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John Zimm
Feb-19-2004, 11:25am
So, I purchased a new mandolin in December and it sounded great, but now I think the top has settled just enough to make the A string buzz on the first and second frets. I raised the bridge and it is better, but it looks to me like the bridge is as high as I should make it. So, my question is what to do. Sould I look into a new bridge, or maybe try making a new nut? I am curious what you experienced builders think. Thanks in advance for any advice.

-John.

Chris Baird
Feb-19-2004, 11:35am
The a string nut slot may be too low or the frets might not be level. I've read somewhere in a post by Lynn Dudenbostel that if you put a little baking soda into the nut slot then add some CA glue that it will instantly harden and you can then recut the slot. I've never tried it. You can tell if the slot is too low by pushing down on the 3rd fret and observing if there is any room between the string and the first fret. There should just be enough space to barely detect.

sunburst
Feb-19-2004, 12:09pm
The string height may have lowered due to low relative humidity causing the top to sink. If so, it will come back up in the warmer months. If you live where it is cold and you heat your house, you need to humidify your instruments in the winter to prevent this as well as to prevent damage that can be done by dry conditions.
You can use a humidifier in the case, but the best solution is to humidify your home. A relative humidity between 40% and 50% is ideal for you and your instrument.

Also, from what you've said, it sounds like your neck may be too straight or even slightly back bowed. If so, and if it is adjustable, a slight loosening of the truss rod should help.
This, by the way, can also be a symptom of dry conditions.

Flowerpot
Feb-19-2004, 12:14pm
Baking soda might work, but the tried and true method used by many people is filling the slot with bone dust and the applying CA glue. I've done this for years and the resulting slot is just a durable as the original bone.

Do check the nut height as Mandoplyr suggests (I would press the string down to the 2nd fret, with the finger on the bridge side of the fret). Also, you can take a short straight-edge and check the first three frets and see if the 3rd fret is sticking up. I use the edge of a 6 inch metal ruler and try to rock it like a see-saw; if it rocks, you've got a high fret.

John Zimm
Feb-19-2004, 12:36pm
Thanks a lot for the advice. Poardon my ignorance, but what is CA glue? I tend to think it may be a humidity problem because it has been very dry in Wisconsin this winter. I will check the string height tonight at the second and third strings and see what happens. I appreciate the help. You guys rock.

-John.

Chris Baird
Feb-19-2004, 1:11pm
Super glue.

grsnovi
Feb-19-2004, 1:38pm
CA = cynoacrylate ( = super glue as Chris says)

bratsche
Feb-19-2004, 2:17pm
Baking soda might work, but the tried and true method used by many people is filling the slot with bone dust and the applying CA glue. I've done this for years and the resulting slot is just a durable as the original bone.

Interesting. Will this method work using ebony dust in an overly grooved ebony bridge slot, or would something else be better? Should the CA glue be the liquid rather than the gel type, or does that matter? Thanks!

bratsche

John Zimm
Feb-19-2004, 2:19pm
Super glue.
Cool. Thanks for translating for me. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/smile.gif

-John.