Spit Shine
(sans the spit)
Spit Shine (sans the spit)
While stainless steel is fairly simple to polish up since it fairs quite well in nasty conditions, aluminum is another issue. While aluminum does not rust, it does oxidize, making the surface dull. To combat this problem, manufacturers often coated aluminum trim parts with an anodized coating after being chemically polished with bright-dip, which is a solution of nitric and phosphoric acid. When aluminum is dipped in the solution, it becomes etched to metal and comes out with a shine like chrome that will last for many years. Eventually, this too will dull, leaving you to deal with the old coating, which can be a pain to get through. Without the anodizing, the aluminum will dull faster. This requires the occasional rub down using a product like EagleOne’s aluminum polish rags. It works great, but is time consuming. Zoop makes a product called Zoop Seal, and it is supposed to seal the aluminum from oxidizing for two years. We have not tried it, but it sounds good.
One quick and dirty method of removing the old clear anodizing is caustic soda. Sounds fun right? Well, it is not that bad. Your basic oven cleaner is made from caustic soda, that is why you are supposed to wear gloves and avoid the fumes when using it. You can simply place the parts in a tub (the shower will work, but your significant other may not like you doing this in the house, and it really smells bad…) and spray them with cheap oven cleaner, and let it soak for about an hour or so. It will turn a streaked gray color, and then you just hose it off with a high-pressure nozzle. You will have clean raw aluminum ready for polishing.
The polishing process is not that difficult, and there are easier ways. Purists would tell you to have the parts bright-dipped and anodized, but this is akin to the chroming process and it is not cheap, besides where is the fun in paying someone else to do it for you? You will need a few specific tools, but you already knew that. The standard polishing tools consist of buffing wheels, buffing compounds and a motor, but exactly which ones do you need? There are many different types of wheels and compounds available, all having specific purposes. Soft metals like aluminum and brass usually do not need the heavy cutting wheels (sisal) and hard-cutting compounds (emery) like stainless steel. Buffing plastics requires very soft wheels (string buff) and light action compounds (plastic compound). For most metals, the process involves several steps, starting with the rough stage. For aluminum, where you start depends on the initial condition of the metal. Clean, pit-free aluminum can be polished in two stages; spiral-sewn wheel with Tripoli compound finished up with a loose section buff and jeweler’s rouge or white rouge. If the part is severely oxidized, scratched and pitted, you likely need to start deeper than the standard spiral sewn wheel. In the case of the Ford Falcon center console we are working on here, the rear section has some serious pitting from either electrolysis or chemical corrosion. We had to step up the severity of the process.
To clean up the aluminum, we used a die grinder and three roloc finishing pads; a brown coarse pad, a red medium pad and a blue fine pad. Using the grinder, the aluminum was cleaned up, along with the anodizing, scratches and pitting. Once that was done, the buffing wheels were loaded up on the Eastwood 3\4 hp buffing motor and a series of buffing wheels (sisal, spiral sewn and loose section) along with emery, Tripoli and white rouge compounds worked the aluminum to a polished frenzy of blinding proportions. In other words, it got shiny.
This cool ribbed console came from an early Ford Falcon. It will look right at home in our ’63 Mercury Comet wagon project, but first it needs some TLC in the way of polishing. Kinda looks like a toaster.
The three aluminum trim sections were held on with welded studs through the body of the console. Disassembly was the first step.
Removing anodizing from aluminum requires either sanding or chemical stripping. This ’63 Corvair headlight ring was chemically stripped using heavy duty oven cleaner.
The finished products is raw aluminum. This polishes up quite easily if there is no heavy pitting or scratches.
Our console was not so lucky. The rear section had sat in water for a long time, allowing the chemical reaction to leach material from the aluminum. This how aluminum rusts. The three roloc pads will help fix a lot of this damage.
Using the die grinder, the pitting was cleaned up. The coarse pad is pretty heavy, and the aluminum here was pretty weak, so we had to be careful. You could TIG weld some more aluminum here, but it really was not worth the effort. If you need a perfect part, start with a better piece, for this build, it worked.
Once we worked the part over with the medium and fine pads, this is what it looked like. The anodizing was gone, the deep scratches and pits were gone, all that was left was the haze from the fine pad.
Buffing and polishing requires buffing compounds. This looks like a lot of different compounds, but there are duplicates. There are five major compounds, starting with the heaviest- emery, stainless steel, Tripoli, jeweler’s rouge, white rouge and plastic compound. There are other more specialized compounds, but these are what you will likely use.
You don’t have to have an expensive dedicated buffing motor, this bench grinder has been altered (using spacers) to work as a buffer. This will certainly work in a pinch, but you will be limited on the size of part you can work due to the close proximity of the wheel to the motor and stand.
This specialized buffing motor we picked up from the Eastwood Company is a work horse. It may not sound big, but 3\4 horsepower is a lot when you are talking about an electric buffing motor, this sucker spins to 3450 RPM, it will easily put a part through the wall, so be careful.
The first step is loading the compound. Holding the compound below the centerline of the wheel and the motor at speed, gently push it into the wheel, until the wheel colors up. You don’t want too much on the wheel, but enough to do the job. You will find the right amount with a little practice. When the wheel is new, you will get hit with all kinds of stuff, so gloves and a face shield are really important.
The most important thing when working a part is to understand the speed of the wheel and the shape of the part. The wheel can yank the (and your hand) and put it in the wall with just the slightest edge. For this part, we moved along the ribs, not against them. This was a sisal buff, used to work out the scratches.
About ten minutes of working the part on the sisal buff got the major haze gone. There is a little shine, but it is still quite dull.
We changed to a pair of spiral sewn buffs. The wheels are only 3\4” wide, so we doubled them to get more contact area. Tripoli compound was used here.
We started the process with moving with the ribs. Counting out 5 or 6 back and forth motions on each rib to ensure each rib got the same amount of attention. And it breaks up the monotony a little.
For the rolled outer edges, we worked the part across the wheel, horizontally. This helps break up the haze. You can do this on the ribs, but the part can catch really easily, so extreme care should be exercised.
The aluminum is really starting to shine now, but we have one more step.
The final buffing, sometimes called the coloring stage, uses a loose section cotton buff and white rouge compound. Make sure you work the part about 3 inches from the top edge, then flip it over and work the remainder, you do not want to catch that top edge, or it will get ripped out of your hands.
The final polish has a mirror finish. You can protect this shine with Zoop Seal or you can keep it clean and touch up the finish every couple of months with metal hand polish.
We masked off the ribs and the outer edges, then shot some semi-flat black paint on the aluminum. We also fogged the console body.
Once everything was dry, it was reassembled. All we need now are some sunglasses for the glare.
Before Polish Work
After Polish Work
wonderful write up and photos – from the professionals. from stripping anodizing to the metal polishing set up. Great contribution from you part. We appreciate. We will be sharing on our social network.