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hi all
on a string through bridge (think Lowden etc. or external metal pined)
what purpose does the bridge plate serve?
and does it have to be standard shape / size / thickness.
just asking.
thanks
Geordie

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On a steel string, it gives some under-top support, to keep the bridge from pulling directly against a portion of the top that isn't supported by braces. The corners of the bridge may cross the X, but most of the torque is in the center, where the strings are. The bridge plate, from what I understand, sort of , ties the bridge to the X, and gives a stiffener under the top, to help support the top against the stress of the torque of the bridge. On a classical, you don't have the same issues, as you, mostly, have multiple fan braces that cross under the bridge, that provide the support against torque. Also, the string tension is not even comparable.

Don't pay any attention to this post - I'M A BEGINNER!

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Waddy

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There are those who would say you don't need a bridge plate on a pinless bridge, but I would use one. I agree with Waddy that the plate provides significant support to the top, especially right in front of the bridge, where it's pushing down. A reasonably thin plate with beveled edges will flex some, so it helps distribute that load over a wider area.

I also believe a bridge plate plays an important role in stabilizing the top's cross-grain expansion and contraction (with changes in wood moisture content) under the bridge, helping to maintain the shape of the top and keep the bridge glued on for the long haul.

Plus, if you put one in, you can switch to a pinned bridge in the future, if you decide you don't like pinless bridges anymore (a conclusion I've reached, myself), without having to retrofit a bridge plate.

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Todd Rose
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