There's no serial number on some of the less expensive older Gibsons. Instead it has a Factory Order Number. The first letter 'W' tells us the year. This number is not unique to the instrument but to the batch that was made at the same time.
It came into the workshop because the bridge pins were sitting wonky and the guitar was hard to re-string.
This is a picture taken of the inside of the guitar using a mirror - the ball ends of the strings have dragged their way through the wood. But the main problem is the bridge plate. It was fitted in the wrong place - someone at Gibson must have been having a daydream, made the bridge plate too small but stuck it in anyway.
This diagram shows what it should look like. Although this is of a Martin the principle is the same.
So I decided to remove the existing plate and replace it with a new one. The bridge is bolted as well as glued on. As the bolts go through the bridge plate they need to be removed first. The bolt heads are hidden under two mother-of-pearl dots. I push the bolts out from inside and pop the dots out.
The whole guitar is constructed using heat reversible glue so to remove the plate I can soften the glue by warming it up. I only want to warm up the bridge plate - the adjacent braces are also attached with the same glue and I'm keen not to get them too hot.
To localize the heat I use an iron which I warm up using a heat gun. As you can see its made from an old Strat neck plate with a wooden handle.
I moisten the bridge plate with a sponge and very carefully using the iron heat it up.
Its rather tricky and very easy to damage the guitar and burn your hand.
It takes time and patience. When I feel it is hot enough I can start to prise the plate of using a bent 6" ruler. There's more heating and more easing - it can take a while. I want to get the plate out in one piece. This photo is taken using a mirror inside the guitar.
Finally the plate is out cleanly.
I can now make the new bridge plate. I can use the old one to get the angle of the sides right. I'm using a rather nice piece of flamed maple I got from Adrian at Ash Customworks (www.ashcustomworks.com/) - I didn't happen to have any maple and he was kind enough to help me out.
Once I'm sure its the right size its ready for fitting. I tape a plastic covered piece of plywood to the underside to prevent the clamps from causing any damage. The plastic ensures the ply doesn't get glued to the bridge plate.
It is now glued and clamped in place using animal glue of course - that's what Gibson used.
Here's the finished job - the pegs sit straight and the string ball ends have a positive anchor point. You can hear the difference in how focused the sound is.
Finally after 55 years she gets a proper bridge plate. Lets hope this guitar is still in regular use in another 55.
Glyn
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I am no longer repairing guitars - since covid 19 I now work full time making pickups
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