Spruce bridge plate

Restoring old ladder braced guitars like I do can be educational. The history of bridge plates for example. In the beginning in the 1800's there was no such thing, no reinforcements at all round the string pin holes. The knots tied on gut strings was kind of soft but the spruce did wear out around the holes.

The next step was a very thin square of maple just big enough to cover the area around the holes. Hard enough for gut strings knots, but to weak for steel bullet ends.

In the old days the bridge was not rectangular at the ends, the thin flexible ends of the mustache bridge is in fact a great way not to have a starting point for a crack. With the arrival of the rectangular pyramid bridge the bridge plate grew in width to pass the edge of the bridge and counteract the sharp and crack induction bridge ends. That's my theory anyway.

The next step was to extend the bridge plate even more covering the whole width of the top. Now the bridge plate could fight the rotation force from the bridge.

One thing was not considered in this evolution, the tone of the guitar. Especially the top wide bridgeplate is really bad for the tone, it leaves nothing but the middle range sound of the strings.

I came across a guitar with a double brace cut from one piece of spruce under the bridge with a flat spruce part in the middle acting as a bridge plate. The sound was very good indeed, the tone had a depth and a beautiful and varied tone that was new to me. I started to think that the top should not have any other wood than spruce on the inside, no maple bridge plate. I tried an all spruce bridge plate and to me the sound of the guitar improved a lot. The sound became softer, more detailed and more interesting.

On ladder braced guitars I do a "cross" with spruce and small hard wood reinforcements around the pin holes to cope with the wear from the steel bullet ends. I think maple is too soft so I use really hard wood for this.

I do it like this because spruce is much stiffer in one direction. The top part of the cross travels beyond the ends of the bridge to give a soft transition and avoid cracks. The middle part counteracts the rotation force with the spruce as stiff as it can be with the grain parallel to the top's grain. The length of the middle part can be made as long as needed to counteract the rotation force.

I use the Stewmac bridge plate repair tool to make the hard wood reinforcements around the string holes.

I'm very pleased with this spruce bridge plate on ladder braced guitars. It's light and strong. And above all, the sound is better than with a big maple bridge plate. Nothing beats spruce IMHO when it comes to tone.

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