Polishing & Grindingin Singapore

The most reliable method is to specify the Ra value on your drawing — e.g. “Ra ≤ 0.8 μm all over” or “Ra 1.6 μm on machined surfaces”. If you don’t know the Ra value, specify the application standard: “food-grade per EHEDG”, “cleanroom Class 10,000”, or “architectural #4 brushed finish”. If you have a reference sample with the finish you want, send it with your parts and we’ll match it. We can also recommend the right grade if you describe your application.

Yes. Polishing welded assemblies is one of our most common jobs — grinding weld beads flush, blending into parent material, and refinishing to the specified Ra with matched grain direction. This is more complex than polishing flat sheet because the weld zone has different hardness and grain structure, and access for grinding tools is often restricted by adjacent geometry. We assess access and method during quoting.

Abrasive tools used on carbon steel become embedded with iron particles. When these contaminated tools are then used on stainless steel, the embedded iron particles deposit onto the stainless surface and corrode — causing visible rust spots within days. This is called ferritic contamination and it invalidates food-grade and marine certifications. We maintain entirely separate abrasive inventories for ferrous and non-ferrous metals and never mix them.

Polishing is a mechanical process that removes material and produces a specific surface texture (Ra value). Passivation is a chemical process — typically citric acid or nitric acid per ASTM A967 — that removes free iron from the surface of stainless steel and restores the chromium-oxide passive layer that gives stainless its corrosion resistance. Passivation does not change surface texture. For food-grade and marine stainless applications, polishing to Ra ≤ 0.8 and passivation are both typically required — they are complementary, not alternatives.

Yes. For architectural and enclosure projects requiring consistent finish across multiple panels, we use the same abrasive grade and direction throughout the batch. Panels are processed in sequence rather than individually to ensure the grain direction and scratch pattern match exactly. For very large runs, we retain a reference panel approved by the customer to check consistency throughout production.

Electropolishing is not performed in our facility, but we work with qualified electropolishing subcontractors in Singapore and can include it in the overall scope for jobs requiring Ra ≤ 0.4 μm on complex geometries, or where FDA 21 CFR or USP Class VI surface requirements apply. We manage the coordination and include it in our quote — you deal with one supplier.