A brake piston compressor is provided. The brake piston compressor includes: two blocks; a forcing screw configured to engage the blocks to selectively bring the blocks closer together or farther apart from each other depending upon which way the forcing screw is turned; two pads each pad configured to be slidably engaged with at least one block; and a locking mechanism configured to engage and disengage to lock one of the pads to one of the blocks when the locking mechanism is engaged. A method of operating a brake piston compressor is provided. The method includes: sliding a pad into a channel in a block; locking the pad to the block; and turning a forcing screw to move the pad and block with respect to a second pad and block.