Dilbert reflection in shiny black paint

Anybody can spray a can of paint, and anybody can get a dull spotty paint job that flakes off at the slightest touch. But with just a few extra supplies, extra preparation, and time and work it is possible to achieve a very nice paint job with a finish so mirror-like that you can easily see your reflection. For another example of what can be achieved view the pictures of my Pink-n-Purple case mod project.

This can be time consuming, but the result is well worth the effort. What I am about to describe may sound like a lot of steps. They are all necessary if you want a very polished mirror like finish. This can be done with minimal tools or facilities and just normal paint. I do recognize that professional painters such as those in the automotive industry will view this as simplistic. But anybody can do what I've done here without needing lots of expensive equipment and without handling expensive and highly toxic professional automotive paints.

Materials

You will need a small supply of relatively cheap tools and materials. The most important though is time and patience...it can easily take a week or longer to paint one surface. Anyway the materials list:

  • 2 cans of sandable primer (grey automotive primer works best)
  • 2 cans of lacquer-based gloss paint of your color (dark is best)
  • 1 can clear enamel (optional)
  • wet-dry sandpaper, grit sizes 320, 400, 600, 1000 (and optionally 1500 and 2000 grit).
  • sanding block
  • rubbing compoung
  • polishing cream/paste (not wax)
  • denatured alcohol and/or tack cloth
  • clean cotton rags and lots of paper towels
  • plastic watertight shoebox-sized container
  • drop cloth
  • latex gloves (optional)
  • ventilation mask rated for paint fumes (not "dust" mask)

Depending on the size of your case you may be able to get by with fewer cans. For the best results you will be applying two coats of primer, at least two coats of color, and optionally a final clear enamel coat.

Note: I'm assuming you're painting a metal surface such as steel or aluminum. If you're painting plastic you should use specially formulated Plastic Primer instead (such as from Rustolem).

Update: since first writing this, steel cases have pretty much given way to plastic cases. If so, you will not need to do nearly as much sanding with plastic, and use a light touch. Also use primers specially designed for plastic surfaces.

For best mirror-like results you should use lacquer-based paint. Most gloss spray paint if not otherwise labeled is probably lacquer. Enamel or acrylic paints can be used but won't be as shiny. Also for mirror finishes stay away from any specialty paints such as textured, metalic, rusty-metal, etc. You may choose any color you want, but the darker the color the more mirror-like. Use black if you want the best possible finish. I recommend the Rustoleum(R) or Plasti-Cote(R) brands. There is a noticible difference in paint qualities, so stay away from the generic cheap stuff. Note you can also go up to very expensive automotive paints, but unless you have a lot of skill and specialy tools stick with the spray-cans.

Another important task is selecting the proper sandpaper. Don't use the tan-colored sandpaper designed for wood. You need to get the dark-grey sandpaper designed for metal; and specifically sandpaper labeled as being Wet-Dry. This sandpaper will not break apart when wet, and this is important because we will be wet-sanding. You will want a variety of grit sizes, ranging from the courser 320 or so up to a fine grit of 1000 (you may also go up to 1500 and even 2000 if you really want to put in extra effort). Usually the best place to find a wide variety of sandpaper in all the grit sizes is an automotive parts/supply store.

You will also want rubbing compound (liquid) and polish. Rubbing compound is roughly equivalent to 2000-grit sandpaper, and is absolutely necessary. Both can be found in automotive supply stores. Note that polish is not the same thing as a wax or other water-repelant coatings; it will be labeled just polish. It may come in either liquid or paste form; I prefer the paste.

Initial wet-sanding

Like most good paint jobs, the preparation stage is absolutely important and the most time consuming. And the first step is sanding. Usually you will be starting with a steel case (most cheap cases are steel) with a factory applied textured plain beige finish. The first step is to sand off almost all the finish down to the metal.

Update: if you have a plastic case, most of this section can be greatly simplified. You basically just want to sand enough to remove any of the texture on the plastic. Sanding metal cases on the other hand is much more laborious.

You may be working with an aluminum case instead. The only difference is that it is likely to have an anodized finish which is implanted directly into the metal rather than a more traditional paint layer. The anodized surface may be very hard and difficult to sand away; but since it is also likely to be very smooth it's not important to sand it down to just plain shiny aluminum.

Be forewarned, you will make a big mess. Take all the panels apart as much as possible. Fill the plastic container with an inch or so of clean water. You may want to put a few drops of dishsoap in it (not too much). This helps break the surface tension and provides just a bit of lubrication; remember you're sanding, not washing. Put a strip of the 320 course-grained sandpaper in the sanding block.

Always use the sanding block when possible. Do not use an electric sander. And do not hold the sandpaper by your hands or fingers, except for curved areas such as around handles or stamped indentions. Aside from removing the old paint, your primary objective is to get the surface as flat as possible. Smooth is not enough, it must be flat. And the areas most likely to be unflat are those around the edges and around any stamped depressions like door handles or grips.

