I recently purchased a Union #3. The interesting part of this plane is it is a Union plane with the Mosher Patent lateral. Back on the BIRMINGHAM PLANES (“B” PLANES) page I mention that Birmingham Plane Manufacturing Company (Birmingham CT) operated from 1885 to 1900. In 1891 Birmingham Plane Manufacturing Company was reincorporated as Derby Plane Manufacturing Company, but it is believed all planes were still labeled as Birmingham. In 1900 Union bought Derby and continued making the bench planes. Some Union marked planes can be found with the Mosher patented lateral. According to Roger Smith’s Patented Transitional and Metallic Planes in America, they were made in sizes 3 – 8.
The B plane patent was given to George D. Mosher on October 22, 1889.
In 1900 Union Purchased Derby (Birmingham) Plane Manufacturing. 1900-1903 Union only manufactured the B plane. It was in 1904 that Union started making the planes with their patented lateral lever which is included in patent with the X series design. This was patented by John W. Carleton and George E Trask in no. 763,721.
If you look at the UNION PLANES AND WHAT I KNOW ABOUT THEM page the frog base looks similar except for the grooving. It’s hard not to wonder if there were some relationships prior to the buy out.
So here is a Union plane with the George D. Mosher patented lateral. (patent 413-300)