"Penny Locked" Door Prank

Introduction: "Penny Locked" Door Prank

About: I reckon I was a maker before I knew we were called such. Growing up, my dad and I spent countless hours welding, cutting, banging, sawing, hammering, and "adjusting" things out in his shop. Other than my aw…

Ahh, nothing wreaks of good old juvenile tomfoolery than simple, cheap pranks on those with whom you live with.  Remember that picture where some wise-guy drew on your face with Sharpie while you were passed out?  This Instructable gets you one step closer to redemption and all it will cost you is about 7 cents +/- (which you may get back).

Let me start by setting the scene:  your jerk roommate is in his/her room asleep or otherwise not paying attention; their door is closed.  You are about to exact revenge with ninja stealth.

Step 1: Lock Without a Key

The point of this prank is to lock someone in a room, usually causing significant confusion as to what is wrong with the door and/or handle.

Start by pushing in the door near the top.  Slide several pennies into the crack between the door and the jamb molding about 18" above the handle.  Repeat process below the handle.  Keep adding pennies equally to the top and bottom until you can't squeeze another one in.

Step 2: Final Touches

In my experience with this prank, it is better to have an equal number of pennies above and below the handle.  When you can't add any more pennies, push the top stack down and the bottom stack up toward the handle as far as you can.  What you are going for is a boat-load of friction between the door latch assembly and the striker plate.

When done properly, the doorknob will not budge.


NOTE:  If the door is crap or the frame is loose-fitting, you may be S.O.L.  This prank tends to fail in these cases and the prank-ee just opens the door and pennies rain down.  It works awesome on heavy, dorm-style doors.

OTHER NOTE:  Obviously don't walk off and leave the person stranded.  For one, you don't get to hear the frustration or panic in their voice as they try to get out.  Also, you don't want them to be stuck in there in case of emergency.  Don't be "that guy" on the 10 o'clock news should all hell break loose.

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    10 years ago on Introduction

    LOL we used to do this to each other all the time when I was in college living in the dorm! Great fun!


    11 years ago on Introduction

    It's more fun to loosen the handles - you pull your side off, remove the bar and they're locked-in.



    Reply 11 years ago on Introduction

    That only works if the screws are on the outside.