Hargrave brand of Cincinnati Tool Co are old school clamps and if you ever run across some get them.
The Cincinnati Tool Company was founded in 1877. In 1925, it changed its name to the Hargrave Company, which continued until 1955.
The information below was provided through the kindness of John McCutcheon, of Grand Rapids, Michigan
I got them at an auction with e biding i needed some 8 footer and got them for $20 a peace. these clamps are the easy to ajuist and stay put and must have a 6" thread travel on the business end. plus the I beam bar is very ridged..
if I ever see anymore i am grabbing them as they are the best clamps i have use where you need pressure . I find that if there is glue all over them they still work well not like the F clamps that must be kept clean. you don't see them F clamps in the rotating bar clamp set ups do ya, the F clamps are for light pressure gluing and for the most part that all you need but when you need pressure for curves or large glue ups you need pipes or bar clamps. though this are not a light to cling around they last for ever,
I just did up a big glue up of 8 40" x 84" doors with bar clamps and you can,t bet them for price per foot.
with some simile t supports they work well enough.
have a look
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