Double Bass Eyeballing adjuster thread size

[bassmanbrent]

Adjusters in double bass bridges are tenuous enough and fail just in normal usage by themselves;

Hmmm… Maybe I’m just lucky, but I have yet to have an adjuster fail in all the time I’ve been I’ve been playing DB. I understand your point, but my experience has been that the pickup is the weak link. It’s a weakness I’m totally willing to accept though as it only comes up maybe once a decade. Come to think of it, I’ve only had one pickup fail so to me there’s no problem to worry about here. Just my two cents of course…

 

[james condino]

'Good thing adjusters never break.

 

[Eli Brockway]

Well, at least that's slightly preferable to the bridge itself just shattering in the middle of a rehearsal.

Been there, done that, scared the cellists, don't need to do it again.

 

[MuseChaser]

..

Been there, done that, scared the cellists, ....

See? There is ALWAYS an upside....

 

[bassmanbrent]

'Good thing adjusters never break.

I’m sure you’ve seen all kinds of crazy and bizarre stuff come across your bench! Again, maybe I’m just lucky but I’ve never had an adjuster fail. And I’ve only ever had one pickup pack it in. Been at this a while too

 

[Don Hergert]

... And again, I respect those of you who use either Full Circle or Yamahiko and love them. They both have a strong reputation for sounding great.

It just seems a shame to be hobbled when either the pickup or the adjuster fails.

Maybe the answer is to have an "emergency bridge", a previously setup non-adjuster bridge waiting in the wings ready to use whenever either the pickup or the adjuster fails. Maybe also have that "emergency" bridge previously setup and ready for an inexpensive wing piezo too, just something to get by with.

 

[JBarz]

Funny where this thread’s gone — I’ve been a diehard adjuster-pickup guy since the beginning of my tenure on this axe, but I strongly suspect I’ll be cutting more fixed bridges with Vic’s in them from here out… hard to argue with the price/sound/simplicity, they got a lot going for them…

 

[Martin Beer]

The adjuster pickups do seem to be a good middle ground between the more forward, stringy qualities of most bridge wing pickups and the more woody but less defined bridge foot or contact pickups.
If it wasn't for having a bridge with ebony adjusters that I don't want to mess with, I'd probably have gone that route too. But I've got the KNA pretty well dialled in on my bass.

 

[Chris Fitzgerald]

Just a note: my student got a 1/4x20 adjuster and we managed to put it on yesterday without a hiccup. His Full Circle is on the way back to Fishman. Thanks everyone!

 

[dperrott]

I have never noticed that before, and none of my reps have ever mentioned it in over 20 years of carrying their pickups. However, I wonder if that's an old difference that no longer applies? I just pulled some brand new 1/4"x20 and M6x1mm Full Circles from my stockroom, and both sizes have +diamond crosshatched knurled edges. The 5/16 ones I have in stock do have vertical (more accurately, slightly diagonal) knurlings.

I do feel like I remember some of the older models having vertical knurling, so maybe the comparison was of a 1/4x20 from the newer batch against the 6x1 and 5/16x18 from an older batch? That would make sense, as the 1/4" model is far more popular and more likely to have sold out and been re-ordered. Though, even the Full Circle on my Dad's Juzek, which I'm sure has been on his bass for over 10+ years, has diamond knurlings.

In any case - it seems that this differentiation may not be an intentional feature, so don't 100% count on it.

I was wondering the same thing about the knurlings. I got a m6 and they look the same as the 1/4 20. The plain m6 adjuster is fine but the adjuster with the pickup is not m6. Maybe the threads are bad. I have to figure it out when I have a chance, regardless they all have the same knurling

 

[Matt Power]

FWIW, the Full Circle is now MORE expensive than importing a brand new Yamahiko from Japan, to your doorstep. They also have superior adjusters. Even if you don't use their pickups, the Yamahiko bridge adjusters are beefier than your run of the mill aluminum adjusters.
I have had 2 FC die on me mid-performance. Never again.

 

[BPM Strings]

You could also go to the hardware store and buy one of each kind of nut and try them on the adjuster to determine the thread size. cheap and easy.

 

[james condino]

Yes sir; most hardware stores also have that big plate thingy with all of the bolt sizes that you can screw in & use for a quick ID.

 

[turf3]

Thread gauges and a dial caliper are really pretty cheap. I finally bought two sets of thread gauges (US and metric) some 20 years ago and I can't imagine how I did mechanical work without them.

I visually determined the adjusters on my bass were the 5/16-18 size when ordering my Full Circle - except they were M8 x 1.25. I ended up putting threaded inserts in the feet. That also gives me a metal-to-metal thread - I know lots of basses have metal threaded into wood, but it's always going to give me the willies.

There's no substitute for measuring the OD with a caliper and determining the pitch with a thread gauge.