Double Bass Nut Shim Material

[IdealWay]

I'm getting more rattle than I like on all of my open strings, which continues to worsen as the nut slots wear down and strings move closer to the fingerboard. Seems that shimming the nut is the move here, and I'm curious what the ideal material is. Would a thin piece of ebony superglued under the nut work? Any insight on process and links to material would be appreciated. Thanks in advance

 

[turf3]

I'd probably use some beer can aluminum to start with. Easy to stack it to get the correct height.

 

[IdealWay]

I'd probably use some beer can aluminum to start with. Easy to stack it to get the correct height.

Perfect, chugging a beer now to harvest the aluminum.

 

[Don Hergert]

I endorse aluminum!!!

... At least to get to the proper measurement because it has a consistent thickness. Once that measurement is acquired, your first idea of gluing on a strip or two of ebony veneer sounded spot on.

But having the action lowering by itself might be something else... Is this a seasonal thing? Are you sure your DB's top is not sinking?

(Since you're in Asheville, you might want to talk with @james condino.)

 

[IdealWay]

Thanks for the insight. Appears the strings are only lowering at the nut, which I can see with strings removed - grooves are pretty much flush with the fingerboard. Top is sturdy and proper shape. Last setup was in 2011 at Bass Violin Shop in Greensboro, so it's been a while. Love everything else about the tone/feel, except the open string buzz and hoping to remedy before it gets worse.

I read that black tagboard could work instead of ebony, and may actually be easier to work with. Although unsure of the tonal impact of one vs the other. Anyone have experience with this? Also what type of glue is best?

 

[Don Hergert]

I've read the same about tagboard...

Have you recently changed strings? Or could the strings be reaching their end of useful life?

I've never read or experienced a nut "wearing down"; I've seen them break or have the grooves adjusted too low, but have never seen them wear down. I suppose it's possible with a lot of string changes, but with as little movement as normally happens in that area -- and as hard and oily as ebony is -- it would take a lot of string changes to do that. So that's why I was wondering if something else has changed or is changing with the DB itself.

 

[turf3]

By the way it's my understanding that the walls of a standard aluminum can are thicker at the bottom so you get a little adjustment from where you cut the shim.

 

[fretno]

Let’s gets some measurements.
Check relief first and set it. I personally prefer very little relief. This with proper nut work , fret work and bridge adjustment are what we are dealing with. Relief, This changes with temperature swings and can cause this buzz. Measure from the top of the first fret to the bottom of the open string. Nut material usually doesn’t wear away all that quickly.

 

[porkynuggets]

Let’s gets some measurements.
Check relief first and set it. I personally prefer very little relief. This with proper nut work , fret work and bridge adjustment are what we are dealing with. Relief, This changes with temperature swings and can cause this buzz. Measure from the top of the first fret to the bottom of the open string. Nut material usually doesn’t wear away all that quickly.

I agree it would be weird for the nut to be wearing down. It would also be weird to find frets on a double bass, maybe not impossible though.

 

[fretno]

Doh lol hmm I have seen it. Sorry Lads

 

[fretno]

You guys don’t have adjustable truss rods in those things either huh?

 

[fretno]

So since I’m here the typical FSO is pretty adjustable and several different player types could adjust it to suit them. What does one do to experiment with action and set up on the big fiddle?

 

[sawzalot]

I have successfully put a drop of superglue in the nut slots as a shim material. Super easy, just make sure you tape off everything in case the superglue goes somewhere you don't want it to.

 

[Don Hergert]

So since I’m here the typical FSO is pretty adjustable and several different player types could adjust it to suit them. What does one do to experiment with action and set up on the big fiddle?

Sort of off topic, but "relief" (aka, scoop in DB land) is built into a fingerboard by the luthier; it is a complex process which also involves the curvature of the fingerboard (arch). Necks and fingerboards are stiff enough that a truss rod would not work. So if a person goes from thin high tension strings to fat low tension strings, a visit to a competent DB luthier is in order.

Many DBs also have adjustable bridges to adjust the action, usually measured at the end of the fingerboard. But of course that does not adjust scoop.

FWIW, some of the early forms of what would become double bass do have frets, adjustable gut strings located at fret intervals, tied around the whole neck. But still, scoop has to be built into the fingerboard.

Back on topic, if nothing else is involved, if the OP has changed to a different tension or thickness of strings since the last setup, that could explain the buzzing. One nuance that has not been described is if the strings buzz when they are stopped somewhere above the nut???

 

[unbrokenchain]

I have successfully put a drop of superglue in the nut slots as a shim material. Super easy, just make sure you tape off everything in case the superglue goes somewhere you don't want it to.

 

[logdrum]

I heard the Aluminum ( pronounced AlumiNIUM as in plutonium ) used by Guinness works best

I used the copper foil that we use for guitar control cavity shielding and I can control the thickness much better as I can build up layers of the foil. They also sell aluminum foil tape for duct work and yes it is much thicker than food pre aluminum foil

 

[fretno]

Sort of off topic, but "relief" (aka, scoop in DB land) is built into a fingerboard by the luthier; it is a complex process which also involves the curvature of the fingerboard (arch). Necks and fingerboards are stiff enough that a truss rod would not work. So if a person goes from thin high tension strings to fat low tension strings, a visit to a competent DB luthier is in order.

Many DBs also have adjustable bridges to adjust the action, usually measured at the end of the fingerboard. But of course that does not adjust scoop.

FWIW, some of the early forms of what would become double bass do have frets, adjustable gut strings located at fret intervals, tied around the whole neck. But still, scoop has to be built into the fingerboard.

Back on topic, if nothing else is involved, if the OP has changed to a different tension or thickness of strings since the last setup, that could explain the buzzing. One nuance that has not been described is if the strings buzz when they are stopped somewhere above the nut???

Thank you Don! Wow that is pretty cool. Oh there is also a movable neck joint too right? Gotta steam it or ? Appreciate it though Don. Cheers

 

[ProfChris]

Here in the UK I can buy a small piece of ebony veneer (4 x 6 inches) for £3 (less than US$4) delivered. Veneer sheets are a consistent thickness, 0.6mm/0.024 inches. I'd use that because it gives finer adjustment than a scrap of beer can, and if (say) two thicknesses do the job, I just glue them on and the job is done.

Pretty much any hardwood veneer would work too, just colour the edge black once glued on.

 

[AGCurry]

Thank you Don! Wow that is pretty cool. Oh there is also a movable neck joint too right? Gotta steam it or ? Appreciate it though Don. Cheers

In a double bass, a "movable neck joint" is a catastrophe in the making.

 

[eh_train]

... What does one do to experiment with action and set up on the big fiddle? ...

Fretno,

The answer is 'lots'. Really, sometimes, very lots. Particularly when modifying the fingerboard, the only way to work on it is to take the strings off (or loosen them a lot and get them out of the way of the board), then make your modifications, then put the strings back on, then re-tighten them to pitch, and then test the result. Repeat as needed.

There is a special vocabulary that I use after the fourth and fifth times this happens.