How common is a loose bass bar?

Should not have happened again. The luthier owes you a repair unless there were other circumstances that may have caused it, like a blow to the top. My bass bar has been solid for the 42 years I've owned my bass.

 

If the bass bar was sprung, somewhat common.

There are multiple reasons why a sprung bar is no longer considered best practices.

 

Given the recent transition into the summer season and all of the crazy weather, it could easily be a soundpost rattle or other small internal issue. I have one bass that is VERY fussy with the seasonal soundpost issues.

On a related idea, 75% of the time when folks bring me a bass that they are convinced has an internal body rattle, it is actually coming from somewhere in the tuning machines....

 

I had that experience - drove me nuts figuring that one out!

 

How common is a loose bar bass?

 

Henri, where are you located? We might be able to recommend a trusted regional repair person who can help you out.

Very common; probably as common as a loose neck joint...it gets even more so when you combine a sprung joint with weak old laminated ply basses.

Tension the bass bar to "spring load" it when glued in (i.e.- carve a sharper radius in the bassbar and clamp the $#!& out of it when glueing). Later that tension pulls back away from the top. Add old loose plys and the outermost layer of ply pulls off. Now you have a loose bassbar and a delaminated top. For a solid top, especially if there is runout in the grain, a chunk of the top can pull off with it....

'As if you didn't already have enough anxiety this year.....

One of my favorite loose bassbar surprises, coupled with an additional "omega brace" add on disease attempted repair by a prior owner that caused the whole thing to explode, then there was all of the epoxy dumped into the looseness of it all to further the "add on disease":



Getting new layers in the vacuum press:




New bassbar and everything getting cleaned up:



Finally, the ends get linen overlays and a belly patch was feathered in...back on the gig!

 

Maybe I over reacted a little; that was a worst case scenario....

 

As simple as an open seam? What happens when you tap over the area?