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rick7157
Feb-14-2011, 9:06am
I am new to mandolins.
If I resring my Mando, where does the bridge locate for intination?

Rick Cadger
Feb-14-2011, 9:40am
Probably easiest done with an electronic tuner. Basically, when the bridge is in the right spot, the note fretted at the 12th fret should be the same as the open string but an octave higher. Also, the 12th fret fretted note and the 12th fret harmonic should give the same reading.

If the 12th fret notes are sharp compared to the open string then move the bridge toward the tail piece a little. If the fretted note is flat, then move the bridge toward the headstock a little.

If you get it so that the G strings and the E strings both give an accurate reading for open and fretted notes, then the D and A courses should be right too - as long as the compensation on the bridge is correct.

Edit to add: there's no exact spot that someone can describe. You really need to check it as explained above. However, if your mando has f-holes then positioning the bridge at the middle points of the f-holes is a good place to start. That should be roughly ball park, but you'll need to fine tune a few mm one way or the other.

Andy Miller
Feb-14-2011, 10:22am
I'll add this - it's important to be able to do what Rick has described below, so that you can correct the bridge location any time it needs it. But since your original post mentioned "restringing," I'll say this: when you restring, change them one pair at a time so that the remaining three pairs hold the bridge in place. There's no need for the bridge to move at all during restringing, so long as it's in the right spot to begin with.

Markus
Feb-14-2011, 11:06am
Agree with alltunator.

I restring one string or a pair at a time. Keeps the bridge set so I don't have to worry about it moving or tilting.

What Rick suggests is vital information to know and practice, just not needed every string change.

With hours spent every day playing I change strings monthly or more often ... but I find it unnecessary to adjust the intonation so often and saves a lot of time each string change not to. I'd prefer to check/set intonation only when it's off [or a couple times a year at most.]

I also feel that repeat tuning up/down [loose to move bridge, tight to check intonation] tends to take a bit of life out of the strings. I might be alone in this belief, but always change strings much sooner [sound dead] after I've had to adjust intonation.

I also find that when I remove all pressure from the bridge, for the next day or so the mandolin doesn't seem to be as loud or project as well until it settles in. If you play out, that's a consideration.

Jim DeSalvio
Feb-15-2011, 9:19am
All good advice above! If you start with just one E and one G string (the outermost of each) you can dial in the intonation, then install the rest of the strings. That should get it close. Intonation will most likely never be perfect on every string, so you find the best compromise across all the strings.

TheMandoKit
Feb-15-2011, 9:52am
But here's one thing no one mentioned--before you take the strings off, put a small piece of low-tack tape (like the Scotch blue masking tape or a Post-It) alongside each end of the bridge, and mark the front and back edge of the bridge on the tape. Then take off the strings, give your fingerboard a good cleaning, and put the new strings on with the bridge lined up with the marks on the tape. Final intonation adjustment may still be needed, but you'll be real close.

Also, when you remove the bridge, be sure to mark which is the treble end, or you'll have other problems.

I got this tip from Joe Vinikow of archtop.com years ago, and have used it on instruments with moveable bridges ever since.

Good luck.

Markus
Feb-15-2011, 10:19am
But here's one thing no one mentioned--before you take the strings off, put a small piece of low-tack tape (like the Scotch blue masking tape or a Post-It) alongside each end of the bridge, and mark the front and back edge of the bridge on the tape.

Great addition. I often will tack the tape on my cotton shirt a couple times before putting it on the mandolin ... a little less sticky with the addition of shirt lint - as it just needs to not fall off, not really stick on tight.

TheMandoKit
Feb-15-2011, 2:02pm
Great addition. I often will tack the tape on my cotton shirt a couple times before putting it on the mandolin ... a little less sticky with the addition of shirt lint - as it just needs to not fall off, not really stick on tight.

Not a bad idea, although the tape will only be on there for a few minutes, and I never really press it down all that firmly.

I should also mention that I have only used this on nitro finished instruments in good condition. I have no idea what it might do to a varnish finish, or a heavily crazed finish.

Markus
Feb-15-2011, 2:23pm
Ditto ... Only tried on nitro

Jim DeSalvio
Feb-15-2011, 4:28pm
Great point on the tape. I forgot that. What I use, however, is the think double-sided tape you would use to stick something on the wall. Not only does it mark the location of the bridge, but the tape squares (I cut 4 squares and "box in" where the bridge is located) will help keep the bridge in place while you get the first 2 strings installed. Works a treat!!!

