Christian, Thank-you for an excellent video (as usual). Great help for me changing spring and cork (yup cork now shipping from factory). Used some painters tape to prevent scratches. Job was easy!
Great tutorial. I really should have watched it before I removed what was left of the broken spring 😕. One almost needs a second person to steady everything when you have it under tension. Oh... and make sure any cats are out of the room.
Even easier to maintain is the JoyKey automatic water drainage system. No moving parts. No spring or cork. Nothing that can break. www.thejoykey.com Check out the trombones in the picture galley.
Each company have their own style. Your local repair shop should be able to help you find the proper spring. Springs like these are a good thing to have in your case, just in case.