Back on the Sprue: An O-2 Skymaster Story (Part 2)
Updated: Sep 8, 2020
In Part 1 of this series, I covered my initial foray back into the exciting world of modeling! It didn’t go smoothly, but ultimately, I was thrilled to be back doing something I used to love.
By the time Part 1 concluded, I had completed the main assembly and applied the base coats of paint. Now I was ready for what I thought would be the downhill task of decaling and weathering. If Part 1 generally featured problems related to my construction choices, Part 2 will highlight the need to further my understanding of modeling chemistry.
In what follows, I will share my experiences with “cloudy” decals along with a possible fix, my battle with an overly aggressive paint thinner, and how I learned to stop worrying and love the mistakes!
The Future of modeling
One of the tricks I remember reading about in FineScale Modeler many years ago was the use of Future floor polish (yes, floor polish, and before I forget, it's called Pledge Floor Gloss now) to seal the base coat of paint and lay down a smooth glossy surface for what's to come: decaling. For those just getting started with the hobby, let me briefly explain. The flat paints we have been using until now cure with a relatively rough surface which helps make them matte in appearance. If decals are applied straight on top of this rough surface, microscopic bubbles will form and lead to the dreaded effect we modelers call "silvering". Specifically, silvering is when the carrier film of a decal appears shiny under certain light conditions.
A common way to prevent silvering is to apply a clear gloss coat. Gloss paints, unlike their flat counterparts, dry with a smooth surface and this is precisely where Pledge comes in handy.
After applying a coat of Pledge to the model and waiting at least 48 hours for it to cure, I began the slow process of applying the decals one or two at a time. To help the decals conform to the model surface, I used Tamiya's Mark Fit and Mark Fit Strong decal setting solutions. That’s when the storm clouds gathered.
Today will be cloudy with a chance of tears
Somehow during the decaling process, a cloudy residue formed over the decals and surrounding paint. To this day, I am not sure if this was the result of an interaction between the Pledge and Mark Fit products, or maybe the Mark Fit products and old decals. I am also unsure why the cloudiness is absent from my photos; it was there, I promise! Frustratingly, my attempts to wipe away the cloudiness with water and cotton swabs were unsuccessful. My only thoughts were how sad it would be to have come this far only to ruin the model. In hindsight, this is a good time to share the following lesson: always test on scrap plastic or areas of a model that are not easily visible.
Reasoning that the cloudiness would magically disappear from an extended drying period, I pressed on and finished the decaling, said a quick prayer to the modeling gods, and gave the Skymaster a few days to dry.
A few days passed, and to the surprise of nobody, the cloudiness remained!
Not content with a cloudy Skymaster (the irony), I did what anybody does when something is ailing them: I consulted the Internet. Hours later, after some feverish searching, I came away astonished with what I had found. Nothing.
Then it hit me! What if Pledge was the answer this whole time? I already knew I had to apply another coat of Pledge to protect the decals from the weathering process to come. Maybe, just maybe, it would take the cloudiness away as well.
Today's forecast: acid rain sunshowers
The day had finally come to either lock in the cloudy decals or expel them with another coat of Pledge. To my delight, as I painted on the new coat of Pledge, the cloudiness on the decals started to magically disappear. Phew, I was rolling again.
The second coat of Pledge now dry, I began the first stage of weathering I had planned for this build: a "pin wash". A pin wash is a targeted wash meant to simulate grime in crevices and around raised details.
We can spend multiple posts on the topic of washes, but until then, here are the basic details of how things are supposed to work:
Seal the decals with an acrylic-based gloss coat (Pledge)
Apply an oil-based wash. I will be using Tamiya's Panel Liners—an enamel-based product—to crevices and raised details and allow it to partially dry
Use turpentine or mineral spirits and cotton tips to gently wipe away the excess
I proceeded as planned: step 1, check; step 2, check; step 3, fail.
Why the fail? Somewhere along the line in my hobby experience I have equated mineral spirits, turpentine, and paint thinner for the same thing, or at least being interchangeable. Reality check: they are not. You see, the simplified process outlined above is meant to alternate between layers of acrylics and oils/enamels which tend to be unreactive to one another. It turns out that the Testors Enamel Thinner I used to wipe away the enamel-based panel liner contains a chemical called n-propoxypropanol.
Because we aren't in chemistry class just know this: it is an alcohol and alcohol dissolves acrylics.
This sounds bad. What happened? I noticed that as I rubbed away the excess panel liner, the cotton tip started to feel tacky against the model surface. As the number of passes increased, cotton fibers began to get stuck on the model. I didn't know it yet but my choice of thinner was literally eating away my protective layer of Pledge. Things reached a crescendo when I made a cotton tip pass that finally disintegrated the wing; made a hole in my desk; and ate away the floor of my apartment! Kidding, But I did strip away some of the acrylic paint base coat down to the primer.
Unable to remove as much of the excess pin wash without also removing the base coat meant I was stuck. The end result was a dirtier plane than I wanted, and truthfully, it just looked sloppy.
Tamiya's Weathering Master to the rescue
One thing that every modeler must do from time to time is learn to stop worrying and love the mistakes. In this case, loving the mistakes meant I had to cast aside my vision of a relatively clean Skymaster for one that has had its share of action. For that I turned to Tamiya's Weathering Master color sets.
While these look like an everyday cosmetics beauty product, they are really a semi-wet pigment that can be applied to a model surface with either a sponge or a brush. The best part is that if you make a mistake you can always wipe away any excess and start over.
The underside received a hefty dose of mud and sand colors while a soot color was applied near the weapons and engine exhausts. The pin wash I was worried about earlier looks right at home now!
Thoughts and musings
This part of the build was supposed to be downhill and was anything but. While this can be frustrating in the moment, ultimately my interests are best served from gaining experience at this stage. After all, this is something of a "burner kit" and the intention is to get the mistakes out now.
On the decals specifically, I found it bizarre that the Internet had no explanation for the cloudiness I encountered. For now, just know that another coat of Pledge cleared up the problem. Ultimately, I would like to recreate the cloudy decals in the igluemodels.com laboratory and offer a more definitive solution to the community.
As it relates to the different solvents, turpentine, mineral spirits, and paint thinner, I will need to button up my understanding of when they are safe to use, especially when mixing between different brands. I was surprised that a common weathering process like a pin wash does not come with more Internet warnings about adverse reactions.
Finally, sometimes the model gods might just have it in for you. But don't despair, this is just a hobby, so learn to stop worrying and love the mistakes!
Stay tuned for the exciting conclusion of this build where I will cover the final detailing and give the Internet a walk-around of the finished product. Until then, it's time to let the paint dry!
Thanks for reading,
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