Masking Canopies Using Bare Metal Foil

by Dave Sherrill

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Masking canopies would not be at the top of most modelers “fun to do” list. What I want to demonstrate in this article is that masking canopies does not have to be a laborious or dreaded phase of model building. By using Bare-Metal Foil (BMF) you can actually mask and paint most canopies with very good results in a short amount of time. For demonstration purposes I’m using the “greenhouse” canopy from Hasegawa’s excellent 1/48 C6N1 Saiun kit. Because of its size, it fills the camera frame and would most likely be regarded as a drudgery to mask. There are 20 separate frames just on the canopy piece; however, it took me under an hour to apply the foil, burnish, cut, remove the excess foil, and prepare it to paint.

The first step to a successful masking project using BMF is to dip your canopy in that miracle modeling elixir known as Johnson’s Future, or Kleer. Dipping in Future has several essential benefits. Your paint will adhere better, clarity will improve, and the amount of residue that BMF is notorious for leaving behind will be minimal.

I start the dipping process by holding the canopy at the tip of one end with a pair of self-locking tweezers. Next, I dip the canopy in a small narrow jar filled with Future and hold it under for a few seconds. I then lift it out and tap some of the excess off on the edge of the jar. Using a soft #4 artist’s brush, I brush or wick away any excess Future that has settled to the edges and corners of the canopy. This is a very important step in the process. If left to dry, excess pooling of Future can cover the contours or recessed lines of the framing and you will not be able to burnish the details needed to guide your cuts. I allow the canopy to dry overnight in an empty Altoids tin with some holes drilled in the sides. If you feel you need to redo your dipping effort, a short soak in some household ammonia followed by a wash in warm soapy water and wiped dry with a soft cotton cloth should have you ready for another try. Here’s a photo of the canopy with a coat of Future applied. I dropped my first attempt on the floor and had to start over.

So now your canopy is Future’d and you’re ready to start masking. There are several different types of BMF such as Black Chrome, Ultra Brite Chrome, Matte Aluminum, etc. But the only one to use in my opinion is simple Chrome. I’ve tried some of the others and they just don’t seem thin enough; even cutting them with a new scalpel blade often caused jagged tears. They also left a lot of residue.

I photographed some of what I consider to be highly essential tools for masking with BMF: a burnishing tool, a #11 scalpel, a pair of needle-nose tweezers, and a sharp pointed toothpick.

Start the masking by cutting a section of BMF that covers the canopy. Depending on the shape of the canopy you might be able to cover it all with just one piece. With bubble tops and windscreens it usually requires more than one piece for a smooth surface. A little wrinkling is inevitable, but you don’t want big ridges. In this instance I was able to get by with one piece, and I did an initial burnishing with my fingers and burnishing tool. To really bring out all the detail, I ran the toothpick into all of the corners, edges, and crevices. I’ve found that Hasegawa canopies have recessed lines to simulate the framing, and Tamiya canopies have raised edges. Both work well as guides for cutting the BMF.

Once all the detail has been thoroughly burnished and you can see all the framing, it’s time to start cutting. I like to use a #11 scalpel blade, but a #11 X-acto will work as well. You’ll want to use only light pressure to cut around the frames. When cutting raised framing, you’ll want to apply slight pressure not only downward but towards the framing as well. It doesn’t take much pressure to cut through the BMF. I wear close-up reading glasses under good lighting for this part of the process. I’ve masked a lot of canopies but have never made any serious slips and ruined a canopy. I think the key to this is being methodical and using only light pressure on the blade. With its recessed frame lines the Hasegawa canopy was very easy and simple to cut. The blade stayed right in the groove. The rounded corners of the framing were a bit tricky, but I found that placing the blade on its tip and going slowly to be the best method for this kind of cut.

If you’ve cut all the edges of the framework it will be easy to lift off the excess.

If you make a slight error, re-masking and re-cutting with a small patch of BMF is easy to do. Once the entire framework is exposed and you’re satisfied with your work you should gently wash the canopy in some warm soapy water and dry with a soft cloth to get rid of any skin oil that might have been left by all the handling. If you’re going to paint your canopy in place, now’s the time to glue it on the model.

I generally use Tamiya acrylics for model painting, and in this case I used their Japanese Navy cockpit color (XF-71) as the first coat. That way, when I finish painting, the interior of the canopy has the lighter cockpit color showing. When that coat was dry, I airbrushed a coat of Tamiya’s Japanese Navy Green (XF-11). After that was dry I applied a thorough coat of Testor’s Dullcote. I like to paint my models and canopies whether separate or attached at the same time, and with all the same clear coats. That way my canopy framing and fuselage match in color tonality.

If there’s a fun part to all of this, it might be at the stage of the process where the masking is removed. This is where my scalpel and needle-nose tweezers really come into play. No matter how many days I’ve left the masking on (and I know some of you out there reading this might not believe me), I’m generally able to pull off the masks in one piece. Carefully use the tip of the scalpel to lift an edge of the mask. Once you have a small flap lifted, use the tweezers to gently pull off the rest of the mask.

Click the thumbnails below to view larger images:

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Using this method, I have not yet marred the surface of any canopy. It’s just a matter of using light pressure and taking your time. I can’t stress enough the importance of using needle-nose tweezers in this process. There’s no other substitute for grasping the little flaps or small slivers of BMF. To avoid the paint chipping that sometimes occurs when removing the masks, you might want to consider running your blade around the framing one more time before lifting the mask. I didn’t in this case, and I only had one small chip that was easy to touch up. I placed a small piece of BMF over the chip, burnished, made a cut along the frame and gave it some paint on a fine-tipped brush. I’ve had very few problems with chipping if I make sure to dip with Future and to not pull the masking back over an edge. Always pull the masking away from or along the frame edge.

The final step is to clean any residue from the BMF that’s left on the previously masked surfaces. For this I used a Q-tip bud lightly dampened with WD-40. The WD-40 cleans the residue very quickly. Lastly, I gave the canopy a wiping with a soft cotton cloth to remove the WD-40 and polish the surface. Personally, as long as I cover my painted canopy with a clear coat of Dullcote I have not experienced any paint removal, discoloration, or marring using WD-40.

To judge the safety of using WD-40 on painted surfaces I tested WD-40 on unprotected Tamiya acrylic and Testors enamel painted on some scrap plastic. After some hard rubbing I got a very faint color removal of the acrylic paint. A light rubbing however, was all it took for a complete removal of the enamel. A citrus solvent product called Goo Gone can also be used to remove residue. I tested Goo Gone on the same unprotected painted surfaces and got the same results. Both Goo Gone and WD-40 dissolved the unprotected enamel paint. They do not however; seem to have any adverse effect on clear acrylic or clear lacquered surfaces.

Above is a photo of the final result. Whatever jaggedness you might see on the edges has more to do with the lighting and pixel count than how it actually appears.

In conclusion, this is a process that has worked for me. Everything I’ve written is based on my experience. Your results may differ. If you’re interested in improving your masking results I encourage you to give this technique a try. The best way to begin is to test it out entirely on a spare canopy before you actually try it on your latest project. BMF, I should add, is also excellent for masking wheels. If you have any questions or want to correspond about this article you can reach me at davesher49@comcast.net
 

Text & Images Copyright © 2005 by Dave Sherrill
Page Created 20 September, 2005
Last Updated 19 September, 2005

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