String wear on bridge

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Quinny
Myrtle
Posts: 74
Joined: Mon Oct 06, 2014 1:16 pm
Location: Box Hill, Melb

String wear on bridge

Post by Quinny » Sat Aug 04, 2018 4:41 pm

Hi there, ( images below)

I have a tenor uke with bridge wear from two strings, mainly the 'A' string being the thinnest. It is a tenor uke I made 3 years ago with a cedar soundboard. The neck is walnut so I thought I'd make the bridge from walnut. I thought it would be hard enough. Looks like I was wrong. Must be why ebony and rosewood is used.

I have thought of the following possible repairs but don't know of the risks of future failure:
- I wondered if I could sand down a little of the back of the bridge that is wearing and insert bridge pins, which I have done once before and have the reaming tool.
- Or maybe sand down the wearing back section of the bridge to the height of the side wings and glue on some ebony and re-drill holes for the strings. But would the glue between the walnut and ebony be a strong enough bond?
- remove the bridge entirely and put another one on (unfortunately I have had to do that before and know how to do it after seeking previous advice from this forum).

My queries please:
- Should you only ever use ebony or rosewood for a uke bridge?
- Any advice on the best option to proceed re the worn bridge - either my suggestions or any others you have.

Any recommendations appreciated

Thanks
Quinny
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bridge wear tenor.jpg

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kiwigeo
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Re: String wear on bridge

Post by kiwigeo » Sat Aug 04, 2018 5:50 pm

On my classicals I always fit bone strips along the front and back edges of the tieblock to prevent what is happening on your uke. It shouldn't be too difficult to retrofit some strips of bone along the edges on your bridge...I certainly don't think your issue warrants removal of the bridge. Its a simple matter of routing channels along the front and back edge of the tieblock and then supergluing the bone strips in. If the top of the tieblock is badly damaged then shave off the damaged top of the tieblock and then glue on a layer of wood to replace the wood youve removed before fitting the bone strips.

Alternately you can fit a single thin layer of bone over the entire top of the tieblock to achieve the same function.
Deluxe_Ukulele_Bridge.jpg
Deluxe_Ukulele_Bridge.jpg (13.7 KiB) Viewed 197 times
And here's Robbie with a tutorial on how to fit bone protector strips to a bridge tieblock: https://youtu.be/LPIkzgXLyWo

Quinny wrote:
Sat Aug 04, 2018 4:41 pm
Hi there, ( images below)

I have a tenor uke with bridge wear from two strings, mainly the 'A' string being the thinnest. It is a tenor uke I made 3 years ago with a cedar soundboard. The neck is walnut so I thought I'd make the bridge from walnut. I thought it would be hard enough. Looks like I was wrong. Must be why ebony and rosewood is used.

I have thought of the following possible repairs but don't know of the risks of future failure:
- I wondered if I could sand down a little of the back of the bridge that is wearing and insert bridge pins, which I have done once before and have the reaming tool.
- Or maybe sand down the wearing back section of the bridge to the height of the side wings and glue on some ebony and re-drill holes for the strings. But would the glue between the walnut and ebony be a strong enough bond?
- remove the bridge entirely and put another one on (unfortunately I have had to do that before and know how to do it after seeking previous advice from this forum).

My queries please:
- Should you only ever use ebony or rosewood for a uke bridge?
- Any advice on the best option to proceed re the worn bridge - either my suggestions or any others you have.

Any recommendations appreciated

Thanks
Quinny
Martin

Quinny
Myrtle
Posts: 74
Joined: Mon Oct 06, 2014 1:16 pm
Location: Box Hill, Melb

Re: String wear on bridge

Post by Quinny » Sat Aug 04, 2018 7:37 pm

Sounds like what I need - kiwegeo. Quick question. Does that mean I redrill the hole for the strings below the bone inserted into the rebate?

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kiwigeo
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Re: String wear on bridge

Post by kiwigeo » Sat Aug 04, 2018 8:33 pm

Quinny wrote:
Sat Aug 04, 2018 7:37 pm
Sounds like what I need - kiwegeo. Quick question. Does that mean I redrill the hole for the strings below the bone inserted into the rebate?
It depends how far below the top of the tieblock the holes are....on a classical bridge there's normally a far bit of meat between the holes and the top of the tieblock. The bone strips I use on my tieblocks are 2mm x 2mm thick. You can always work them down thinner if you need to.

My course of action would be as follows:

1. evaluate damage to top of tieblock.
2. If the rut cut into the tieblock is deep then shave top of tieblock until damaged wood is removed.
3. Glue on a strip of wood to top of tieblock and trim sides and top.
4. route channels on front and back edge of tieblock. Adjust channel depth to clear string holes and to allow a bit of overhang when glued in to allow for sanding of the bone back flush with tieblock sides and ends.
5. glue in bone strips with CA (I use hot stuff low viscosity CA)
6. Sand back bone strips flush with top and sides of tieblock.
Martin

Quinny
Myrtle
Posts: 74
Joined: Mon Oct 06, 2014 1:16 pm
Location: Box Hill, Melb

Re: String wear on bridge

Post by Quinny » Sun Aug 05, 2018 5:52 pm

Sounds perfect and clear instructions (kiwigeo). Thanks for taking the time.
Quinny

Quinny
Myrtle
Posts: 74
Joined: Mon Oct 06, 2014 1:16 pm
Location: Box Hill, Melb

Re: String wear on bridge

Post by Quinny » Fri Aug 10, 2018 6:59 pm

Just making a new bridge for a baritone uke, and will also need to repair the tenor uke with the wear that was originally pictured.

Any advice on how to best make a channel for the bone edges either side of the tie block. I have to do it on the bridge already fixed to the tenor, but the baritone I am making is not glued on yet.

At my disposal I have a router and table, circular saw and table, as well as a Dremel and small router cutters. But thought maybe hand tools are better??

Thanks
Andrew

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kiwigeo
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Re: String wear on bridge

Post by kiwigeo » Fri Aug 10, 2018 7:46 pm

1. For bridges that are off the guitar I sit the bridge in a jig and cut the slot with a Trend T5 router with a fence mounted on the base plate. I use a 2mm double flute straight cutter for the saddle slot and "valley" between the tieblock and saddle ramp and for the saddle ramp I use a 45degree bevel cutter.
IMG_0345.jpg
IMG_0359.jpg
2. For bridges fixed to the instrument I use a Dremel and a Stewmac jig - https://www.stewmac.com/Luthier_Tools/T ... g_Jig.html



Quinny wrote:
Fri Aug 10, 2018 6:59 pm
Just making a new bridge for a baritone uke, and will also need to repair the tenor uke with the wear that was originally pictured.

Any advice on how to best make a channel for the bone edges either side of the tie block. I have to do it on the bridge already fixed to the tenor, but the baritone I am making is not glued on yet.

At my disposal I have a router and table, circular saw and table, as well as a Dremel and small router cutters. But thought maybe hand tools are better??

Thanks
Andrew
Martin

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