TheMandoKit
Feb-15-2011, 5:30pm
Great point on the tape. I forgot that. What I use, however, is the think double-sided tape you would use to stick something on the wall. Not only does it mark the location of the bridge, but the tape squares (I cut 4 squares and "box in" where the bridge is located) will help keep the bridge in place while you get the first 2 strings installed. Works a treat!!!

Think I'd be careful with that stuff--at least the mounting tape I have seen has pretty strong adhesive. Still, if it works for you . . ..

Jim DeSalvio
Feb-15-2011, 5:40pm
Point taken on the adhesive. To be honest, I don't worry too much about the finish, and I do not press the tape on with much force. It is only on for a short period of time, but that does not mean the finish could not react or be damaged. It has not harmed my Eastmans so far.

theCOOP
Feb-17-2011, 4:57pm
what I read when it came time, and what I do:

(twelth fret should be at midway point of scale. so measure from nut to 12th fret, and double that to find out where the bridge should be). I've tried it both ways, measuring and using F holes as a guide and find measuring gives a better starting point. Besides...what if it's an oval hole mandolin?

I've also tried the tape meathod as well, but this assumes the mandolin was intonated properly in the first place.

install G string(s), set bridge under string roughly between the middle of the F holes making sure the string(s) is/are just tight enough to hold the bridge in place
do the same for the E strings
now, I like to install all the strings
set the bridge to the measure distance such that the 12th fret is half way
tighten G and E strings to pitch
check for intonation by fretting the G string(s) at the 12th fret as the first respondant said and adjust for intonation.
Do the same for the E string(s), setting the bridge for intonation.
tune up the remaining strings to pitch.

It seems, after looking at many pictures of other mandolins, that the scale on the base side is usually a little longer than on the trebble side (bridge is closer to the tailpiece on the bass side).

I've read that some people like to set intonation with the G and A strings (rather than G and E) and letting the others fall where they may.

Short of adjusting the compensated bridge saddle by removing wood to change scale length, it will most likely be a compromise with some of the strings when others are intonated properly.

Stephen Perry
Feb-17-2011, 8:18pm
If I might chime in, seems quite important to "burp" the bridge upright as the new strings settle in.

If there's lots of wood available, can listen for an out of whack course. Then adjust while the bridge is on the instrument, just slacken and file. Once the intonation is where it's working nicely, remove bridge and get the topline evened up, scrape, 600 grit, & buff. Works nicely. There's a lot of wood in some bridges.

If you're having fun with bridges, can work with the arc to give a nice progression of action height (which I don't see as clearly important - adjust if it's way off) or better, so the break angle from course to course is the same. I like that. On flat bridges, the D course sometimes seems to lie in a hole. Adjusting the plane/arc of the strings in the picking zone is a nice touch.

Markus
Feb-17-2011, 11:45pm
so measure from nut to 12th fret, and double that to find out where the bridge should be).

I forget that my blonde mandolin makes the correct location somewhat obvious, as the wood is very pale there. [and colored from the rare outdoor jam/sun everywhere else]

Jim DeSalvio
Feb-18-2011, 10:52am
Steve,

Nice post, good information. Can you explain further, "burp" the bridge. Do you mean correct any forward lean?

theCOOP
Feb-18-2011, 11:52am
Steve,

Nice post, good information. Can you explain further, "burp" the bridge. Do you mean correct any forward lean?

that's what he means. Supposedly, loosening/tightening the strings has the effect of tilting the bridge forward. You don't want this. I GREATLY improved one of those I purchased used, by straightening the bridge. After more than a year of owning it. After that, a clip on tuner worked wonders too, as the other KORG I had didn't tune it properly. The other mandolins did with the KORG, but not this one Epiphone.

michaelpthompson
Feb-18-2011, 12:46pm
I forget that my blonde mandolin makes the correct location somewhat obvious, as the wood is very pale there. [and colored from the rare outdoor jam/sun everywhere else]

My vintage bowlback has a definite dark mark where the bridge has sat for eighty years or so. Intonation was pretty much spot on when I placed in there after installing new strings.

Nonprophet
Jun-11-2011, 10:13pm
My vintage bowlback has a definite dark mark where the bridge has sat for eighty years or so. Intonation was pretty much spot on when I placed in there after installing new strings.

So this brings up a good question--several used mandolins that I've looked at had marks on the top from where the bridge had obviously been sitting for some time, and yet at some point someone decided that the intonation was wrong and moved the bridge. In all of the cases I mention the mandos were from well-known independent builders and the owners were experienced mandolin players. So, how does the bridge placement get so far (i.e. 3/16"-1/4") off? Assuming the builder knows what he's doing when he sets it up, and assuming that an experienced player knows how to change strings and check the intonation, how do you wind up with bridge marks on the top?


