How does this C-Clamp work . What makes it get tight on the sliding bar?

[jdefrange]

The Michigan Clamp Company manufactured the Twistite C-clamp. The Jackson, Michigan company was registered in 1943 and cancelled in 1945. The clamps are sometimes found with military markings.
Machinery was primarily for die cutting and concentrated on bending and cutting steel rule. C-clamps and vises under the Twistite name were advertised from about 1942 till 1949.

A wiki dedicated to research into and preservation of artifacts related to the industrial revolution.
wrenchwiki.com

 

[slowtwitch73]

I assume it's a fast action clamp and you twist it just at the end to really hold... saves screwing all the way in or out. I think yours is assembled backwards.

Michigan Clamp Company - wrenchwiki

The Michigan Clamp Company manufactured the Twistite C-clamp in Jackson, Michigan.

wrenchwiki.com

 

[jdefrange]

yes but what makes it get tight when you turn it clockwise

 

[jdefrange]

I assume it's a fast action clamp and you twist it just at the end to really hold... saves screwing all the way in or out. I think yours is assembled backwards.

Michigan Clamp Company - wrenchwiki

The Michigan Clamp Company manufactured the Twistite C-clamp in Jackson, Michigan.

wrenchwiki.com

It works very good I just cant find a way to take it apart . Clockwise tightens and as you keep turning the threads you see clamp down

 

[larry_g]

one-way locking ball bearing clutches - Google Search

I'm guessing that it is some sort of a one way clutch that locks the shaft to the screw in two directions at once allowing the shaft to lock onto the screw. To take it apart look real close to how the Tee handle is fixed to the shaft. Remove the Tee handle and then unscrew the nut from the C-frame and tilt the whole thing out of the frame maybe?

lg
no neat sig line

 

[jdefrange]

Yes that was it, so simple. Are these rare.

 

[Ricky Joe]

Wilton made a clamp on a similar principle, where you slide to get close and then tighten.

 

[Mark Stansbury]

Twistite Quick-Acting Push-Pull Clamps, Vises by Richards' Industries, Inc. of Grand Rapids, MI, from Hardware Age, July 28, 1949.

 

[Mark Stansbury]

Ad from Tucson, AZ newspaper, Feb. 22, 1943, showing Twistites were used by Consolidated Aircraft for manufacturing the B-24.

 

[Mississippi333]

I have had one for years but it had been locked up in the roll pin/threaded area. I didnt want to clamp down hard and scar anything up. I happened to see it in a drawer about a year ago and started spraying it every now and then with penetrating fluid, all kinds. Well one day I picked it up to spray it and I was able to turn it lol. The little pin had a little rust and the insides as well. Its so close a fit, I'm guessing it doesnt take much rust to lock it up. Mine is the same build as OPs. But messing around with it, I keep thinking there should be a locking nut just below the handle in the threads that stick out on the top. Ive looked at flipping the threaded "nut" but it backs off to easy and wants to turn out after a couple actions. I always thought it had a locking nut but seeing OPs picture, maybe not.

 

[Mississippi333]

I was wrong on my above post. Like you guys mentioned above, twist right to disengage and adjust. As soon as the handle is turned to the left, the pin/pins (larger clamps have 2 pins) travel up a small ramp and lock the shaft onto the "nut", the threaded part. After its locked together, the threaded portion screws down to do the actual tightening. I had never been able to use mine due to condition i mentioned above, but after I finally made time to tinker with it and actually clamp something, it seemed so obvious. Those threads always just looked out of place sticking out the top lol. Well, I learn something new today. Its been a good day. Until a later time hopefully, good day to all.

 

[Mississippi333]