Deburring by Magnetic Spinner
Is there a machine that can deburr intricate knurls, slots and holes in small aluminum and stainless parts?
Q. We are manufacturing small, machined precision parts from aluminum and stainless. The parts have knurled areas, slots and small drilled holes that are time-consuming to hand-deburr. Is there a machine that can deburr these intricate areas? —K.J.
A. Our first recommendation for deburring small, non-ferrous parts with intricate burrs is the magnetic spinner. This is a newer technology with excellent high-energy process capabilities for non-magnetic parts. The spinner process removes hard-to-reach external burrs and interior burrs from shallow cavities.
The magnetic spinner achieves its energy from a high-speed (reversible) rotating magnetic plate positioned under the tub containing parts and media. The high- speed rotation combined with the changing polarity of the magnets creates a spinning and hopping action of the magnetic stainless steel pin media. The smaller (0.2 × 5 mm to 1.5 × 5 mm) 304 stainless media pins spin and hop by the slower rotating parts, deburring the smaller intricate areas in as little as 10 to 20 minutes.
The spinner is an excellent choice for burr removal of slots, small-drilled holes, threads, crossholes, knurled areas, small gears and internal cavities. It works well on aluminum, brass, copper, stainless, and titanium parts.
Surface finish types for commercially supplied stainless steel sheet are detailed in various standards. ASTM A480-12 and EN10088-2 are two; BS 1449-2 (1983) is still available, although no longer active. These standards are very similar in that they define eight grades of surface finish for stainless steel. Grade 7 is “buff polished,” while the highest polish—the so-called mirror polish—is designated Grade 8
This paper is a peer-reviewed and edited version of a presentation delivered at NASF SUR/FIN 2012 in Las Vegas, Nev., on June 12, 2012.
Choice of equipment, media and compounds has a major impact on your finishing applications.