Adjuster threads - above or below?

[CPike]

Hey folks,

I'm fitting a new bridge and am about to install adjusters. For years, most basses I have seen have the adjuster threads above the wheel, pointing toward up the strings - but lately I have seen more and more with the threads below, pointing toward the bass. Any luthiers or players out there have a strong opinion either way? Maybe I'll just do one of each, ha ha.

Thanks, Chris

[Bob Branstetter]

Originally Posted by CPike

Hey folks,

I'm fitting a new bridge and am about to install adjusters. For years, most basses I have seen have the adjuster threads above the wheel, pointing toward up the strings - but lately I have seen more and more with the threads below, pointing toward the bass. Any luthiers or players out there have a strong opinion either way? Maybe I'll just do one of each, ha ha.

Thanks, Chris

It's really one of those six of one or a half dozen of the other situations. If you were installing the Full Circle adjusters with the piezo elements in the wheel of the adjuster, there might be an acoustic reason to do it one way or the other, but with ordinary adjusters I don't see any significant acoustic or structural advantage of one way over the other. I usually install them with the threads ups, but only because I like the way they look.

[arnoldschnitzer]

Strong opinion here--threads down.

[Eli_Upright12]

I have a theory about why down might be better, but it is just that a theory , so no hard evidence backing this one. So imagine that one day many years down the road your adjusters get really tight from years of wear or whatever and you really have to crank them, are you wanting to crank them up having to kind of pull on them or are gonna want to just turn them with the help of gravity.

Also to me it just seems intuitive to have the down so that right makes it lower and left raises it. just my thoughts on it, but it should be noted that Ive never used ones facing up.

[Mark Carlsen]

IMHO a threads up bridge tends to warp sooner than threads down into the feet.It all depends on how well the threaded side is tapped and how tight or loose the post end of the adjuster is made.I think most of us out East do it threads down...

[BEEF]

With the threads facing down, wouldn't it be an easier repair if the threads were stripped?

[Mark Carlsen]

Originally Posted by BEEF

With the threads facing down, wouldn't it be an easier repair if the threads were stripped?

You would think so.. plugging and retapping a stripped thread doesn't really work that well in my experience.You can make a new foot for the bridge, but lining up the holes can be tricky.
The fact is as you raise the bridge the exposed part of the adjuster is the threaded section.The more of this threaded part showing ,the more it will rock and hence a chance for the bridge top to move or warp if the the threads are up.

[Eric Hochberg]

Originally Posted by Mark Carlsen

IMHO a threads up bridge tends to warp sooner than threads down into the feet.It all depends on how well the threaded side is tapped and how tight or loose the post end of the adjuster is made.I think most of us out East do it threads down...

Bill Merchant (NY) installed threads up adjusters on my bass in 1980 and the bridge is still straight as a straight arrow.

[Bob Branstetter]

Originally Posted by Mark Carlsen

You would think so.. plugging and retapping a stripped thread doesn't really work that well in my experience.You can make a new foot for the bridge, but lining up the holes can be tricky.

One of the other luthiers here once suggested that stripped threads in bridges can be restored by building up the (stripped) thread area with several thick coats of super glue and then re-tapping the coated hole. I've tried this on several occasions and I've yet to have one come back with the new threads stripped again. It's sure a lot easier than plugging or making at new foot and the angle of the threaded hole is unchanged. Even in a worst case scenario, this method can keep you playing until you have time to have a new bridge fitted.

[CPike]

Thanks to all for the valuable input. I, too, have a threads-up bridge with zero warp, and this bridge is going on 30 yrs old! At one point I thought perhaps the threads-down approach would lessen the twisting of the feet that occur when adjusting the height, since there is so much flat surface contact between the bridge foot and the adjuster wheel. When I raise and lower this bridge I need to keep one hand firmly clamped on the foot to eliminate the twist - even with said surface lubricated with graphite. Has this occurred to anyone else?

Chris

[Mark Carlsen]

Originally Posted by ehochberg

Bill Merchant (NY) installed threads up adjusters on my bass in 1980 and the bridge is still straight as a straight arrow.

Glad to see a bassist who checks his bridge on a regular basis and is willing to travel to NY to have one made..

[Matthew Tucker]

When I raise and lower this bridge I need to keep one hand firmly clamped on the foot to eliminate the twist - even with said surface lubricated with graphite. Has this occurred to anyone else?

Yes it happens to me with my Upton adjusters (installed threads up). Some people put a swipe of rosin under the bass foot to stop it sliding.

[Eric Hochberg]

Originally Posted by Mark Carlsen

Glad to see a bassist who checks his bridge on a regular basis and is willing to travel to NY to have one made..

Well, I was living in NY at the time. Don't think I would have gone there solely for adjusters, at least not from hometown Chicago!

[BEEF]

My Upton Bridge is threads down.
(Just purchased this year)

I wonder if they flip a coin to decide which way to go.

[Matthew Tucker]

Originally Posted by BEEF

My Upton Bridge is threads down.
(Just purchased this year)

I wonder if they flip a coin to decide which way to go.

probably not. I installed my own.