This is an incredibly simple but effective tool to combat the tremolo spring ringing. Also an easy intro into cad if you're just starting out.

I printed these as an alternative to other spring-dampening techniques I tried - electrical tape around the spring, foam in the cavity, after-market springs with a dampening coating, etc. This works just fine.

I printed these in TPU. I suggest printing in two parts as shown in the pictures. If you try to get one long sleeve over the spring, it can be a bit tricky because the “catches” at the end of the spring require some negotiation. The shorter sleeve makes it pretty easy to work around the “catches” and still maintain a snug fit on the spring.