When sanding you want to keep the surface and your sandpaper fairly wet. Occasionally "rinse" the residue off the sandpaper by dipping it in the water. If the surface gets especially dirty or gritty with residue, wipe it down and then wet it again and continue. If you've never wet-sanded before, the purpose of the water is two-fold. First it prevents fine dust from becoming airborne. Secondly it helps lubricate and wash the residue away, preventing the sandspaper from getting clogged. And as the paper and metal surface stay cleaner, you also get a smoother result with fewer scratches.

At this initial stage you can sand in any pattern that seems to work. But always try to keep the sanding block flat; don't put uneven pressure on a corner for instance. In later stages after we've applied some new paint, you'll eventually want to stick strictly with a back and forth linear motion with long strokes, avoiding any circular or haphazard patterns. Areas where the sanding block can't reach will have to be done by hand as best as possible.

Continue wet sanding until almost all the paint is gone. It's not terribly important to have only bare metal showing. You are only trying to get a very smooth and very flat surface, and a little old paint will not degrade your result. Note that the areas around the edges or any stamped depressions like door handles may require lots of sanding, as the metal is usually quite warped and distorted from true flatness due to the stamping process during manufacture.

Priming

Priming is very important--do not be tempted to skip this step. The primer layer bonds much more tightly to the bare metal surface than paint will. Without primer, paint will over time tend to flake off or bubble up. Also the primer allows you to get an even smoother and flatter subsurface to lay the paint upon.

Update: if you have a plastic case be sure to use a primer that is formulated for plastic; a so-called "plastic primer". These are fairly easy to find these days.

Before spraying any layer of primer or paint, you always need to have a perfectly clean surface. You don't want any sand-residue, dust, or even fingerprints or skin oils on the surface. You can use a clean lint-free cloth with some denatured alcohol to wipe the surface (denatured alcohol evaparates completely without leaving any residue). Gently wipe the surface, don't scrub it. You can also use a tack cloth (specially-formulated sticky cheese-cloth), to remove particulates, but it may not remove skin oils.

Don't use denatured alcohol on your final polished paint layer, as it will disolve a microscopic portion of the paint leaving a hazed or cloudy surface. But it's perfect to clean all the intermediate layers.

Safety note: only spray in well ventilated areas; preferably outdoors if conditions are suitable. You should also wear a ventilation mask that is rated suitable for paint fumes (ordinary dust masks do nothing for smaller paint-sized particulates and toxic gasses).

Completely spray the surface with primer. You want to use long even straight strokes. Keep the can about eight inches away and move at a very steady pace, not too fast and not too slow. Do not stop, or start, or reverse directions while the can is aimed at the surface. Each stroke should go the full width of the sheet, and each pass should overlap the previous slightly. Don't forget the edges of the metal. Reshake the can after every two or three passes.

You will likely see some banding patterns in the paint, and that's okay. You defintely do not want any thick puddling or drips, and definitely no drops or splatters. (If you ever get a drop of paint, it will be very noticible in your final surface, and will be almost impossible to sand out without going down to your bottom-most layer.)

Update tip: if using a typical spray can, be careful of drips caused by paint puddling up around the spray nozzel. It is best if you can spray horizontally or in a way such that the can is not directly over top of the surface you're painting. Or keep a paper towel wrapped around the can to catch the pooling paint.

Let the first primer layer dry completely (about 20 minutes, or according to the can's directions). Then you want to apply a light wet sanding, moving up to 450 grit or so. You may find some unflat areas which sand down to bare metal again, and if so just keep sanding. But remember you are trying to get a flat surface again, not remove all the primer you just sprayed on.

Then wipe, dry and clean the surface and lay down a second primer coat. You may want to make your painting strokes in a perpendicular direction to your previous layer to help hide the banding effect and get a more even covering.

Let the new primer coat dry and then wet sand again. If you work down to bare metal again don't worry about it. It's better to make it flat now then after you start applying color. Keep adding new primer coats (sanding between each) until you no longer work down to bare metal.

Painting, applying the color

You're now ready to start applying some color. The process will be very similar to that of priming. It's best to do this in a warm area, perhaps even outdoors under the sun if possible. The extra heat during the first few minutes while the paint dries will help the paint flow and settle into a smoother coat. After it starts to set and harden you can take it out of the sun so you don't over cook it. But even if you don't have a warm sunny day you can still get good results.

If possible lay the surface down so it is horizontal. Then, just like priming, you want to use straight and very steady painting strokes. Do not just wiggle the can all over the place. Also do not apply heavy coats. Three or even four light coats is much better than one heavy sloppy one. And whatever you do avoid touching the painted surface while it is wet, unless you just love sanding and starting over.

There are a few of extra things to be aware of while applying your color coats. First, shake up the cans well. And reshake them every few strokes. Failing to do so may result in an uneven color, and may also increase the likelyhood of getting splatters, at least from my experience.

