Ok, it's looking pretty. Now what?

[Phaserbait]

Hi all!
I've been gone awhile, and between waiting for the stuff I ordered to come in and work, I haven't had much time to work on my mandolin that I am refinishing. I am still putting varnish on, and that has been a trip! Tried spraying the varnish with a airbrush system, but the varnish as too thick. So I am brushing on carefully and in sections, to keep drips from happening. The tuners finally came in after being on back order, and I am rather proud of the artwork. I will post photos after I am done with varnish. My next question is: I need step by step help on where to put the bridge. I read the thread here about it, and I think I am missing quite a bit. What is the meaning of 12th fret harmonics? I do know I need to sand the feet of the bridge for a smooth fit, but I am in the dark from then on. Any help will be wonderful!
Bless you all!
JoAnne

[bmac]

measure from this side of the nut to the center of the 12th fret. double that distance and place the center of the bridge at that point. That will give you a close position for the bridge. With a wax crayon lightly mark your bridge position on the mando. Use your electric tuner to fine tune the the bridge position after it is strung up.. It should read the same note when fretted at the 12th fret as when played open,,, but an octave higher. When they read the same note on your tuner you got it.

Before you do string it up though make sure your bridge is making perfect contact with your mandolin body at that point. Frets.com has good info on sanding bridge feet. and the whole process.

[Willie]

What Bat said...That distance from the edge of the nut to the center of the bridge should be 13-7/8 ins...That will give you a good starting point to check your harmonics with the electronic tuner....

Good luck....Willie

[sunburst]

What is the meaning of 12th fret harmonics?

If you lightly place your finger on a string over the 12th fret, pick the string and immediately remove the finger from over the 12th fret, you will hear a "chime" note. That is the octave harmonic of the string, and since the node (the place you put your finger to get it to happen) is approximately over the 12the fret, it can be called the "12th fret harmonic". The chimed note will be one octave higher than the open string, and when the bridge is correctly placed, that note will be the same as the note you get when you fret the string at the 12th fret.

[Ben Milne]

Check out Frank's instructions on how to fit the bridges to the body at frets.com.

[robster]

You'll also want to make sure you cut your nut slots so they angle downward towards the tuning pegs. This assures a clean break for every string at the front of the nut. Otherwise intonation can be off.

If you're using a floating bridge your intonation adjustment is easy and you don't need to be too worried in your initial setup, as adjustments can be made by moving the bridge around. If you have a fixed-place bridge you are right to be extra-careful in the placement. Once it is in place you can make very minor adjustments by filing the top of the bridge where the strings hit it, but it's persnickety.

If you want a free copy of my e-book on setting up a mandolin, e-mail me at rob.meldrum@gmail.com. Sounds like a fun project!

Rob