Drill No. 2A Transitional Construction Elements

This variation in ball numbers was dictated by different diameter of the spindle and spindle seat used in the drills over the years.  The spindle diameter on No. 2-1938 is 0.21875".  The No. 2A - Transitional returned to spindle diameter of 0.25", used on models from 1895 up to 1920.  With larger diameter of the spindle the ball bearing in No.2A Transitional was also changed to one ball without races and then carried forward to No. 2A - Zamak and later models.

Spindle and Ball Bearing on No. 2 - 1938

Spindle and Ball Bearing on No. 2A - Transitional

The change in the spindle diameter and thread size required change in a chuck as well.  The chuck used on 1938 No. 2 drill was designed and patented by Henry A. Ryther, an employee of Millers Falls Co.

The patent receive No. 1,470,197 on October 9, 1923.
It was one of the best, if not the best, chuck designs of the era.

The same chuck was used on No. 2A Transitional drill and continued on the later, 1957 version.  Obviously, the opening was changed to the 0.25 inch and the thread to 24 TPI. 

On the left - Chuck from No. 2 - 1938 drill.  On the right - chuck from
the No. 2A Transitional drill.

Chuck from the No. 2A Transitional drill.

Another significant change occurred in the main handle mounting parts.  However, this change was initiated in later version of 1938 model, most likely in early 1950s. The original 1938 No. 2 hand drill continued with concept used previously on drills from models released between 1903 and 1935.  These were the drills that employed a friction roller at the top of the single pinion and main gear. 

All these drills were designed with a threaded stem at the end of the frame.  It served as a mounting screw for main handle.  Although the opening in main handle was not threaded, it was screwed on using moderate force and pinned to the stem through the handle's ferrule.

With 1938 model the frame was redesigned to accommodate second pinion.  The system had to be created to provide a way to secure the pinion and main handle in place of previous threaded bolt.