Crawls Backward (When Alarmed)

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Installing a Maple Bridge Plate on the Kay K22 Guitar

Once I got the old spruce bridge plate off, I went to work on making a new maple replacement.

I used the old one as a template (not really hard, it was just a rectangle after all), and made the new one just a touch shorter.

Then I used carpet tape - the secret to holding stuff onto cauls and sanding guides - to stick the soon-to-be-bridge-plate onto my plywood sanding block holder thing.

Over to the belt sander and whoosh there you go.

I measured the thickness as I sanded, and here I am confirming the thickness I was aiming for: .090.  The piece of maple was .125, so I didn't take off that much.

It has a touch of flex to it, but nowhere near as much as the old original spruce on did.  Maple is cheap.  I'm still wondering why Kay used spruce instead.

In another bit of 'craftsmanship' (as if) that no one will ever see, I did a bevel on the edges. 

This is the only actual luthier-like touch on this whole project.  Otherwise, it's all my usual hack job.

I measured and marked the plate so it would be aligned properly under the top.  See the two red marks - they will line up under the two outermost string holes.

Also see the two beautiful cocobolo bridge blanks I used for cauls.  I covered one of them with waxed paper and then attached the plate to it with carpet tape.  The other piece will be the caul for the top side.

I love cocobolo!

There's a short working time with hot hide glue.  The working time can be extended somewhat if the mating surfaces are heated.  In this case, I stuck my heat gun inside the body for a few minutes, and I also heated up the new plate as well.

Then I spread the hide glue on the plate.  See why I put waxed paper on the caul?  The thought of that beautiful cocobolo getting stuck on the plate is the stuff of nightmares.

Using the alignment marks, I stuck the bridge plate into place.  One of the great things about hide glue is it has fantastic initial adhesion.  One I had the caul and plate in place, I was able to let go of it and grab a clamp.   Really nice.

I'm pretty sure Titebond wouldn't hold like that.

I used 5 clamps to hold the plate into place.  Again, waxed paper on the top under the caul.

Why did I use the cocobolo bridge plates?  I just happened to have ordered a few of them, and they were out on the bench.  I figured they'd be good cauls since they were already the perfect size and shape.  And that one looks darn good!  What beautiful grain.

Did I mention I love cocobolo?

Not a great picture, but you can get an idea of what the clamps look like on the inside.  This is looking into a mirror reflecting upward.

The next day after the glue is dry.  The mark to the right is where the old plate was glued.    There's a little squeeze out on the new plate - I'm not going to be able to reach it.  Looks pretty good I think.

This also gives you a good idea of the ladder bracing - the braces run across the top, unlike the more popular Martin X-bracing.

We'll see if it actually affects the tone, but in any event, I'm glad I replaced the old one since it was badly cracked and torn up.


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