by Gary E. Gadd

I first realized that aluminum could be polished to a chrome-like shine when I was washing my 1962 Honda CB77 way back in 1964. What had started as a paint discoloration caused by my leather boot sole near the shift lever had become a bare aluminum stripe in which I could almost see myself. At that point, I began to research methods of polishing aluminum.

Aluminum can be polished quickly with jeweler?s rouge and a buffing wheel but that method is a bit noisy and messy. Unless there is quite a bit to do (such as a CB750 valve cover), I take the time to hand polish small parts. This method gives me something to do indoors during the winter months (plus, I can join the kids for a movie in the den and still make some progress).

Just as proper preparation can make or break a paint job, it is necessary to have a clean, smooth surface to polish. The last part I refinished was a points cover from a CL-77. It had been banged around in a box of parts for years before I acquired it. Additionally, there were several deep scratches along the spark plug recess, left by a wrench and plug long ago, no doubt.

Removing these distractions is done with aluminum oxide ?sandpaper? (the black stuff, not the brown garnet paper). Sandpaper is classified on the basis of the surface roughness, the lower the number, the rougher the texture. The basic idea is to remove the nicks and scratches by sanding them out with a course grade of sandpaper and to reduce the sandpaper scratches by using successively finer grades.

Start with coarse 320 grit and begin. Remember that removing the scratch will change the contour of the part so you need to work on the adjacent contour to restore the original shape. When all traces of the nicks are gone, reduce the size of the smaller scratches left by the sandpaper. This should be done with a finer 400 grit. When the new scratches have uniformly covered the previous, select a still finer grit, say 600, and continue. You can keep it up all the way to 1200 or 1500 grit if you like.

However, I stop after 600 or 800 and work the surface with a Scotch Brite (or whomever?s brite) pad. This material is burned nylon and is slightly abrasive. It is used to smooth fine scratches and burrs from aluminum aircraft parts (referred to as ?Bright Boys? in that industry). Rub hard and the shine will begin to return quickly. This step will also reveal any small scratches which should be reworked with sandpaper. When all the improvement stops, complete the surface preparation with a 000000 grade steel wool. This treatment will leave a shine that is bright and shiny and ready to polish.

I use either Simichrome or Blue Magic polish. These are fine pastes which are applied with a cotton cloth (I use old, raggedy towels cut into small pieces). Another decent aluminum polish is Mother?s. Mother?s seems to be a bit more coarse than the paste types so I use it to clean up parts which have become dingy over time. At any rate, if you have cleaned up the scratches and nicks and have a smooth surface to polish on, a mirror-like shine will soon appear. Just stop when it looks right. The shine will be comparable to one achieved with power equipment, it just takes a bit longer.

Before you reinstall the part, seal it with cleaner such as Nevr-Dull. This is a tin full of cotton wadding soaked in a liquid polish. Nevr-Dull will help protect the polished surface from the elements of the road and time. I have not found a clearcoat which adheres well to polished aluminum surfaces. The surface is not rough enough for the clear coat to adhere to. It may also entrap moisture which causes those dull gray splotches to appear. Just treat your bright work with Nevr-Dull periodically and the shine will remain.

Some initial consideration should be given to ?originality?. You will change the original contour of the part when sanding out nicks. The degree will depend on the severity of the damage. Take care to preserve the original shape of the part. Some factory cleanup of the aluminum casting was not done with the greatest of care. This can be noticed as a rough perimeter or rough file marks where an assembler trimmed flash from the part. By cleaning up these rough areas, you will be modifying the part from its original configuration, even though it will look much better. Just think about what you are doing and keep your ultimate goal in mind. Do you want the project to end up as a showroom new bike, or do you want it look even better? These two competing goals will lead you down two different restoration trails.