Monday, July 30, 2012

Update on Polishing Aluminum

Dear Fellow Inventors,
Lately my friend Elliot and I are have been working on a solar oven based on a compound parabolic collector.  This has been taking longer than we expected, but has been a great learning experience.

In particular, we have found getting highly specular aluminum to be a problem.  (We actually also tried cutting a glass mirror, thought that was even worse!)  At present we have been polishing sheet aluminum to a mirror like shine.

This worked, we think, but took a long time.  Following a video on youtube called "Dirty Jobs How to Polish Aluminum" http://www.youtube.com/watch?v=gyOodLNI4BQ I went out and bought an 15 amp grinder and the necessary buffing wheels.  This was a success in that it greatly increased our polishing speed (though not quite to match the gentleman in the video, how has even more powerful equipment.)

We also attempt to polish aluminum flashing, which is cheaper than the sheet metal we had been using.  It polishes the same way, but the additional power (or perhaps heat) from our more powerful grinder tended to crinkle the surface a bit.  We found that by using a sheet aluminum backing this problem could be mitigated somewhat.

So at present we are mostly investing time in learning how to manufacture what we want, rather than the actual mathematics and design we want.  However, we both feel this is a necessary part of the process.

Wish us well--in a few more weekends we should have good reflectors to tie into our designs.