs. enamels? Anything one should know when switching from enamels to acrylics. I understand they're generally a lot more user-friendly.

I never used enamels in this airbrush. They do say try not to spray oil and water based paints through the same brush. But I find the acrylics to be very user friendly. Clean up is super easy. Warm water in the sink and some isopropyl alcohol for the really Gunked on stuff. I spray a 50/50 mix of water and 90% iso through it while I wait between coats. 10- 15 minute recoat time between coats of the same color is common. I would recommend a compressor with a tank. I use an old craftsman with a 20ish gallon tank. The durability is probably similar. I haven’t done any testing but I have had a few hard landings that didn’t cause too much damage.

solid_fuel said:

I never used enamels in this airbrush. They do say try not to spray oil and water based paints through the same brush. But I find the acrylics to be very user friendly. Clean up is super easy. Warm water in the sink and some isopropyl alcohol for the really Gunked on stuff. I spray a 50/50 mix of water and 90% iso through it while I wait between coats. 10- 15 minute recoat time between coats of the same color is common. I would recommend a compressor with a tank. I use an old craftsman with a 20ish gallon tank. The durability is probably similar. I haven’t done any testing but I have had a few hard landings that didn’t cause too much damage.

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You know ... at $4 - $7 a pop for rattle cans, the buyback period of switching to acrylics and getting a compressor wouldn't be too long. I'll have to see what I can dig up on craigslist.

Add to that the lack of noxious chemicals, a huge availability of colors... Color selection of rattle cans can definitely be a limiting factor sometimes.

I'm thinking this needs to happen soon...

That's a nice looking Hi-Flier.

I'm not a detailed finish guy, but since having moved to a place where there's no public land and I needed to join a club to fly, I've come to realize my paint jobs are middling to nice compared to a lot of what I see.

What I do:

1. Have no timeline.
2. Follow manufacturers recommended dry times for recoat.
3. Add a couple of days, depending on weather.
4. No masking fresh paint for at least three days.
5. Have no timeline.
6. When getting ready for second color (and so on) use either Tamiya or Delicate Surface Frog Tape and burnish the edges well.
7. Use cheaper tape overlapping the nice stuff to extend the mask, then add a third layer with paper or plastic shopping bags for mass area coverage (likely to change, plastic shopping bags are now illegal in my county and paper one cost money).
8. Pull the tape on the second layer (or third, fourth, whatever) as soon as you can after it won't run.

solid_fuel said:

1.

3. How long do you wait for the top coat to dry before removing your masks? Not very long. As soon as I can with out smearing the top coat.

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and when peeling the masks off, pull it back on itself at a slight angle away from the fresh paint.

beantownJPL said:

2. Usually, I'll let the under coat dry for 30 minutes or so (until the paint is dry to the touch and can be handled gently) until I start masking for the second color. Generally this has been working fairly well for me with the exception of the issues mentioned above, and it typically keeps me within the recoat window of the under-coat.

Click to expand...

The paint is just barely dry to the touch and you're putting tape on it?


If it's working well for you then more power to you, but I don't want tape touching my paint until it is pretty solidly cured, i.e. well on the other side of the recoat window.