Angle Grinder Polishing Discs

Discs for satin finishing and mirror polish stainless using an angle grinder

unitised velcro finishing disc on back up pad

In metal fabrication having angle grinder polishing discs to hand can be the difference between success and failure. Here we detail the main differences between grinder polishing discs and suggest which discs would work best on your angle grinder. By polishing we are referring to Satin polishing and mirror polishing as 2 distinct categories.

2 points to note:

Working with a variable speed grinder is definitely best when finishing and polishing. But where you can we have recommended discs that will work on a standard 4 1/2″ grinder.
Higher torque is helpful when using angle grinder polishing discs so we would also recommend using 5″ / 125mm grinders with at least 1000 watt power unit.

Satin Polishing Discs for Stainless Steel

Satin finishing is the most common stainless polishing process. If you need to use angle grinder polishing discs then it is important that the correct preparation has been done.

A general purpose satin finish the coarse surface conditioning flap discs such as the Cibo LVT RC1 disc.
For a 240 grit satin finish we would recommend the LVT RC2 medium grade disc.

As soon as you want a finer finish then the Cibo RebelOne unitised products become an excellent choice.

The MAG grade 5 unitised disc leaves a lovely soft satin finish finish. It blends very well with a 320 grit finish, commonly seen on tubes and rails
For a super satin finish then the SAG grade 5 is the ideal choice. this will leave a soft pre-polished finish which looks bright with a very light satin structure to the finish.

If working with a variable speed grinder we recommended working in the range 3,000 to 5,ooo rpm. All the discs are rated safe to use on standard grinders running at 11,000 rpm.

Mirror Polishing Discs for Stainless Steel

There are two families of angle grinder polishing disc for mirror polishing stainless. Firstly we have the unitised and felt discs and a glass fibre backing which fit directly onto the grinder. The second option is the Cibo velcro grip disc system which you can buy in the Time Saving Kits or as individual products.

Products for repairing a damaged mirror polish or restoring a mirror polished finish after welding. Either way. For a commercial mirror polished finish the SAG unitised discs are the best option.

After welding finish the surface to a 240 or 320 grit finish ( RCD medium or very fine combination discs). Then you can use the SAG grade 5 unitised disc to pre-polish.
If you need to remove light scratches such as a steel rule dragging across a mirror polished surface then use the SAG 5 disc immediately. SAG 5 has the power to remove light scratches and leave a blended, pre-polished finish.
Once a consistent finish has been created with the SAG disc then you can mirror polish with felt and our PV/101 green polish. The best disc to use is our VAP/Z/115.

n.b. We originally developed a felt flap disc but the edge wear was far too great to be cost effective. Although the VAP felt discs are twice the price they last up to 10 x longer.

For the full process options look at the Cibo Time Saving Kit options which you can also see on our website. And for tubes, go to TSK06, Mirror polishing tubes. For mirror polishing flat sheet and box section go to TSK04

n.b. We do not recommend using the Trizact velcro grip disc systems on standard speed angle grinders. The Trizact product gets hot very quickly and will not work effectively at 11,000 rpm.

Angle Grinder Finishing Discs for Steel

Satin polishing on steel is much less common. In principle we would advise using the same products and processes as we have recommended for stainless steel. In steel applications the main use for metal polishing discs is for blending prior to painting or powder coating. If you want to use a flap disc then the best disc to use is the Medium conditioning flap disc. Alternatively, it is easier to blend to a flat surface with velcro discs such as the VTMA FE1. Use a dedicated back up pad such as the 115VEL//SCN.

Polishing Discs for Aluminium, Brass & Copper

The best angle grinder polishing disc to have in your locker for polishing aluminium, brass & copper is the SAG grade 5 disc. Use the SAG 5 for removing oxide, blending scratches and for pre-polishing the aluminium to leave a bright pre-polished finish.

Need to remove aluminium tig welds? Step up to the SAG grade 6 disc which still leave a super fine finish and remove the weld.

To see all the range of metal finishing discs follow this link. Or to see the wider range of flap discs this link will take you to the page including the ceramic and zirconia flap discs.