Take a look at the workmanship in the instrument panel below:
The instrument panel is from a 1948 Simca-Gordini Type 5 race car on display at the Lane Motor Museum here in Nashville. Notice how the aluminum backing has swirl marks in it. That swirling is called “Engine Turning” and it is not easy to do, or rather it was not easy to do in 1948. The effect is accomplished by chucking a grinding wheel in a drill press. The press is lowered onto the aluminum until the grinding wheel barely touches and scratches the finish. The material in the press is then moved slightly, the press is lowered again to form an overlapping pattern, and then repeated over and over again. It was a time-consuming artistic touch, but well worth the effort in my opinion.
There are many more photographs taken at the Lane Museum on This Page of my web site.