Re: restoring old saws
I use citric acid to chemically remove rust, though you can buy Evaporust that does the same thing. Citric acid is aval in powdered form where wine making supplies are sold.
Do a google search for articles by Bob Smalser as he has publish a few good ones on saw repair. Some are available here.
Daryl Weir has put together some great info here and he is an accomplished saw guru. His site is here.
The cleanup is easy but it is the sharpening that takes a lot of practice. Good luck with your restoration.
Working in New Brunswick but weekends on Prince Edward Island