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Yankulele
11-05-2015, 05:11 AM
Hi all,

What techniques can you recommend for building relief into a finger board, and, specifically, how much relief, and where do you locate it?

I am working on my first bound finger boards, and my plan is to either sand or scrape the back of the (tenor) finger board so that when I glue it to the neck, the relief will be there. I have a carbon fiber bar (1/8 x 5/16) on edge in the neck to keep it stable over time. I know the relief wants to be small, 5 thou? 10 thou?, and I know it should taper, but I am not clear on what a good amount would be and where to start and end the taper.

Thanks for your advice,

Nelson

sequoia
11-05-2015, 06:54 AM
My fretboards are tapered 1 3/8" at the nut to 1 7/8" on a 19 fret tenor... I'm not familiar with putting relief into the fretboard. I would think this would make fretting very difficult as the frets over the "relief" would be higher. My fretboards are perfectly flat. Or perhaps I'm not understanding your question. Maybe you mean "neck relief" instead of the fretboard relief?

Beau Hannam Ukuleles
11-05-2015, 07:06 AM
Sand the fingerboard in the middle for 5 seconds

ksquine
11-05-2015, 07:26 AM
You'd have to sand it into the neck somehow and then glue on the fingerboard. There just isn't enough string tension in a ukulele to get neck relief like in a guitar. If you scrap the back of the fret board, it will just flatten out when you glue it to the neck. I'm not sure about your neck length...but its probably around 9" nut to body joint. To get a 0.01" relief you're basically bending or sanding the neck into a 337' radius!!
radius = ((arc height)^2 (arc length)^2) / (2* arc height)

Usually the action on a uke is high enough that relief doesn't really matter in playing feel.

Hluth
11-05-2015, 08:00 AM
I use a scraper to put about four thousands relief centered under the 5th fret (the thickness of a sheet of copy paper) before gluing on the fret board. Progress is checked by holding the neck with a straight edge against the surface up to a light. The reason for relief is to prevent possible buzzing (commonly on frets 3-7). The relief provides a little more space between the next fret and the string as you play up the fret board.

RPA_Ukuleles
11-05-2015, 10:34 AM
Really depends on when you fret. If you fret and dress before glueing on the fretboard, sand/scrape relief into the neck or to the back of the fretboard. Or do like Maya Moe and tension the neck while glueing the fretboard. But if you fret dress and level after the fretboard is on, then sand it into the board after attaching to the neck. Just don't level the frets with a long sanding bar after. You would lose the relief you just put in. Center the relief under the 5th or 6th fret and taper "nicely" in both directions. Don't really need to be too much more specific than that.

Michael Smith
11-05-2015, 10:44 AM
Kala builds in a very dramatic relief on their necks at least a few I have seen. It's got to be 25thousands or more.

Yankulele
11-05-2015, 12:23 PM
Thank you all for your help. It was just the information I needed. I have scraped in about 4 thousandth centered on the fifth fret. I plan to fret before gluing on the finger board, and will make a caul with matching relief for the glue up.

Nelson

aaronckeim
11-05-2015, 02:51 PM
At Mya-Moe we build .005 of final relief into our necks and fretboards. We have a carbon rod in the neck, but we flex the neck and use a special caul to glue the flat board onto the flexed neck. We also keep the fretboard in a caul overnight so that it is flexed the right way when it goes on. Somewhere in the Birth Of A Mya-Moe videos you can see all the cauls and techniques, somewhere around step 6. I'm not sure which video, you will have to look for it: http://www.myamoeukuleles.com/videos.php

Yankulele
11-06-2015, 01:17 AM
Thanks, Aaron. I will check out that video. I've watched a lot of your videos, and think they are great. I have already learned a lot from them. Also love the finger style book.

Nelson