When I was there, Sentinel, as sub contract, were making Huddersfield planers, using a larger one by the same manufacturer, to machine the bed.
The operator used to ride to and fro, on the table, while sitting on a chair. When he rose to sweep the swarf with a broom, he ducked as the table passed beneath the gantry!
The gears for the bevel boxes were lapped together by filling the box and with grinding paste and oil and running for several hours. After a thorough washout and fitting new bearings, the bevel boxes were finally assembled.
This was in the shop where the locos were erected.
Larger circular components, such as flywheels and loco wheels, were machined in the main machine shops on vertical lathes, know colloquially as "merry go rounds, with chucks about 4 feet in diameter.
Can't remember the maker, Kendall and Gent? Someone will remind me.
Further up the road, on Harlescott Lane a company was producing huge boring mills. The machine started in a hole in the ground large enough to take a 3 bed house, and when complete, the column was about the same height above ground.
The slideways were coated with Formica, since with oil lubrication, the coefficient of friction was far less than cast iron to cast iron.
Howard