Some owners worked them so hard that they had to replace one or several parts.Some simply put the wrong bit in the wrong place, some customised their tools to suit their needs - the possibilities for change are endless.There are detailed type studies available, usually starting with type 1 for the first model then going up with every little or major change.
Time Testedtools Dating for Sargent #400 series Time Testedtools Dating for Sargent single number or Shaw patent series Union Planes and What I know about them (The best books are Antique & Collectible Stanley Tools Guide to Identity & Value and Patented Transitional and Metallic Planes in America) Time Tested Tools Dating for Stanley-Bailey’s Hyperkitten Rex Mills Stanley Trademark Stamps at Virginia Tool Works The Superior Works By Patrick Leach Stanley Plane Dating Flowchart at Wood Centeral Stanley Plane Features Timeline Mega Chart Bailey Identification at Virginia Tool Works Time Testedtools English Plane type study draft Virginia Tool Works A Stanley #140 Rabbet and block plane Study (oldtooluser.com) Record hand plane dating.
The information in this Web page is derived from a type study done by Roger Smith, in his book "Patented Transitional & Metallic Planes in America." Patrick Leach reformatted the type study and added comments based on his experience with Stanley planes.
I converted the type study to hypertext and added the plane dating flowchart and feature timeline.
I intend to eventually format the data into a more usable format, but for now I want to put it out for reference and feedback.
By cross-referencing the key features below, you should be able to narrow down the age of your plane to within a few years of manufacture.