This is a lovely old guitar that came to me with an unplayable action. 12 string guitars often suffer from problems related to string tension and this one had really suffered. The top was bellying and needed the bridge plate replacing - I'll go into that one at a later date. Even with the top stable and the belly reduced the action was still too high. The bridge saddle was right down low so it wasn't going to be an easy one.The neck had to be re-set. Over years the neck had moved with string tension and was now leaning forward a little. This was giving the guitar too high an action. There are a few ways to re-angle a neck; the traditional way is to completely remove the neck from its socket and re-cut the dovetail joint to the correctangle. The main problem with this is damage to the finish around the heel. I chose a different way - its called 'slipping the block'. With this method the neck stays in the body and the back of the guitar is removed (peeled away) between the guitar's shoulders. Once the back is seperated from the block the neck becomes 'wobbly'. The back can then be clamped in place with the neck at the correct angle. Ok, so here's how its done. First the binding had to be removed so the back could come off cleanly. I scrape the finish away from the binding with a blade - if I left it on it'd crack and make a mess when the binding came off. Then the binding can be peeled away carefully using the blade.
I don't take it right off, just as far as the shoulders. Guitars are always put together using heat reversable glue which means if you warm them up they come apart. To seperate the back I use heat lamps which gently warm the glue from the back. If it gets too hot the finish can get damaged so its a gentle slow process. When I feel its warm enough I start pushing a spatula into the joint to ease it apart. Push too hard and the wood can split - too soft and nothing happens. In this pic the green tape is holding the binding out of the way. A butter knife is just great for this job.
When the back's off its time to get the action right. I put two E-strings on the guitar and a bridge saddle of the ideal height. Then I clamp the guitar from bum to heel. As the clamp tightens the action lowers.
The back will now be overhanging the sides a little so it needs trimming before the binding goes back.
There's no easy way to re-angle a neck but for me this is the easiest.
Feel free to contact me about repair work (if you are in NZ). I only check emails weekly so the workshop phone is always the best 09 307 6501.
Mr Glyn’s Guitars
21a Khyber Pass Road
09 307 6501, 021 912678