Bridge thickness questions

finkdaddy

finkdaddy

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While shaping a bridge for a uke I'm currently working on, things got a little out of control and it came out very thin. I can't remember what it measured to off the top of my head, but it can't be more than 3/16" thick, probably closer to 1/8". Even though the slot is pretty shallow, it does hold the ebony saddle tightly. Also, I will be drilling holes through the bridge and securing the strings on the inside of the soundboard (I don't know what that method is called).
Assuming that my string height and saddle height all work out, will this be ok? I do not have any angle on the neck/sound board. They are both flat, which is why I was thinning the bridge in the first place.
Other than supporting the saddle and holding the strings, is there other functions that the bridge provides?
How thin do you folks go on your bridges?
 
Since you said there is no angle on the neck/soundboard, this means the fretboard surface is parallel to the sound board surface.
You could lay a ruler flat on the fretboard, starting from the nut, extending to the bridge. The ruler should be right on top of the bridge (without saddle).
If there is a gap between the ruler and the bridge, the bridge is too thin.
If the ruler got lifted up by the bridge, then the bridge is too thick.
Typically the fretboard is 1/4" thick, and its extension should lie perfectly flat on the soundboard. This means the bridge has to be 1/4" thick.
If the bridge has to be thinner or much thicker than 1/4" to meet the ruler alignment described above, then the neck has an angle.
www.frets.com has an article + photos describing this topic in very details.
 
I would never make a uke fingerboard 1/4" thick, that's guitar thickness. I think 1/8" to 3/16" would be for fitting.

The bridge style you describe would never work with a 1/8" thickness. There isn't going to be enough meat to hold the saddle upright for long. The saddle will start to lean in no time unless the saddle and bridge are all one piece of wood. Even then, it depends on the saddle height.
 
My mistake, I have always thought that the fingerboard of the tenor uke I am building is 1/4" thick, it's between 3/16 and 4/16 (7/32), just go measure it.
It came that way in the kit. In the post#2 above, just replace 1/4" with the thickness of your fingerboard. The ruler method still applies.

I have a question: is there any downside with my uke that has the fingerboard thickness greater than 3/16" ?
From the strength point of view, it will make the neck more stiff, but I have no idea about its effect on the sound.
I just glued the bridge on today, tomorrow I will know its sound.
 
A thick fingerboard will add more weight and mass making the uke a little head heavy. The extra wood is not needed. As for additional strength, that would be negligible IMO. I find that a good solid neck to body joint plus the addition of a carbon fiber truss rod will provide the best stiffness and strength.

When building from kits, it is best to remember that the woods come over sized and aren't always meant to used as is out of the box. Having said all that, your uke will probably come out fine. Refinement comes with experience, good luck.
 
On a tenor uke with a flat fret board I make mine no more than 3.5mm thick. If it's got a 12" radius on it then it starts at 4.5mm in the middle, and the sides come down to that 3.2 to 3.4 range. Just enough room to install side fret markers.

A 1/8" tall bridge is doomed to failure in my opinion. If indeed it's going to need to be that slim, then I'd be looking at incorporating the saddle as part of the bridge. Not cutting a slot for a bone one, but making the entire bridge / saddle combo out of wood.
 
I wouldn't use that bridge. The saddle will end up being too tall and lean forward
Either start a new bridge or maybe glue another piece under to add thickness. I'd just start over fresh
 
Wow, a lot of great info here! Thanks everyone. :)
I've already started making a new bridge, so that is covered.
Now I realize that my fretboard is too big too.
Oh well.

Allen, if a tenor fretboard is 3.5mm thick, does your bridge match that?
 
Is it a scratch build? If so, you really need to draw yourself a side view of your instrument before you start building. The drawing allows you to check the fretboard thickness, neck angle, bridge thickness, break angle, string height over the soundboard etc all before you start.
 
No, I build with a radius in the lower bout and the neck is set. My bridge ends up being between 7.0 to 7.5mm tall. I aim for bottom of strings to soundboard in front of the bridge to have a hight of around the 10mm mark once the action is right at nut and 12th fret.
 
liam_fnq said:
Is it a scratch build? If so, you really need to draw yourself a side view of your instrument before you start building. The drawing allows you to check the fretboard thickness, neck angle, bridge thickness, break angle, string height over the soundboard etc all before you start.
Click to expand...

Yes, it is a scratch build. That is a very good idea. I've started drawing up some plans so that I can duplicate things from one uke to the next.
Thanks.
 
When building from kits, it is best to remember that the woods come over sized and aren't always meant to used as is out of the box. Having said all that, your uke will probably come out fine. Refinement comes with experience, good luck.
Click to expand...
This kit I bought is basically all raw woods, except the fretboard slotted for 17" scale and the side bent.
I have to cut everything to shape and size, but did not thin down the fretboard (I don't even have the tool to do this operation either). Very close to a scratch build. The top and back board thickness remain as they arrived. I cut the bridge myself and make sure it has the same thickness as the fretboard to meet the "ruler method" requirement.
 
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