Mandolin kit build-loss of volume

[HD83]

Hi, finished a Siminoff kit build awhile back, mandolin was set up & played fine, good action and volume. After awhile action seemed a bit high up the neck and since action was good at first few frets and adjustable bridge was all the way down I figured taking material off the bottom of the bridge was the logical answer. I used 220 grit sandpaper lightly taped to top and carefully ran bottom of bridge back & fourth...wound up taking less than 1/16" off but when I strung it back up it just seemed to be quieter and a little darker/woofier, not drastically but still a noticeable difference. Just checking to see if that was a common thing after messing with the bridge? Other possible factors/causes?

[Willie Poole]

I am not a builder but have been told by a lot of people that I do a good set up on mandolins so here is what I think...

If you were using nothing but your hands to slide the bridge back and forth on the sandpaper you may now have a rounded bottom on the bridge base because a lot of times this causes a rocking motion on the bridge....Some people slide it side to side and some back and forth between the tailpiece and the fret board...One thing that I do is take notice of where the bridge is fitted as far as correct intonation and then remove the strings and sprinkle some powder on the place where the bridge usually sits, then press the bridge down on the powder real hard, them look at the bottom of the bridge base and it the powder doesn`t cover the entire length of the base then use a rounded knife blade scrape the powder off where it is on the base, those will be the "high" spots you might have to do this a few times but for me that always gets a perfect fit...Just work slow....I`m sure if you google a bridge fitting web sight you will find other suggestions as to correctly fitting a bridge...Check it real close to see if it is flush all the way across the top when you have it in place and under string tension...

Willie

[Dfyngravity]

A couple things:

1. Any time you take all of the string tension off of a mandolin for a while and then string it back up, there always seems to be a break-in period where the top acclimates to the string tension again. I find this particularly true if it is red spruce, though it doesn't last too long.

2. As you lower the height of the bridge, you are also lessening the string break angle. This in effect will put less pressure on the top which typically means less volume.

3. As Willie Poole suggested, check the fit of the bottom of the bridge to the top. Any gap will rob the mandolin of volume and tone.

I would check the fit, if everything seems good...just keep playing for a few days. You may find that the tone and volume come back as you play it. You may also want to try raising the saddle up a bit to get it back to the original height and see if that also helps.

[John Kelly]

A remote possibility, if all the other checks do not work for you. Could the neck itself have moved slightly?

After you finished building it perhaps the string tension over the time has caused the neck to distort slightly, so causing the action to be a bit higher further up the neck while not affecting the action near the nut. Did you fit a truss rod or other stabilising piece in the neck during the build? As I say, probably only a remote possibility, and more likely the bottom of the bridge is no longer as closely in contact with the soundboard. When shaping the bridge feet I generally use a cabinet scraper as it is so easy to sand an inadvertent curve into the foot as you move the bridge back and forth while sanding it in situ.

[pops1]

I use a scraper also, but I will also use the back and forth sandpaper to fit the foot. When I do the back and forth I will clamp a piece of wood across the top that only contacts the edges and is curved to not contact the top, but is a guide for the foot to keep it accurate. I also fashioned a piece of wood that sets on top of the screws of the bridge foot to give me something to hang onto and keep things in square.

Usually when I want to lower a bridge I will not take it off the bottom that I have already fit, but off the top of the foot. Sometimes a little off the saddle, but off the foot first.

[HoGo]

Another possibility is strings... They can go dead after loosening and then tuning up again...

[HD83]

Thanks for the feedback y'all!