Speaking of splattering, when using a plain old spray can (and not expensive automotive air guns), the spray will not be even. Common problems include splatters, drops, and overspray dust. Many of these problems can be avoided just through practice. If you don't have much spray painting experience, take a piece of cardboard and cheap paint and practice. Some of the techniques which I've found that help include keeping steady pressure on the spray button, keeping the can in a nearly upright position, shaking the can frequently between strokes, and nevery starting or stopping the spray while over your piece. Also to help avoid overspray dust, it helps to spray in horizontal bands left to right (or right to left), but starting at the edge closest to you and proceeding towards the far edge on subsequent strokes. But be very careful about holding the can directly above your piece, as you can get paint drops. Just keep your finger out of the spray and watch for pooling paint near the nozzle and you should be fine.

One final note about laying down your color: orange peel. Thats a term used to describe the texture that paint sometimes takes when drying, where up close the surface actually looks much like the skin of an orange. Orange peeling is almost inevitible unless you use professional equipment and paints. However, you want to try to avoid it as much as possible as that just means more work during subsequent sanding and polishing. I've found that orange peeling tends to occur more frequently if you are applying the paint too thickly; use lighter coats. You also can get orange peeling if your surface is not properly primed and cleaned.

Between each paint layer you should do a light wet sanding. You'll probably want to move up to at least 600 grit paper or even finer finer. During each sanding you should be trying to remove all paint imperfections, as well as sanding through any orange peel until the paint surface is smooth. If you prepared the primer layers well the surface should already be flat. However if you ever sand through the color and into your primer layer, stop. You don't want to sand down to bare metal unless you're prepared to prime again (you can actually cheat as long as the exposed metal area is pretty small). One difference when sanding the paint layers is that you should avoid any circular-style patterns. Strictly use horizontal or vertical sanding strokes, with light pressure.

How do you know how many coats to apply? Basically after you've sanded each coat and cleaned it, examine what you have. If You still see significant color differences or banding you need to keep going. Let each coat dry completely before applying the next! Yes, that can mean waiting several hours, if not to the next day. Paitence will pay off; rushing will not. Apply alternating coats in perpendicular directions.

When you finally get a coat that appears uniform you should then apply at least one more coat. This will insure that you have a thick enough good coverage to allow you to polish it.

Polishing

After you apply your final coat you should let it dry very well before touching it; consider waiting until the next day. Then you'll want to wet sand it too, but start at 1000 grit paper. Never sand with swirling patterns and try to be delicate. Your do not want to introduce any excess scratches at all. You should definitely not have any remaining imperfections such as orange peeling. If you are willing to put in extra effort, you can also resand with 1500 grit and then finally 2000 grit paper. Those finest grit sizes will remove very miniscule amounts of paint. Basically they are just removing the fine scratches made by the previous grit paper.

The paint surface should now be very smooth and uniform with only microscopic scratches, but perhaps a little dull. Clean the surface with water and a soft cloth, but do not use an cleaning fluids like alcohol. You are now ready to polish.

Take a clean cotton cloth and apply some rubbing compound. Then just start rubbing it against the paint surface. You don't need to scrub very hard, and in fact use care or you could actually rub the paint away. You will see some of the paint color rubbing off onto your cloth. Regularly wipe away the compound with a clean part of the rag and examine your progress. The paint should start to get shiny. Continue polishing, trying to produce a uniform and consistent surface. This step takes a LOT of time and muscle and patience. But this is the step which finally starts to pay off, the resulting surface should be very shiny and you should start to see reflections in it.

As a final step you will want to polish it. The rubbing compound should have removed all the microscopic scratches, but the polishing stage will add just a bit more shine and clarity in the reflections. Polishing doesn't require nearly as much effort as the rubbing compound, but it's still a hand process. Use a clean soft cloth again and just rub the polishing paste against the paint. Again you'll see a bit of color transfering onto your cloth. Use gentle strokes. The end result should be a very mirror-like surface. Clean it all up with water and a clean soft lint-free rag.

Clear coating and waxing

If you used a lacquer-based paint, you may optionally decide to apply a final hard clear coat. This will give the surface more durability than the soft easily scratched lacquer. However it will also result in a slight loss of glossiness, so you may decide not to do it if your case is not subject to wear.

The clear coat is simply a layer of clear enamel paint layed on top. You should always test the clear coat and your paint for compatibility on a scrap piece first to make sure you don't get bubbling or other chemical reaction (sticking with the same brand usually avoids most trouble). You will paint on the enamle just like you did the final color coat. It may take one or two coats, but try to avoid any more or your shine and color will loose some of its luster. Also note that enamel can sometimes take longer to dry than lacquers, so read the labels.

You also want to apply rubbing compound and polish to the clear coat as well. If you've polished the underlying color coats then you shouldn't need to do as much work to the clear coat...just enough to return the shine. This time however pay attention to your cloth; if you start to get paint color on it you know you've rubbed through the clear coat. Stop and apply another layer.

About waxes: You may optionally apply a wax or similar surface sealant as a final step, just like you would a car. However you should not apply anything for one to two months! Although the paint may be hard and appear dry, it will actually take it that long to fully cure. Only after that should you apply waxes.