Once you have chosen the pieces you would like to use to create your clock, begin brightening them up by polishing with your Dremel® Rotary Tool. If you are cleaning brass pieces as we are here, we recommend using brass brushes. These brushes are nonsparking and softer than steel so they will not scratch. Use brass brushes if you’re cleaning soft metals like gold, copper or brass. TIP: When using any polishing brushes, always run your tool at 15,000 RPM, no higher. Slowly make light passes across your workpiece. Here, we began by cleaning larger areas with the 536 brush and got into tigher spaces with the 537 brush. If you are cleaning silver pieces, use Bristle Brushes. These are perfect for light de-burring, cleaning or polishing of silverware, jewelry and other precious metals. For extra shine, use Bristle Brushes with polishing compound.