It's not been a good day today. I bored the top plate to take a steel bush for the spindle to run in. I then started on the bush, I managed to make the OD undersize and the ID oversize! So I started again, I was lucky to find that I had a piece of steel just a few thou oversize, but I am fed up with having to hacksaw through 40mm dia. bar (next project, power hacksaw)
I completed the bush correctly this time, a press fit into the top plate and, at the moment, a tight fit on the shaft. Tomorrow I will lap it to fit.