Shimano disc brake piston exposure tool

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Shimano technical training has a system in place for cleaning the pistons on disc brake calipers that relies on cutting down a bleed block to create a piston exposure tool. The process of hacking apart a bleed block with a hacksaw seems like a tedious task, so I developed this design as an alternative method that achieves the same effect without requiring the use of a hacksaw. The new design functions like a traditional bleed block but allows for the piston to extend out of the caliper far enough to clean the side of the piston before pushing it back in and repeating the process with the other piston. This innovative approach streamlines the cleaning procedure, eliminating the need for unnecessary cuts and hassle. After conducting extensive research, I couldn't find any documentation on this process outside of Shimano's industry-specific technical education materials. However, the basic concept should be easy to understand by examining the accompanying photos. The step-by-step cleaning procedure is as follows: First, push both brake pads into the caliper. Next, insert the new tool and pump the brake while observing that the piston on the side of the tool with the cutout extends. Stop once the piston hits the tool. Remove the tool and use rubbing alcohol and cotton swabs (Q-tips) to clean the sides of the piston. Apply Shimano mineral oil to lubricate the sides of the piston, then push it back into the caliper. Repeat this process for the other piston. For reference, Park Tool has a video available that explains the process without requiring any special tools.