Lowering the Nut on a Mandolin - Could it be done in-situ

[Greengrass]

Hi folks,
was reading Frank's great article on frets about installing/replacing a nut and setting the nut action.

The article confirmed my suspicion that the nut action on my mandolin is a bit too high.

Would it be possible to lower it without removing ?
Wondering if there are any reasons I shouldn't do this !!

I was thinking of deepening the string slots and then just filing down the height with a mill file and then sandpaper.

As you will have gathered I am NOT a Luthier :-) and haven't done aything like this before.

Thoughts ?

Thanks.
Greengrass

[Paul Breen]

Yes the action can be lowered without removing the nut.

Reasons you should not do it?

This is an adjustment that requires a little finesse. A poorly slotted nut is the most common cause for dead or muted sounding strings or strings that sound more like a sitar when plucked. If the slot is to wide or to narrow or the string does not break cleanly at the nut's leading edge or the slot is ramped to steeply toward the tuners you can create more problems for yourself. The goal for a well adjusted nut besides better action is to acquire the cleanest, most bell like tone you can from each string. Sometimes this is a very subtle adjustment, a couple licks of a nut file in the right place.

It's hard (but not impossible) to do this work correctly without using gauged files made for this purpose. I have also heard of but will never try, gauged and ribbed tip cleaners for welding torches or feeler gauges that you modify by filing or grinding teeth along one edge. Needle files are used by some but I doubt if any professional repairers use them for anything except maybe bass string slots.

The correct tools for this type of work are expensive and not worth it for a one shot project. I would recommend that you take your mando to someone that is familiar with this type of set up work and save yourself some frustration.

[thefishinmusician]

Paul is correct..Chances are you will go to deep, too wide, not wide enough it may seem, and in trying to correct it.....boom...It bottoms out...Tis' truly a finnesse job..Best left to someone who's spent a lot of time messing up nuts to begin with, and over the years has learned that it aint not as easy as it looks!!

[Greengrass]

Thanks for the reply guys.
You've convinced me not to try this myself !!

Out of interest, I have also noticed that my E string is a little dull/dead compared to the others. Could this be caused by nut problems or could it be saddle related ?

Many thanks.
Greengrass

[thefishinmusician]

Is it dead as you fret it up the neck, or just dead when it's open?..ALOT of times, I get strings dead right out of the package..I have done some outstanding repairs by just putting a new string on!! I recently did a strat, and the low E string would not intonate correctly..I lowered the pickups, no help..Put a new string on...No help..Put another new string on and Bingo!! So that was 2 dead strings in a row..Allways the first thing I go to when the intonation points don't line up as the laws of physics say they should...

[Greengrass]

That's a good question.
I think it starts around the 10th or 11th fret but it's maybe just more obvious there.

I'll change strings tonight and let you know how that sounds :-)

Thanks again for the advice.
Greengrass