Age of 2 Vise Grips?

[dimwittedmoose51]

Below are two pr. of vise grips.  One pair is so rusty, there's no logo on=r anything to be salvaged and the retention spring broke, so unless I can replace that, these may just be for "show".  The other pr. had ju8st some surface rust on them and cleaned up very nicely.  They say "vise grip  dewitt neb.  pat. Apr 8 24"     

I realize that patent dates and manufacture dates are different, but since both these have no lever release, they are pre-1957, but some folks like me would like to narrow it down a decade or two closer.

TIA


DM&FS

[kxxr]

on the one that has the hex bolt in the handle, is there a hole in the side not showing?
The exaggerated 'trigger' shape in your first picture release handle was gone in the one pictured in a 1949 advertisement I saw. Your second picture has the less curved handle, as it appears in the 1949 ad.
The ad and some more history can be found here:http://www.livinghistoryfarm.org/farminginthe40s/machines_12.html
I can't offer proof, but I think the first one pictured, especially if the bolt is original, is a very early design, possibly 20s or 30s. I'm no authority of course, these are just my guesses.

[kxxr]

Then again, here's a 1924 patent picture, also with a straighter handle

7 inch. Note pivoting jaw in slot in back.
The patent site also says: "A major reworking of Petersen's Oct. 4, 1921 Pat. (no. 1,392,443), the "2nd Model" vise-grip has the adjusting bolt and locking lever. Early production at DeWitt, Nebraska assembled tools from forgings produced at Buffalo, NY. Some of the oldest surviving examples are stamped "S.P.W.Co." reflecting the short-lived Sire-Petersen business partnership. The frame and lever handle forgings were eventually replaced by stamped pieces fabricated at DeWitt. A few of the earliest stamped steel body Vise-Grip® pliers using the 1924 design (see 3rd picture) have survived. Petersen's May 21, 1940 patent (no. 2,201,918) and April 14, 1942 patent (no. 2,280,005) show the parts made of stampings."

[kxxr]

here's the 1938 application drawing. Patent granted in 1940.


None of this really helps you date your tools, but I thought you might find it interesting anyway. This one looks a lot like your 2nd pictured one, but:
"The patent shows "the state of evolution" of the Vise-Grip® in the mid-1930s. The body and handle are formed of stampings rather than the castings shown in the 1924 patent (no. 1,489,458 ). Petersen Mfg. had made the transition in their production some time in the interval between 1924 and 1938.
The patent includes a slide in the swinging handle that would prevent the "over-center" link from locking.
No examples referring to this patent are known. The usable features were incorporated into Petersen's April 14, 1942 patent (no. 2,280,005)."

[kxxr]

Here's the 1942 drawing:

"This patent is the "kick-off" point for all post WWII Vise-Grip® pliers. It incorporates the change from forgings to stampings, and other changes in the tool subsequent to the April 8, 1924 patent (no. 1,489,458). The focus of this patent is the spring, slotted handle, and base of the "stub lever." The specifications also note Petersen's May 21, 1940 patent (no. 2,201,918), which includes features never incorporated into the tools. Some early production is marked with the 1924 patent date although the tools clearly match this patent.
The addition of Harold T. Jones' lock-release lever in the mid 1950s (pat. no. 2,514,130) was the last major change."

[dimwittedmoose51]

Thanks XR, that narrows it down a bit./  The top one is definitely stamped, but your explanation of the new  hex bolt style using the old patent info hones in on the date.

DM&FS