Double Bass Clatter from endpin when moving double bass

[Transistor]

I have a Thomann / Hora 22 3/4 Europe double bass. I'm 183 cm tall and I play with the end pin out past the third groove.

I have a minor problem that when I move the bass (crowded acoustic venue) to relocate the pin on the floor I get a disconcerting clatter from the instrument unless I lower it to the floor very gently.

• The sound is a combination of metal and wood.
• The pin will not come out of the clamp for examination. (There are a couple of what appear to be welding spots on the top end of the pin to prevent it falling out.) I don't want to remove the tailpiece to examine it - if I can avoid it.
• I can reproduce the sound by slackening the thumb screw and hitting the pin so I suspect that the pin is rocking in the pin holder and I'm getting metal on metal contact which resonates in the body giving me the woody tone.

Has anyone else experienced this and / or can anyone suggest a fix to reduce the problem?

Many thanks.

 

[SAlcott]

Try filing a groove in the shaft at your preferred spot.

 

[BPM Strings]

Is there a lot of the pin still extended into the bass when it's in playing position? If so, the sound might be that end vibrating around. You could cut off the excess.

 

[eh_train]

... You could cut off the excess.

Yes, especially if there's lots of endpin "floating freely" inside the bass - it can act like an antenna, picking up and amplifying vibrations.

Also, if you pull the pin out as far as it will go, then cut it at the base of the collar, you'll remove the "stops" at the top of the pin (just pull out the cut-off part through the f holes when you've finished sawing).

 

[Michael Case]

Is that tip screwed on? Maybe that's loose, I know my screw on tip will make noise when I stand the bass on it if the tip is loose.

 

[Transistor]

Thanks, guys. I finally got to the bottom of the problem.
I noticed that I only get the rattle when playing on tiled floors at home. My Friday night singalong has a wood floor and a recent recording session had a carpeted floor. Neither gave the "clatter" problem.

I discovered that the pin was sinking through the rubber bung on the pin end and touching the floor. It looked OK when the bass was on its side - but it was uncompressed then because the weight was off it.

I 3D printed a new bung in PLA and glued a layer of rubber on the bottom. All is well!

 

[Don Hergert]

Crutch rubber ends incorporate a steel washer which seats the sharp endpin point and prevents it from piercing through the end. That approach might work for you too.

 

[41 Hz]

d a new bung in PLA and glued a layer of rubber on the bottom.

I've also had this issue at some point. A 'chattering' when playing on tiled floors. I use the Wolf Super End-Pin and when that rubber on the bottom gets worn down, the metal 'cup' will chatter on hard surfaces in a particular orientation.