Filing the Bridge Slot

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Hi everyone...

Quick question. Went to put some Koolau golds on my Koaloha concert, and everything was fine until I went to change the A string....the string is too thick to slide into the bridge slot. I've never done any work on a uke, so I'm wondering if there is anything special involved in filing the slot wider...

....I guess what I'm saying is, how the heck do I do it? I'm worried about doing anything to alter this wonderful instrument.

Thanks in advance!
 
Do you mean the nut? I have seen some bridges with slots and no saddle, but it is pretty rare.

I'll assume you DO mean the nut. The difference in string width will be very slight, so the amount of material to be removed is TINY. Emery boards, as used for filing finger nails, will probably be too thick, but you could try stripping one. Alternatively, try a piece of medium, or fine sandpaper. Keep the surfaces vertical, and only widen the slot just enough. Good eyesight is required.

Ukantor.
 
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DIY tip:

Other tools that can be used as erstaz nut/bridge slot files include the cleaning tools for O-A welding torch nozzles. They come in a set of varying gauges.

Also, lengths of wound guitar, mandolin and banjo strings in various gauges can be used if you get the technique right. Pulling the strings back and forth through the slot will widen it and give a nice rounded bottom to the slot. Beware of exerting a lot of downward pressure if you just want to widen the slot rather than lower the action.

Also, when working on nut or bridge slots, take care not to lose the slight downward angle of the slot away from the playable part of the string. That slight slope is there to give a nice clean "break" over the leading edge to ensure accurate intonation and avoid buzzing.
 
I've seen many Ukes with bridge slots. They're commonly used instead of bridge pins or classical style tie blocks.

I'd get an Xacto razor saw from Radio Shack and carefully work it through the slot. The saw is thinner than what you need so there's no (okay, very little) risk of making it too wide. Just work it back and forth in the slot, file style, until the string can slip into place and be held by the knot.

Here's a picture I found of a Koaloha Concert bridge:
Concert_006.jpg
 
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Oh, those bridge slots! :eek:

Yup, I have a soprano with those. Prefer a tie-bar.
 
DaveVisi, that's the one. That pesky A string slot is super thin. I've used an Xacto blade to build models as a kid, but I've never heard of an Xacto saw. I will call Radio Shack to inquire about it.

My initial idea was sandpaper. Maybe doubling up a piece and sliding it in there? I have no idea how that would work. I guess I'm just going to have to give it a shot, but carefully, oh so carefully. It seems like it would be silly to bring it in to a repair shop for such a minor issue.

Thanks to everyone who replied for the assistance!
 
DaveVisi, that's the one. That pesky A string slot is super thin. I've used an Xacto blade to build models as a kid, but I've never heard of an Xacto saw. I will call Radio Shack to inquire about it.

My initial idea was sandpaper. Maybe doubling up a piece and sliding it in there? I have no idea how that would work. I guess I'm just going to have to give it a shot, but carefully, oh so carefully. It seems like it would be silly to bring it in to a repair shop for such a minor issue.

Thanks to everyone who replied for the assistance!

The razor saws I have are only .10" thick, much to narrow for your needs. Exacto actually makes a small saw blade (looks like a keyhole saw about 2" long) that is exactly .025" wide which is closer to your needs. Make sure you protect the sound board by taping on a piece of cardboard before you start cutting or you'll be posting again with a different question!
Good luck
 
Eh, the more I think about this the more I am inclined to just bring it in. There are no uke shops around, so I'd have to bring it to a guitar shop. The idea of Guitar Center working on my ukulele is perhaps the scariest thought of all.

Or, maybe I'll just put the Worth strings back on there.
 
It's not that hard. The Guitar Center guys (unless they have a real pro shop) are probably no more experienced than you are. Sandpaper runs the risk of rounding the edges around the slot. Someone suggested using a wound string to work like a file for the nut. It'll work the same, probably easier because it's wood, on the bridge. Just run it back and forth until the string fits. It shouldn't take much.
 
The wound string idea sounds good. I guess I'd need a pretty thin gauge wound string. I think I'll have a look around the house to see if I have anything that will work.

Okay, thanks for the encouragement!
 
Success!

Update: I ended up successfully widening the bridge slot, using a regular razor blade. I was very careful and just sort of sawed back and forth until the string fit in there. Thanks again for the help; I wouldn't have had the courage to try it without your collective assistance.
 
Awesome that you fixed it! And your sandpaper idea would also have worked. Thats what I use whenever I need to widen a nut or one of those bridge slots.
 
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