Using Poster Tack as a Masking Medium
by Lee Rouse


There are many ways to airbrush an aircraft camouflage scheme. For example, you can use paper masks, enlarged and cut out from the kit instruction sheet. Then there are masking tape masks, Parafilm masks, liquid masks and even (gasp) the free-hand airbrushing approach. One of the more recently discussed methods involves the use of poster tack. Poster tack goes by a lot of different names, and its quality and characteristics can vary from brand to brand. It's been around for a long time too. In fact, I recall my 6th grade teacher using the stuff to put class art on the wall way back in 1966.

So what is poster tack? Although I haven't been able to locate a source that can give me specific ingredients, I think it's safe to say that poster tack is a synthetic rubber compound without hazardous properties under normal conditions (i.e., don't go lighting the stuff and sniffing the fumes!). It should be stored in a cool location away from sunlight or sources of heat. It can be torn apart and rolled like clay, but maintains strong elastic qualities if pulled. Rolling the material until warm makes poster tack more pliable and flexible.

As I've said, not all poster tack is alike. It can vary considerably in its hardness, elasticity, stickiness, oiliness, and color, to name a few properties. I've found that some kinds definitely work better than others. My first suggestion is to stay away from the colored brands. I learned that the hard way several years ago. I was using a blue colored poster tack called Tac'N Stik by Ross. I stuffed it into a wheel well, painted the underside of the aircraft, then pulled it out a week later. Some of the blue dye in the Tac'N Stik had leached into the wheel well, staining my interior green color. Another brand to stay away from is the one sold by my local Staples office supply. This tack is white, so there is no problem with color leaching. However, it is almost as sticky and elastic as chewing gum, making it very difficult to remove. Most recently, I've come across a brand simply called Poster Putty. It comes in a 2-ounce package, which I found in the school supply section of the local WalMart. I've found this putty to be elastic, but not too sticky. It's very easy to shape and relatively easy to remove. Late breaking news - I looked for this brand at WalMart today. Apparently it's been replaced by a different type that's light blue in color. Bottom line - shop around, pick up a couple of different brands, and try each of them until you find one that works well for you.

So, enough about Poster Putty and its cousins. Let's talk about how I use it to mask for aircraft camouflage.

Assuming that you have laid down the undersurface color, masked that off, and laid down the first topside camo color, you are ready to begin masking. The first thing you will want to do is to carefully study your reference material, typically the kit instructions to see how the camo pattern lays. Roll out a small piece of Poster Putty into a snake. It must be long enough to cover the length of the camo line you are replicating. Varying the diameter of your snake will affect how soft the camo demarcation line is- a fatter snake (say inch diameter), will give you a softer demarcation.

For my Brewster Buffalo, I decided that I would like a relatively sharp demarcation line. Therefore, I rolled my snakes out in rather thin pieces, about 1/8 inch in diameter. Each piece is then laid down along the edge of the color line. It is important to hold your airbrush perpendicular to the surface you are spraying. It also helps to use a low pressure setting (around 15 psi), which will help prevent paint from depositing unevenly under the edge of the snake. One other suggestion, if you need to make slight changes in the position of the snake, wet your finger or a toothpick with water. Otherwise the snake will stick to whatever you are prodding it with.

Once you have your perimeters laid out you must mask off the part that will remain the first camo color. There are a number of ways to do this. For example, you can use more poster putty to fill in the areas between the snakes, thus masking off the 1st camo color. I hit upon the idea of using common household plastic wrap (Handiwrap, Saranwrap, etc.) as a mask. It's really very simple. Cut out a piece of wrap that is slightly larger than the area you want to cover. Lay the wrap directly onto the poster tack snakes and gently press it along its length to be sure it sticks.

Now you need to get rid of the excess wrap. Take a new #11 blade, and press slightly into the snake until you cut through the wrap. Then draw a line with the point of the blade along the length of the snake, separating the excess wrap. This can part can be a little finicky since you are pressing against the soft surface of the snake. Take your time and DO use a NEW #11 blade. Next, airbrush your second color. Finally, remove the snake and wrap. The snake should come up without any difficulty. If you have any "Kling-ons", use a small ball of Poster Putty, press against and lift them away. You may also find that the area where the snake has been laid has a slightly glossy appearance, which look noticeably different if your first camo color is a flat paint. Don't worry, once you put on your clear coat for decaling, that gloss will blend right in.

The result of your efforts should be a uniformly feathered edge. If you have any areas which turned out a little ragged, simply spread out a piece of Poster Tack along the edge and airbrush the offending edge.

That's all there is to it. Try this technique and see what you think. If you have any comments, or ideas for further refining my approach, please feel free to email me.