NP

Chris Baird
Jun-11-2011, 10:31pm
Different gauge strings need different compensation, as does a different action. The builder could nail the bridge location and it would be right, until the player tried a different set of strings or changed the height of the action... then the bridge is in the wrong spot.

michaelpthompson
Jun-11-2011, 10:58pm
Plus, the top can sink, the neck angle can change. and theoretically, somebody could screw it up when changing the strings. ;)

Markus
Jun-11-2011, 11:53pm
Different gauge strings need different compensation, as does a different action. The builder could nail the bridge location and it would be right, until the player tried a different set of strings or changed the height of the action... then the bridge is in the wrong spot.

Very well put.

When I've altered my action significantly, I had to move the bridge to get proper intonation. Short-scale instruments are picky about changes, but need correspondingly small changes.

You're not going to find one of those bridges very far away from any markings - unless the bridge itself was changed at one point.

Ivan Kelsall
Jun-12-2011, 1:09am
One point - Before you do anything,tune your Mandolin up to pitch & check the bridge position as it is now.. It may be spot on,it might not be. If it is,then as suggested,put a piece of low-tack masking tape at each end of the bridge foot, & mark on it the front & back face of the bridge.This will give you your 'starting point' if the bridge should accidentally move during re-stringing. If the note at the 12th fret is NOT a true octave above the open strings,then the bridge is not in the right position. So,before you re-string it,use the old strings to set it right & then mark it's position.When the bridge is correctly positioned,change your strings & re-check the bridge position. You can do this easily with any pair / pairs of strings tuned up to E/A/D/G but at a lower tension ie.an octave below true pitch still using your tuner. The lower tension makes moving the bridge back & forth a great deal easier,also, make sure that the bridge is truly upright & not sloping forward or backward,
Ivan

P.D. Kirby
Jun-12-2011, 6:26am
I am new to mandolins.
If I resring my Mando, where does the bridge locate for intination?

Welcome to the forum Rick, since no one posted the link I will, this site has a lot of useful information the link takes you to the Mandolin restringing but take a little time to look around and if you aren't careful you might learn something. As previously posted measure from the nut to the 12th fret then from the 12th fret an equal distance to the center of the bridge, fine tune using a good tuner and you are all set. I always remove all the strings and the bridge so I can give the Mandolin a good polishing.

http://frets.com/FRETSPages/Musician/Mandolin/MandoString/mandostring1.html

Good Luck
Phillip

Bill Snyder
Jun-12-2011, 10:47am
Looking at his profile it would seem that Rick7157 has not logged in again since asking his question back in February.

rmbrasington
Mar-12-2013, 10:54pm
Thanks for the info here. I got lucky for sure but just about hit it spot on the first try. I feared this like going to the dr/dentist. Thanks again. Mark

sausgirl
Apr-22-2013, 7:19pm
"Besides...what if it's an oval hole mandolin?" BINGO! Thanks for the info,I will try it by ear and measuring.
Regards,
Jan ;)

Mike_the_limitless
Feb-01-2017, 10:23pm
SO question....New to this.. My E string is the same open and at the 12th fret, it stays E open and at 12th.

My G is in tune open, but goes to A at 12th. This is bad yes?

pops1
Feb-02-2017, 1:00pm
SO question....New to this.. My E string is the same open and at the 12th fret, it stays E open and at 12th.

My G is in tune open, but goes to A at 12th. This is bad yes?

Are you sure it goes clear to A? If it does your bridge needs to go away from the headstock only on the G string side.

Mike_the_limitless
Feb-07-2017, 7:31pm
Yes, using guitar tuna, open G at 12th goes to low A4

- - - Updated - - -

My bridge will be very far back if i go any farther, 25 degrees maybe.

Mike_the_limitless
Feb-07-2017, 7:36pm
Ok i tried another tuner, and its very nearly perfect middle G. Its a little low G though.

It was the app i was using. The bridge is set up perfectly now!

dschonbrun
Feb-12-2017, 1:44pm
There are different ways to replace strings to minimize the change in intonation. The first thing I would do is use painters tape to make the current position of the bridge, all 4 sides (assuming that the intonation is good).

If the intonation is not good, then follow directions from previous posters on 12th fret validation for G and E strings.

Hope this helps.

Best,
D