Taiwanese Mill Drills badged as Naerok, Warco, Nu-Tools, Sealey, Whitecote, Excel, Draper and Ajax, etc. . Although not machine-specific in content, it covers the the "Minor", "Major" and similar variants and, being a double-edition manual, it should help with most versions.
Draper
Manuals and Catalogues
Warco Taiwanese Mill Drills also badged as Warco, Nu-Tools, Sealey, Whitecote, Excel, Draper and Ajax, etc. . Covers the Types FR-30, RDM-400/500M/500MF, "Minor", "Major" and similar variants. A double-edition manual that will help with all versions. As with most machine-tool manuals, it's a good idea to back up the manual with a "how-to-do" book - and in this case I can strongly recommend the inexpensive one below, "Vertical Milling in the Home Workshop"