Sanding is an important step for a true mirror shine reflection. The better the sanding preparation the better the shine.
Choosing the grits is determined by your job. Start by looking at your surface to determine the severity of damage.
Pitting, stone chips & deep scratches:
These can be sanded out with 180, then 400, and finally 600 grit before I cut/polish. But very badly pitted bars will sometimes require 80 grit to start with, then the steps mentioned above.
Light pitting / scratches:
Can be sanded back with 400-600 grit
Deep acid streaks / blemishes:
These can be lightly sanded with 600 grit before polishing.
No pitting, stone chips or scratches:
Choosing your sanding tool:
There are 2 methods I use when sanding.
5″ Electric orbital sander: with 6″sand paper pads (preferrably with no vent holes in the paper to reduce “pig tailing” scratches from the velcro loops on your sander). The 6″ paper pads also are easier to remove and are required when using high speed backing plates.
High speed backing plates: Are a soft edge plate designed to use with a 7″ variable speed polisher. They are ideal on jobs that require lots of sanding with heavy grits.
*High Speed Backing plate available in store.