My daughter Eleri recently bought a 1921 Singer hand crank machine from a charity shop, in a generally lovely, and working condition. However the wooden handle was held on with a really nasty ill-fitting bolt and a nut with the wrong thread. It should be held on with a steel pin with a flat head and peined over at the arm end.
I decided to do something about it. A four inch nail cut to length, three small washers, and some time spent with a file, and a small ball pein hammer did the job.
I'm quite pleased with the result.
I just need to clean and oil all the bushes and bearings now.