At this point you have the pistons removed from the brake cylinder, however you probably need to remove any surface rust so that the pistons can move freely.
This is called honing and the tool is called a ‘hone’.
If your brake cylinders were seized like mine, then the brake cylinder inside will more than likely look a proper mess at this point as you can see below.
To get the brake cylinder back to form, it’s time to polish the inside of the cylinder with a special tool connected to a drill.
This tool allows you to fairly quickly make the surface shiny again (you don’t want rust or scratches, the pistons need to move easily).
After a few rounds with this tool I got the surface on the inside to look drastically better, but it’s not finished yet, see the note below.
Note: I’m not finished sanding the inside of the brake cylinder, I will update this post when I complete the task, I needed to replace the sanding tool shown above as it was worn out.
See the Brakes page at MBZPonton here.