Bridge Patch?

Laidback1

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Is there any need for a bridge patch on the inside of the sound board if the bridge is going to be a tie-block (classical style) bridge?
I can't think of a structural reason for it but wanted to bounce it off others more experienced.

Thank!
 
My understanding is that you only need that for pin bridges. (I have not put any bridge patch on the ones I have made, and that is even for longer guitar-scale-length instruments which would have more string tension than even a normal baritone sized ukulele).
 
Is there any need for a bridge patch on the inside of the sound board if the bridge is going to be a tie-block (classical style) bridge?
I can't think of a structural reason for it but wanted to bounce it off others more experienced.

Thank!

What sized uke are you making? Soprano? Tenor? It depends. Generally speaking, sure a bridge patch is a good idea. Not hard to do and gives you some added structural integrity by distributing the load. I always thought there are other issues with the sound board that are more important so just do the bridge patch and move onto the bracing where things actually really matter. I make mine about as thick as the top with a smidge extra. Say a 0.1 inch and cross-grained to the top. Good luck!
 
For crying out loud. A bridge patch is used for a lot more reasons than just if the strings go through the soundboard.

Look at the footprint of most that specified in plans or used in factory instruments. Do you honestly think that has no other effect than something for strings to pull up against? If you opt not to use one, you should at least know what you will need to do in order to compensate for it's absence.
 
If you Google "ukulele soundboard bracing" and look at "Images" you'll see lots of different ways of bracing a soundboard.

Apart from the transverse braces above and below the soundhole, for a soprano, the most commonly used pattern is probably just a bridge patch. For a concert its probably a patch and one or two fan braces and for a tenor a patch and 3 fans. But among all these possibilities there are many without a bridge patch.

The soundboard needs to be light and of the correct flexibility/stiffness. It also needs to be strong along the length of the box to counter the pull of the strings. So bracing is about achieving the required reinforcement for minimum weight whilst also enhancing transmission of sound across/along the board. Different bracing patterns enhance different modes of vibration and hence the sound of the instrument.

For many a bridge patch (with grain running at right angles to the soundboard) is a key element of bracing to assist in strengthening and transmitting sound across the soundboard.

There's much variation in all elements of bracing. Some will use a long, narrow and thin patch: others a shorter, wider thicker patch ....etc. Its the same with fans: some will use same height along the fan, others have a high point below the bridge or between the bridge and the soundhole.

To summarise, a bridge patch may be part of the whole soundboard bracing. Its presence or absence will determine the requirements for the rest of the soundboard bracing.

As an amateur maker, soundboard bracing is something with which I am constantly experimenting.
 
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A bridge patch is sometimes sized larger than the bridge width to reduce the stress riser at the edge of the bridge. It can reduce the amount the sound board bens where the bridge stops. This may help the bridge remain glued on, this also depends on the size of your bridge. If the bridge has a large footprint and the stress is low across it there is less need for a bridge patch to mitigate the bridge peeling up. Otherwise the bridge patch can be seen as part of the bracing scheme (which it would also be if used to help the bridge from peeling off) and modifying the way the top vibrates.
 
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