S-K 4270 First Generation Fine-Tooth Ratchet
In the early 1930s the Sherman-Klove Company had only recently formed its S-K Tools division, and was building a reputation as an independent tool producer after years of contract manufacturing for other companies. At that time S-K had one of their engineers, Theodor Rueb, working to develop a new type of ratchet mechanism. When the engineering was finished and the patent filed in late 1933, it's fair to say that the resulting product fully defined the modern fine-tooth ratchet. The patent was issued as #1,981,526 in 1934 and formed the basis of a very successful product line for S-K.
The figure below shows an early example of this new fine-tooth ratchet design, an S-K 1/2-drive model 4270, marked "Chrome Alloy" and with "Pat. No. 1981526". Although not marked with the S-K name, the ratchet can be readily identified as S-K production by the patent number, assigned to the Sherman-Klove Company. In addition, the distinctive forged handle is identical to a later S-K model, as can be seen by comparison with the Model 42470 Ratchet described in our article on S-K Sockets.
![[S-K Model 4270 1/2-Drive Ratchet]](Photos/tools/sk_12dr_4270_ratchet_forged_f_cropped_inset.jpg)
The ratchet is extremely well made, with the heavy forged handle hardened to the point that a file will barely touch it. The 50-tooth ratchet mechanism uses a pivoting pawl with three teeth on each side, providing a fine action without sacrificing strength. As the 1939 catalog puts it, "This is what the mechanic has waited years for. Has two to three times as many teeth as are found in ordinary ratchet wrenches."
The inset shows the reverse side with two "T" letters stamped in the handle; these appear to be factory markings, as some chrome appears in the bottom of one, and the handle is too hard to be stamped by casual methods. This probably indicates that the ratchet was contract production, possibly for Thorsen Tools, who were known to use a "TT" mark on their tools.
The origin of the handle design and model number for this ratchet can be pieced together with information from a 1939 S-K catalog. In the early 1930s S-K offered a model 4070R reversible ratchet, using a conventional shift-lever design and with a forged handle similar to this example. (The 1939 catalog shows this model as still available in certain tool sets.)
When the new fine-tooth ratchet mechanism was perfected, S-K adapted the forged handle design and updated the model number to create the model 4270 ratchet shown here. Then a few years later, S-K changed their model numbers to five-digit codes and redesigned the ratchets with a knurled handle, creating the familiar model 42470 ratchets that were made for many decades to follow. Although the catalogs show only the knurled-handle version of the model 42470, the forged handle tools were still being made, though perhaps only by special order.