Tuesday, April 19, 2011

Mandolin set up part 2

Ok so the first time I changed the strings on my mandolin, I decided to flatten out the bottom of the top part of the bridge as it didn't mate right and I knew it would lower the action. So I did that. But the action was still on the high side so I did some surfing and found that I should remove material from the bottom of the bridge where it meets the face of the mandolin and raise the turn wheels up until I had the right string height. Well I found out that it is a lot harder to do. But none the less I was determined to do it.

So first I marked the position of the bridge with a piece of electrical tape on the body forward of the bridge, and I lowered the tension on the strings so that I could flip the bridge forward onto the tape and remove it without scratching the finish. Then I scribed along the bottom of each foot on the bridge a mark of how much material I wanted to remove. slowly with some sand paper on the edge of a table I sanded until I met the mark and matched the radius of the face. But I had to keep working it until I couldn't see any gap on either side. I didn't want the bridge to put uneven pressure on the face of the mandolin. That process took over 2 hours.

Then I used the turn wheels to raise the top part of the bridge until there wasn't any fret buzz. I was getting just a little on the D string. I had to bring the strings up to pitch and back down again a couple of times and turn the wheels. I coudln't turn the wheels with the strings under tension. I finally got the height to what I read online was ok. .070 inch on the G string above the fret at the octave and .060 on the E string.

Now this cheap import is about as good as it's going to get. There's no fret buzz and it really did improve the intonation. Over the weekend I replaced the strings with D'Addario J73 Phosphor Bronze Light ones. That seemed to help the intonation a little too because I could hear the harmonic overtones better and that helped tuning.

(photo will get bigger if you click on it)


Jules said...

Alot of hard work, but I'm sure you're happier with it now than you were before. Sure wish we could have won that other one though... :)

don said...

Oh well, I'll get a better one at some point. This one will do for now.

Quiet Paths said...

Good job! Bet you learned a lot. I watch Matt do this all the time to different pieces.

don said...

Yes I did learn, but Im not sure I'd do it on an expensive mandolin. I figured I had nothing to loose on this cheap one.

I'm finding out that Mandolins are either really expensive or really cheap and not much inbetween.

When I upgrade I hope to get one that's already set up. But for now this one is ok.

Quiet Paths said...

That is a very good observation about Mandolins in particular. Why is that? I bought Matt a cheapie a long time ago and let's say it doesn't have any strings on it right now.

don said...

From what I understand it's because mandolins are so difficult to build. Harder to build than flat top instruments. They are like a violin in that the tops and the backs of are hand carved to shape like a violin. Plus they are under a lot of pressure when they are strung up. I think more pressure than a violin, and violins have a sound post for support.

A good mandolin is a lot like a good violin in many ways, not to mention that they are strung exactly the same.

You can get a celtic mandolin with a flat top from a good maker for much less money than a carved top one, but they don't have the "bark" or projection that a carved one does and don't work well for bluegrass. That's why the old flat top Martin mandolins aren't that expensive or popular.

Really low end mandolins have formed laminated tops and backs. And the carved imports like the one I have usually have other quality issues.

What I'm finding out is that probably the best import these days are the Eastmans from China. Eastman also makes violins. So there's probably an Eastman in my future. You can get a decent Eastman F style for between $700 and $1000 for their cheapest F model. The Cheapest Weber F from Montana is around or over $2000