FOP - Portable Sleepers Drilling Machine Three wheels aluminum folding support. The FOP sleeper drilling machine is equipped with a spindle with a quick release tip system. During operations the tip is protected by a telescopic, spring actuated, system which allows the chip flow. Share on LinkedIn (Opens in new window) LinkedIn Share on X (Opens in new window) X Share on Facebook (Opens in new window) Facebook Share on WhatsApp (Opens in new window) WhatsApp Related