The above image shows my progress with the Bergerault vibraphone over the last three days, from the left; prime, undercoat, top coat.
This is the moment, before I put the new note rails into the instrument, to sort out any problems with the inner two note rails.
Unsurprisingly, these rails were also loose. Like the original outer rails, these also have a single tenon towards upper side of the rail. This is supplement with a tiny bracket at the bottom.
As Paul the Porter pushes the instrument at the top, there is greater friction at the wheels making the instrument rock from side to side. The leverage exerted by the very long rails on four octave instruments is enough to break open a single tenon joint, especially if it is located at either end (top or bottom). Again this is a design flaw; a demonstration of a lack of knowledge, forethought, and expertise.
I go to museums and see objects made literally hundreds of years ago that demonstrate the type of joint needed to resist a particular force.
Once the glue is dry on the inner note rails, I can then glue in the outer rails.
If you look very closely at this end of the outer note rails, there are two holes. This is an idea that I ripped off those museum pieces. It’s called a pegged tenon joint. Back in the day, they would have used a wooden peg, today I use a big screw. This screw ensures that the tenon cannot be pulled out, and massively increases the strength of the joint – why wouldn’t I do it, it took less than five minutes.
At the end of the day, I will remove the clamps and do one final coat of paint so that it will be finished for the final assembly.
This post continues in 1214: Bergerault vibe (part 4)