Dave Porter, Customer and Tech Support at The Bonneville Shop
There are 4 basic steps on how to apply a waterslide decal:
1. Surface Preparation
“The preparation prior to decal application cannot be overstated.”
One important detail when addressing the finish on a motorcycle restoration is the application of decals to painted surfaces. There are “peel and stick” Mylar stickers, die-cut transfers, varnish-on decals, “dry-fix”, and waterslide decals available today. The majority of the decals offered in our catalog are now of the waterslide variety.
All of the various types of decals and stickers have one thing in common- the surface being covered with the decal must be clean, dry, and free of any wax, polish, or oil. If you casually slap a peel and stick Minimum Oil Level on your freshly painted oil tank and a speck of dust is under the sticker, a pimple will result, prompting disappointment. The preparation prior to decal application cannot be overstated. A high quality tack cloth can be used to lightly swipe over the surface to remove any unwanted dust or lint.
2. Preparing the Decal
My experience with waterslide decals goes back many years, when my favorite hobby was building model cars. Those decals supplied with the model kits were waterslides, and I learned the technique quickly after ruining a few, with no prospects for obtaining replacements. New old stock decals can often be identified by a slight yellowing of the backing membrane that surrounds the script. Extra care must be taken with these relics, as they are often decades old.
The current decals supplied to the market are generally high quality reproductions, with a very clear membrane. Whether you are cutting a decal from an assortment sheet, or have an individual decal, you will want to trim around the script as closely as possible, so the footprint of the clear membrane is minimal, particularly if you are NOT planning to apply clear coat over the waterslide after it is applied. Once you have prepped the surface and have the decal trimmed to your satisfaction, you are ready to apply the waterslide decal.
Some restorers prefer to soak a clean cloth with water, then lay the decal on top of the cloth, so there is a wet surface underneath the backing paper. A spray bottle with lukewarm water is used to moisten the top of the decal. After 10 or 15 seconds, the decal will be saturated enough to start to lift from the backing paper. Once you can lightly slide the decal off the paper, you are ready to apply it to the surface.
I prefer to fill a small basin of lukewarm water about two inches deep, enough to dip and submerge the decal in the water for 5-10 seconds. With this method, you can hold onto the edge of the decal and will notice it lifting off of the paper. Since you are holding the border, you can lift the decal out of the water and gently place it on the panel, sliding the backing paper from under the film.
3. Applying the Decal
There will be more time to accurately place the decal to the desired location when it is well saturated, since it can be carefully slid on the panel several seconds before it sets up and starts to stick. There will be water and air bubbles present that can be blotted out with a clean lint-free cloth. If there is a stubborn air bubble that is difficult to remove from under the decal, a very careful application of warmth from a hair dryer can be used to dissipate the air bubble, although usually the undisturbed waterslide will dry perfectly overnight.
4. Finishing Coat
Once applied, the surface can be cleaned with water, dried with the lint-free cloth (I like using old cotton T-shirts as rags for this), then swiped with the tack cloth. You are now ready to apply the protective clear coat. I like using clear lacquer on most motorcycle applications and nitro cellulose clear coat for my guitar projects. The point of clearing over the decals is twofold: you are protecting the fragile ultra-thin film membrane, and also blending the border to the point where it looks like the decal was painted on.
Remember, common waterslide decals are usually cheap, so consider having an extra one on hand if you fail on your initial attempt. Take your time and have fun with it. Perfectly executing a decal application is very satisfying and the resulting detail on a restoration really represents the overall attention to detail.
