Aluminum Polishing Part III - Pitting
Posted by Jay Schneider. Filed under Aviation.
March 3, 2011
Removing corrosion/pitting from the aluminum surface can be quite time consuming and frustrating. Typical pitting can be caused by several factors. The most common causes can be attributed but not limited to misuse and abuse, poor care and favorable atmospheric conditions . I have had excellent results removing pitting with nonwovens such as Norton’s BearTex or 3M Scotch Brite. Consequently, we offer a patented product called ScuffBall – a spherically shaped scuffing ball made from Norton’s BearTex material – available in all three grades. The user simply attaches the unit to a drill and away you scuff! Minor pitting can be removed by polishing them out as well by using an aggressive wool pad and your chosen aluminum polish. Scuff pads typically come in 6X9 inch pads. I have successfully used a 5/8” X 11 threaded 5” hook style backing plate, stuck the nonwoven pad to the plate and trimmed around it creating a very effective scouring pad. Since these nonwovens are available in three different grades; heavy cutting, medium cut and light cutting, this set up works very well when you add your favorite aluminum polish to it. Simply spread a small amount of aluminum polish to the surface, and start polishing the surface like you would with a wool type pad. I recommend a max RPM of 1000rpm’s when using this set up.
A word of caution: When working an aluminum surfaces, it is imperative that the working surface temperatures remain fairly cool. Over temping the surface may lead to oil-canning. Oil canning is a condition whereby the aluminum panel has been heated from an outside source to the point where it has expanded and will not return to its original state. A potential hazardous situation when airframes are concerned.
Work the entire surface until all pitting is cleaned up to your satisfaction. Next time we will discuss the different wool grades used in the makeup of buffing pads used for aluminum polishing.
Keep the Blue Skies Up and Happy Motoring!
Products mentioned in this article:
- 80-3250 - 2.5" Green Industrial - Medium Scuff Ball
- 80-3400 - 4" Green Industrial - Medium Scuff Ball
- 80-4250 - 2.5" Tan Heavy Duty - Extra Coarse Scuff Ball
- 80-4400 - 4" Tan - Extra Coarse Heavy Duty Scuff Ball
- 80-8250 - 2.5" Maroon General Purpose - Very Fine Scuff Ball
- 80-8400 - 4" Maroon General Purpose - Very Fine Scuff Ball