Sooo, I've got this friend. He's a bit well off and a fellow flying enthusiast. He actually owns his own plane, unlike the rest of us that just rented the thing by the hour. John has a beautiful old Cessna 140 that he has restored and lavishes his love on. Sometimes he even sleeps in the hanger. yeah, he does.
So, he had to replace the wide rubber weather striping on the hanger doors that slides up in two parts. The weather strip is an almost 3 inch wide strip of rubber a bit less than 1/8 of an inch thick, with these stringy fiber reenforcement threads running through it. The hanger door is tall enough to clear the tail of the aircraft being pushed into the hanger, so we had to use a ladder to reach the top of the hanger door. A hole was drilled every foot and a half for the anchor bolt to the door frame. Job was easy and John was just going to put the ladder away when he noticed that the rubber needed to be notched to fit over the padlock hasp on the doorframe.
John says to hold. up, there's a Stanley knife in the tool box so he walks to the back of the hanger to look for it. While he's rummaging around in the tool box looking for the utility knife, I go and take the little SAK classic out of its keyring sheath, and proceed to make a neat cut into the rubber to clear the hasp, and then down and back, making a neat squared off U shape flap so it will clear the lock hasp. John comes back with a Stanley utility knife, looks at the cut out and asked what I used. I tell him my little classic did the cutting. He calls BS, that little thing couldn't have cut that heavy rubber strip. I hand him the square cut out piece and tell him to hold on other end. I then cut the piece in half. Yes, I had to do a little sawing, but the little SAK blade cut right through the rubber weather stripping. John was amazed that itty bitty little thing did it.
Moral of story; never under estimate a SAK, even a teeny one.