Every bartender has had the issue. A tap handle ferrule unscrewing from the tap handle and remaining on the faucet. On some of our competitor’s low quality tap this happens all the time. Sometimes this can be because it was installed incorrectly by over-tightening against the faucet locknut.
Not all tap handles have ferrules. The ferrule is a conical metal piece extending from the bottom of the tap handle base. This procedure is for tap handles that have a male thread extending from the bottom of the tap handle when the ferrule is not installed.
Here’s how to reattach the ferrule in a firm way to avoid loosening again. For tools you’ll just need two 9/16” wrenches/adjustable wrenches (or one and a socket wrench). You’ll also need a ⅜”-16 bolt at least 1” long and a ⅜”-16 hex nut which can be found in the hardware section at any hardware or home improvement store.
Take ⅜”-16 bolt and hex nut (not a lock nut) and partially install the nut on the bolt as shown.
Thread the bolt into the ferrule by hand. Then thread the ferrule onto the tap handle thread by hand.
Tighten clockwise with a wrench using head on the bolt. On our tap handles you can use a good amount of force. On poorer quality tap handles if you use too much force it may pull out the stud.
While holding the bolt head in the tightening direction, take another wrench and turn counterclockwise. It helps to have the tap handle on a surface for this step.
Unthread the bolt from the tap handle turning it counter clockwise.
Once the bolt is removed you’re ready to reinstall the tap handle on the faucet. A damaged ferrule can be removed from a tap handle by following these steps in the reverse order and reverse the direction to turn.