INJ WAS SPOTTING BOLTS IN #4 UNIT TRAVELROAD WHEN HE TURNED TO LOOK BACK AT A RIDE COMING UP BEHIND HIM & HE GOT HIS FINGER CAUGHT BETWEEN THE BOOM & THE CANOPY CUTTIN GHIS MIDDLE FINGER ON HI S LEFT HAND 3/4 OF THE WAY OFF AT THE 1ST JOINT HE WAS TAKEN TO HOSP & HAD IT STITCHED BACK ON