The hardest oak I have ever worked with was an 'orphan' piece from the Mary Rose, which had spent some 450 years on the seabed. Dad was asked to make some presentation items from it, and I helped him. It was like working with iron - ordinary woodworking tools just wouldn't touch it!
Les
And nobody even mentions Rudolph's second-in-command, Dimbo, the brown-nosed reindeer. He's just as fast as Rudolph but not quite so hot on the brakes.
As promised, here are some book extracts which might be helpful. The first pages are from Chemistry for Organised Schools of Science, Parrish, 1899. The last pages are from Ordinary Level Physics, Abbott, 3rd edition 1977.
Les
It's not an apothecary's balance but a run-of-the-mill beam balance as used in school labs until the 1960s or so, when they were gradually replaced by the new-fangled top-pan balance and later by electronic balances. It is accurate to tens-of-milligrams, maybe milligrams if it's a good one.
The...
The potential show-stopper is how deep the rust has penetrated on the flat side of the blade. If it has caused significant pits it is impossible to achieve a truly sharp edge because the pits will always leave tiny notches. The only option then is to grind the flat side flat until the pits are...