String Buzz at Bridge

[brunello97]

I realize this question has probably been addressed multiple times here so forgive me for starting another thread on the topic.

I just put on some Newtone MLs on my Martin A (I wanted to try these after following this discussion:

http://www.mandolincafe.com/forum/sh...hlight=Newtone

So far they sound quite nice: mellow, balanced, a bit quiet. I am getting a bit of a buzz on the inner G string, the source appears to be at the bridge. I tried to narrow it down, it doesn't seem like a loose brace, rattle tailpiece cover. I can't induce the buzz on other strings.

The Newtones claim a .035 G but it is calipering in at .032. The Gs I took off (I've forgotten the brand) measured .035. The compensated Martin bridge is rosewood. No previous buzzing. Is that .003 enough to cause a rattle in the string seating? The outside G is basically fine. The action is as perfect as I could ever want with the bridge as it is.

Any suggestions for ways to address this? (I have an .032 nut file on hand.)

Thanks for any help!

Mick

[Stephen Perry]

Check whether slot for string is rounded over towards fingerboard and that slots aren't too deep. Funny buzzes arise from intermittent vibratory contact of string with slot edges.

[brunello97]

Check whether slot for string is rounded over towards fingerboard and that slots aren't too deep. Funny buzzes arise from intermittent vibratory contact of string with slot edges.

Thanks for the tip. I'll check that fretboard side edge out. (With some better glasses on.) If the slot is too deep (or too wide, which is my hunch, but I have to look closer even) is recutting the slot the way to proceed?

Mick

[brunello97]

Okay, dopey me. I went back and checked things out again and the problem is actually at the nut. The smaller diameter strings are now sitting too deep in the nut slot (which is pretty deep in its own right) causing the buzz actually at the first fret! Doh.

Can one fill and recut a nut slot? (Seems like I read something to that extent here.) The nut is black btw. Not sure what Martin was using in the early '50s for these.

Thanks for any further assistance,

Mick

[Big Joe]

It may be that the lighter strings are causing a bit of back bow on the neck. Doing anything to the nut will not really take care of that issue. However, you can fill the nut slots a bit by taking some bone and superglue and mixing them then putting this mix into the nut slots very carefully. A plastic toothpick can work well. Just be careful because you won't like it if you get the glue mix on the fingerboard or headstock. It can really mess up a finish pretty fast. If you don't feel comfortable doing that, your luthier can do it pretty fast. The best thing is to replace the nut, but that too is not as easy as it sounds. Filling the slots is only a temporary fix. Sooner or later a new nut will be needed... if that is the problem.

[Bernie Daniel]

...Can one fill and recut a nut slot? (Seems like I read something to that extent here.) The nut is black btw. Not sure what Martin was using in the early '50s for these. Thanks for any further assistance, Mick

Some mandolins have ebony nuts...if that is what you have some ebony dust mixed in superglue to make a paste will work to fill in the slot. If it is bone do the same thing with bone dust....

[brunello97]

Thanks, Bernie and Joe. The dust and superglue mix seems like a temporary fix that might at least help isolate the problem. Joe, I didn't even consider the 'backbow' issue, that is an interesting observation.

Joe, if I am following you on the back bow concept, the previous 'heavier' set of strings pulled the neck-forward-into different (better) alignment that created the proper geometry between nut, frets and bridge? The lighter strings allow the neck to 'bend/spring back' which confounds that ideal geometry. I guess one way to test that would be to put some heavier strings back on and see. What do y'all recommend for these old Martins, J62s? (I was intrigued by these Newtone strings and wanted to give them a try. The Martin was in line for replacement strings. Should have tried these on a bowlback..)

The nut slot does seem too deep in any event, going by those great diagrams Paul H posted up here a couple times. So as you guys are implying getting the nut replaced and the whole thing checked out by someone more competent than me is the medium range plan.

Any thoughts on ebony v bone as a nut material?

Thanks!

Mick

[Imaslipper]

You can do what I did and cut a small piece of paper, I used printing paper, and put it under the string that's buzzing at the bridge. It's not the best looking thing but by golly it works.

[bmac]

It is often possible to solve this by raising the nut just a hair using very thin veneer under it and doing any further adjustments on the nut as necessary.

[Big Joe]

I like bone much better than ebony. Ebony will wear faster and can cause other issues. Wood swells more than bone with humidity changes and will be affected by the strings working through the wood like a file. In addition, the ebony is not as dense as a good bone nut and will absorb some of the volume and midrange to high end notes. Bone is a more efficient transmitter than wood and will wear longer.

[Jim Rowland]

Somewhere on the Cafe,Paul H. has illustrated a method of squaring the offending slot and enlarging it a bit to accept a fitted piece of bone. If I remember correctly,he considered that method to provide a permanent,or at least long lasting fix. I have done it and am satisfied with the result.
Jim

[brunello97]

Thanks again, Joe, and Jim. I love the look of a nice aged nut made of bone. Replacing the ebony one with bone wouldn't be a compromise authenticity-wise. This mandolin isn't going anywhere for a long while. It is a '51, the year my parents were married. I came along quite a bit later, but that date is special to me. Jim, I recall those diagrams of Paul's and I think I can pull that off if I really prep things up well.

Probably will drop it off up at Elderly next time I'm up that way for a proper nut fix, but I can try out the temporary patch and some other strings and see where that leads me.

Joe, I'd love to stop by and visit on our yearly summer drive back down to TX. I meant to last summer (and to drop off my Gibson for the fretboard work I eventually had done up in Lansing) but our schedule got out of whack. I want to take it slower and try the Natchez Trace drive over to MS this time round. I've got an EM150 I could leave with you for awhile while we are down in Austin. All is fine with it but the pots are noisy and the whole electronics could use a look-see. I've had it forever--the neck joint has been broken twice (don't ask) and repaired and it plays better than ever. It is a work-horse!

I'll get after things with the Martin and follow up here. Thanks for the help!

Mick

[brunello97]

Okay, got the problem straightened out. Thanks, Joe, Jim and Bernie for the infill technique advice. Seems to have worked at least as a temporary fix. We'll see in a few months maybe when the next string change comes.

I appreciate the help!

Mick