There are different ways to polish raw stainless steel to the mirror surface, but all these ways require three stages, including rough abrasive grinding stage, polishing stage and buffing stage. Here we have listed a way to polish raw stainless steel to the mirror surface step by step using a bench grinder.
#1—Rough abrasive grinding stage-polish raw stainless steel
Start with a grit 80# abrasive flap wheel to grind and sand the item. Change the grit 80# flap wheel to a grit 120# flap wheel until the sand hole on the surface of the item are only the size of a needle tip. Then use grit 240#, 320# and lastly use 400# flap wheels. Each finer polishing step should be cross-polished 90 degrees from the previous process, and make sure every line from the previous operation has been taken out before you continue to the next step.
#2—Polishing Stage-polish raw stainless steel
Start with a hard-treated sisal polishing wheel, attach the sisal polishing wheel to the bench grinder, and apply the black polishing compound to the sisal polishing wheel. Polishing the item with medium pressure and 90 degrees to last sanding process. The sisal fibre has natural cutting properties, and dip treatment makes the sisal wheel more aggressive. It is very important that you remove orange peel, grinding marks and scratches left from previous abrasive operations and leave a uniform finish.
#3—Buffing Stage-polish raw stainless steel
Attach the colour stitched cotton polishing buffing wheel onto the bench grinder, and apply green polishing compound to the colour mops. Polish the item with medium pressure. This step will remove the dull finish left from the last operation, and leave the workpiece with a semi-bright finish.
Change the colour stitched cotton buffing wheel to a white loose fold cotton buffing wheel, and apply the white polishing compound to the loose leaf cotton buffing wheel. Buff the item with light pressure, this will leave the workpiece with a bright finish.
Change the loose-fold cotton buffing wheel to a loose fold flannel buffing wheel, and apply the white polishing compound to the flannel buffing wheel, buff the item with light pressure. You will get a mirror finish from this step.