MP-Series
Magnetic Pin
The magnetic steel needle is made of a mixture of special metal materials and 304 stainless steel, offering higher wear resistance and bounce. Specifications range from 0.2mm to 2.0mm diameter and 2mm to 20mm length, with hundreds of models available. The thicker the needle, the stronger the polishing strength. For stainless steel and hard parts, use needles above 0.8mm diameter. For copper and aluminum (soft materials), use needles below 0.8mm. Generally, 5mm long steel needles are recommended for polishing.
About the Magnetic Pin
Magnetic pins are the main polishing media for all Guangu Tech machines — from the compact GG8520 to the flagship GG2980. They are made from a mix of special metals and SUS304 stainless steel. This blend gives better wear resistance and bounce than standard pins. They last longer and polish more evenly. Add polishing liquid to the bucket for optimal results.
Picking the right size is key. The rule is simple: thicker pins polish harder. For hard metals like stainless steel, carbon steel, and iron, use pins above 0.8 mm diameter. The extra weight helps remove burrs from tough surfaces. For soft metals like copper, aluminum, brass, gold, and silver, use pins below 0.8 mm to avoid damage.
Pin length matters too. Short pins (2–5 mm) work best for small, detailed parts with tight spaces and blind holes. Long pins (8–20 mm) polish larger surfaces more aggressively. The most popular size is 0.5 × 5 mm. It works well for most jobs. Learn more about pin selection in our article on how magnetic polishing machines work.
The full range goes from 0.2 mm to 2.0 mm diameter, and 2 mm to 20 mm length. Hundreds of sizes are available. Custom sizes can be made on request. Each pack weighs 1 KG (150 × 80 × 80 mm).
Precinova stocks the most popular sizes for fast delivery. We can also source any size from Guangu Tech's full catalogue. Contact us to pick the right pin for your parts and machine.
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