We started a series on Cleaning Media in last week’s Tech Tip of the Week on Glass Beading We continue today with a look at Airless Blasters, their uses and which media to use for which process. Next week we’ll wrap up this 3-part series with a look at Parts Tumblers.
Parts cleaning with an Airless Blaster is less labor intensive than glass beading and is generally used following thermal cleaning. In other words, once you’ve “cooked” the parts in a thermal oven, you use blast media to remove the carbonized materials left over.
Select the correct media for the job
Goodson stocks three cleaning media or shot for different applications. The first is Steel Shot, used primarily for removing materials from cast iron or steel. Used in a conservative manner, is effective in removing baked carbon and rust. But remember, leaving parts in a blaster too long will compromise machined surfaces, including deck and bearing mounting bores. One big drawback to steel shot is that it will rust and leave a dark red finish on parts.
Stainless steel shot is also available, in conditioned and cut wire. This material is used primarily for aluminum parts. The stainless shot won’t rust like steel shot so it doesn’t leave the reddish finish on cleaned parts. It removes soil and oxidation and produces a like-new aluminum appearance.
Conditioned Stainless is simply shot that has been blasted into a hardened steel plate, leaving a spherical or ball shaped abrasive. Again short blast times are recommended to minimize distortion and surface damage to machined areas. Dry parts are an absolute necessity to maximize cleaning while minimizing labor time.
Cut Wire Stainless is used to clean the worst oxidized aluminum materials. This media is very aggressive and used exclusively before a complete reman or repair including TIG welding (tungsten inert gas). All machined surfaces will require re-machining.
Just as with glass bead cleaning, these media require a complete soap and water scrub down before continuing the build. The cleaning abrasives can be trapped in oil galleys, water jackets, and bolt holes. Be very careful!
Check back next week for the final part of this series as we discuss Parts Tumbling and Tumbler Media.