Shaving bridge feet

[Dan in NH]

I have a Kentucky KM-250 that I bought from Elderly Instruments. They did a setup before they shipped it to me. The action near the nut is great, but at the 12th fret it’s a tad high.

When I took a look at the bridge wheels, they were already all the way down. So the take the action any lower I’m going to to shave the bridge feet.

Because the top is arched I can’t use anything flat to help me. I’m thinking I’ll take all the strings off, put a piece of sandpaper on the soundboard (paper side down), and run the bridge up and down a few times to take off ~3/32.

What grit sandpaper would be good?

[Bill McCall]

I don’t know if this is the ‘right’ way, but I’ve taken the saddle off and taken a little material off the flat that sets on the wheel. A whole lot easier than sanding the bridge down.

[HonketyHank]

I would use 100 grit to remove wood, then follow with 220 grit to smooth it out.

[pops1]

I have done what Bill suggests, it's much easier and will get the same result. You will lower the thread length either way, why not do it the easy way. If your saddle is tall you can also take a slight amount off the bottom where the wheel sits. Don't take much as it can weaken the saddle, tho many are plenty tall.

[EdHanrahan]

Sometimes "quick, dirty, & cheap" can work well, at least temporarily.

Sorry if this makes the pros among us cringe, but:
If you just take the thumbwheels out, the center flat area of the saddle should end up sitting directly on the center flat area of the base, which most folks would think is better "string-to-soundbox" contact than you get thru the standard setup. IF the action is now good, you're set to go, at least for the short run.

[Sue Rieter]

Advice that was given to me when I sanded mine was that you need to be sure you keep it upright so your bridge doesn't lean afterward. I made a little "handle" to set on top of the bridge and used a block of wood to keep it upright. What Ed suggested above was also suggested to me, but I didn't want to lose the adjustability. I'd probably try it if I had it to do over again. It took me days to cautiously remove material; an experienced repair person can do this very quickly.

[Tom Haywood]

What is the measurement at the 12th fret now? You are about to risk your bridge. Lowering the bridge 3/32" means that you are planning to lower the action at the 12th fret as much as 1.5/32. Low action is considered to be 1/32 on the high E string and 2/32 on the low E string. What are you aiming for?

A regular fix is to take wood off the bottom of the saddle. Not taking too much off and getting the wings and bottom square and level are the tricks. If possible, I like to set the low adjustment so that the saddle is sitting on the base. Saddles can split over time, so you want to take off as little as possible. If the post holes are open at the top, you may have threaded posts poking up to deal with.

If the feet are already well fitted to the top, I would be hesitant to take off wood there. I think you'll find that it takes a good bit more than "a few times" to sand down the feet even a little bit. Being sure that they fit the top well is essential or you will lose sound.

[Jonathan Ward]

This is one approach that works very well: https://youtu.be/-c9r6Nl0Yas

[Dan in NH]

What is the measurement at the 12th fret now? ... What are you aiming for?

I don't have exact measurements. I know I use a 1.5mm pick, and at the first fret I can't easily slip the pick between the strings and the frets. OR one of my old 1mm picks. So it's probably ~.75mm there.

Down at the 12th fret my 1.5mm pick slips right between the strings and the frets and falls out the other side. If I stack 2 1mm picks they slip right in, just touching the strings. So I'd guess it's about 2mm there.

I think I'd like to get the action at the 12th fret down to ~1.5mm

A regular fix is to take wood off the bottom of the saddle.

I googled this issue before I started this thread, and several sources advised specifically NOT to attempt to shave the saddle. They specifically advised to shave the bridge feet.

I've got a guitar tech I use, and he's done good by me for a lot of jobs different in the past. I guess I'll have him do it.

[Dan in NH]

I'm bringing my mandolin to a Wernick Jam Camp in a couple of weeks. I'll have some of the long time mandolin players there give my mando a gander, see what they think should be done.

Mick at The Music Techs in Manchester says on his web site that he'll do a mandolin set up for $80 plus strings. If the mandolin players at the Jam Camp agree that I need to bring my action down I'll just have Mick do it.

[Rob Roy]

I'm bringing my mandolin to a Wernick Jam Camp in a couple of weeks. I'll have some of the long time mandolin players there give my mando a gander, see what they think should be done.

Mick at The Music Techs in Manchester says on his web site that he'll do a mandolin set up for $80 plus strings. If the mandolin players at the Jam Camp agree that I need to bring my action down I'll just have Mick do it.

^^This sounds like a good idea, let some seasoned players/techs look at it first.^^

2mm is not outrageously high at the 12th fret. 1.5mm or down to 0.050" on the E string is a decent target if the frets and neck are in good order.

.75mm at the first fret is quite high though and will make the instrument much more challenging to play. It should be closer to 0.007" on the E string. Adjusting nut slots on a mandolin is a job best left to a tech/luthier with the tools and experience on mandolins, something most guitar techs lack. Have a great time in jam camp!

[Dan in NH]

I swung by Strings-n-Things in Concord. They had a few Eastman mandolins on the wall, and I gave a few of them a go. ALL OF THEM had a much lower action at the 12th fret than my KM-250.

I'm not going to monkey with my mandolin this close to Jam Camp, but afterward I'm definitely bringing it somewhere for some work.

[Dan in NH]

I also think I'm gonna drop down from 11-40 to 10-38.

[Sue Rieter]

Hey Dan, your fingers might thank you if you change your strings ahead of time