Rust and paint removal, machine parts and screws, I use a bench grinder (outside) with an 8" soft wire wheel. Takes a little practice but removes rust and paint quickly. Leaves surface ready for degreasing and painting or oil blacking. I treat bare metal and oil blacked parts with beeswax furniture polish. Machine body and large parts, angle grinder with wire wheels, flap wheels, scrapers, sandpaper. Bearing and sliding surfaces (just to clean and derust prior to remedial work), angle grinder with soft wire wheels, scrapers, wet or dry abrasive. Wire wheels for both bench and angle grinders come in at least 3 grades, soft, medium, hard. Exercise judgement, you want to remove rust and old finish not metal. Chemical, strippers that work no longer exist in this part of the world. Cleaning off 90 years worth of rust, flaking paint and congealed nastiness is a boring, filthy job, I like to get it over with as quickly as possible so I can get to the interesting stuff. I wear PPE for eyes, lungs, hands and body when using wire wheels. The wires break off the wheels in use and travel fast enough to penetrate clothing and flesh.
I usually apply paint by brush and roller. Tractor paint is good!
Cutters with 1.25" center holes. I have a few of these together with a sleeve, about 1.5" dia, a 1.25" shoulder at each end and a 1" bore. The sleeve can be fitted to a 1" arbor and supports 2 cutters a fixed distance apart so that 2 (or more) surfaces of the work piece may be machined simultaneously (Gang milling). The sleeve is easily made and allows the use of cutters with a larger center hole than the arbor. Light gang milling (light because this is/was usually done on large and heavy machines with bigger arbors) can also be done with spacers separating 1" cutters on the 1" arbor, the method may be useful on smaller machines but with lighter feeds. Precision spacers and micrometer adjustable spacers are available for this purpose.