Much as I dislike FB, from time to time there are good things. Here’s an excellent video of making a tuning hammer - since we often seem to discuss this matter here.
And here’s a useful and practical French-language ‘how to tune’ book, by Julian Wolfs:
Brilliant. Ugo Casiglia, who I have met once, is one of the very best Italian makers (not only harpsichords, but fortepianos and clavichords as well), and his son Claudio, along with harpsichord making, is charged with all things metal in the shop and they sell parts as well.
This is a method different from the one used by David Law. David makes a model probably in wood or resin, then makes a mould from the model and finally the foundry puts the melting bronze in the mould. Casiglia turns an iron bar on a metal lathe.
I like the bronze color more than iron, however.
Metal lathes are expensive, and nowadays they all are computerized or electronic.
In a 2009 Piano Technicians Journal article Ken Eschete gives a simple way to make a custom tuning hammer for a flat pin:
- drill a hole in the end of a length of drill rod
- heat the end of the rod to cherry red
- insert a tuning pin in the hole and hammer the rod flat to fit the pin
- reheat the rod to cherry red and quench in water
- make a handle for the rod