Building a tune-o-matic bridge for acoustic mandolins?

[Sevelos]

Ok, perhaps it is a stupid idea, but why?

On most electric guitars, adjustment of bridge height and separate intonation for each string is very easy. As you know - the bridge is made of metal and has a separate saddle for each string. Action and intonation adjustments are made by turning small screws.

Why not build some sort of adjustable bridge for acoustic instruments (e.g., mandolin) that could offer such flexibility?
For example - create a small adjustable metalic bridge, same as for an electric guitar, with 4 saddles - one for each pair of mandolin strings. Then mount this metallic bridge on a flat piece of ebony and use that as a floating mandolin bridge with the new adjustment options.

[Bill McCall]

Draw it out to scale and see what you think.

At a minimum you have a bridge base, 4 saddles, threaded insert for the saddles for movement adjustment, 4 rods/screws for the saddles to move on, and carrier for that in about .375' width, to not appear too clunky. And of course I'm sure I'm forgetting something.

Of course you'd also have to do it for a very small premium over a conventional bridge. But maybe Zeta could make something like that, if it were feasible and cost effective.

btw, you can't even find one of these machined out of metal for a 4 string electric mandolin, but of course the market there is much smaller.

[Marty Jacobson]

It's definitely feasible. The problem is, if you do something like this:
https://www.stewmac.com/Hardware_and_Parts/Bridges_and_Tailpieces/Bridges_and_Tailpieces_for_Archtop_Guitar/Tune_o_matic_Bridge_For_Archtop_Guitar.html
it'll weigh 30-40 grams at least, or something like double the weight of a normal acoustic mandolin bridge.

Basically, it amounts to putting a mute on the mandolin (reducing volume, sustain, and bass response).

The best approach might be a tune-o-matic bridge you use to dial in settings for odd setups, then copy that geometry to a solid bridge.

You could also make a grooved bridge cap with movable saddle caps, made of bone or delrin or something, to get similar functionality but without the mass of a full tune-o-matic setup.

[Richard500]

Marty, I’ve seen a bridge on line that consists of a wood base with four parallel slots and moveable hard inserts. That would certainly work, at the expense of detensioning strings a couple of times to move the inserts.

[Sevelos]

Marty - wow, I was not aware these existed.
Regarding the weight - perhaps it could be made out of Titanium, or some other light and strong material?

[thistle3585]

I build them from brass and wood and getting ready to build a batch for some tenor guitars that I'm currently building. Four or five string can fit on a bridge base or on a set of studs. However, it has been difficult to source the style of Nashville TOM saddle that I use. Either they're in big demand or production has slowed. I quit selling them retail because they are so expensive that people literally sent me emails just to complain about how expensive they were priced.

[Bill McCall]

Too bad the bass bridges don't have the right size.

https://www.ebay.com/i/362848168122?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=362848168122&targetid=859099460855&device=c&mktype=pla&googleloc=9032898&poi=&campaignid=6470549460&mkgroupid=89753846635&rlsatarget=pla-859099460855&abcId=1139336&merchantid=7874024&gclid=EAIaIQobChMItNvy5pqn5wIVvxitBh0gDAmWEAQYAyAB EgKu5PD_BwE

[thistle3585]

Marty, I’ve seen a bridge on line that consists of a wood base with four parallel slots and moveable hard inserts. That would certainly work, at the expense of detensioning strings a couple of times to move the inserts.

That bridge is made by slotting a solid saddle perpendicular with a fret saw and pressing in short frets.

[Marty Jacobson]

That bridge is made by slotting a solid saddle perpendicular with a fret saw and pressing in short frets.

Oh, ok. Yeah, what I meant was sliding the saddle forward and backwards in the 90 degree orientation to how this one is made.