help! frets too high? Bridge too low? Colombian mandolin

[Dave LaBoone]

Hi guys,
I have a Colombian mandolin that I'm having problems with. Would raising the bridge help my issues???

-on the G string, both the 8th AND 9th frets sound as E
-on the D string, both the 8th AND 9th frets sound as B
-on the E string, both the 3rd AND 4th frets sound as G# (or the G sounds sometimes, but with definite buzzing from 4th fret)

Here's a video so you can hear the issues:


Thanks in advance!
-Dave

[Explorer]

It sounds like you're dealing with uneven frets, either higher frets on the upper fret or worn/shorter frets on the fret which is being overridden by the next fret.

Raising the bridge might solve some aspects of the problem, but isn't the actual fix needed.

I'm hesitant to offer solutions because I suspect you don't have a lot of set-up experience, and I don't want to contribute to you messing up an instrument. I'd suggest you go to a decent repair person and ask for a diagnosis and repair estimate.

[DavidKOS]

It needs to have the frets leveled. Many of those Latin-American folk instruments could use a tiny bit more fine set-up work to be really playable.

What the heck is that metal plate on the bridge?

Cool axe.

[NickyB]

Dave, that is a nice looking instrument. Your problem with the buzzing and fret interference can be fixed by raising the bridge but this will play havoc with the mandolins intonation. Checking the neck for warping and if straight having the frets levelled and dressed properly (check nut also) will allow you to adjust the bridge for your preferred action. The intonation then will depend on the accuracy of the fret spacing and position of the bridge with regard to your mando's scale length.

[EdHanrahan]

Checking just to find uneven frets isn't particularly difficult. Way back, I cut an old steel ruler into various lengths that can be rocked across 3 frets at a time to find out who's high or low. It's done almost more by feel, and hearing the clicks, than it is by sight. The actual leveling you might leave to a pro.

Stewart-MacDonald now makes a "fret rocker" that does the same job a bit more eloquently, and more expensively. I DO recommend looking up the Stew-Mac tool as they give some good hints as to what you're looking for. Apply that knowledge to, oh let's say, an old cut-up ruler?
(Just looked, and here's Stew-Mac's: http://www.stewmac.com/Luthier_Tools...et_Rocker.html
Sort of hate to say it, but folks on eBay are selling knock-offs for way cheaper.)

For a real understanding, Rob Meldrum's on-request set-up e-book should be most helpful (just ask via PM to Café member "Robster", I think). There's also Frets.com for how to handle all sorts of related issues.

[ProfChris]

You have a free fret rocker in your pocket - a credit card has nice flat sides and will span three frets (hold it vertically for close-spaced frets). Not as accurate as the precision version, but pretty close.

[Willie Poole]

If after checking the frets and they seem OK I would take a close look at the neck being bowed, with out a truss rod adjustment that is the most likely problem and it doesn`t appear to have a truss rod that can be adjusted...That medal plate on the bridge may be a device to keep the pickers hands off of the strings, never seen that before but might not be a bad idea...

Willie

[Dave LaBoone]

Thanks for the suggestions, guys, I've got Rob's ebook and will try some of your tips. It's a cool instrument that belonged to my wife's great-grandfather, and I'd love to get it back in playing shape.

The metal piece to rest your picking hand is, indeed, pretty cool.

Best,
Dave