On Saturday, February 11, 2017 at 10:14:13 AM UTC-6, Leon wrote:

I guess some of us use our clamps more than others. ;~)

But Leon... think of the great OSHA/science information you got from a comment on clamps! I was surprised though, that the engine left the track the second post after yours...

I knew about the compression withing the clamp head and its grinding feel after use. I was told back in the mid 70s (when the whole shop had something like 10 Pony pipe clamps!)to put a drop or two of "3 in 1" just where the clamp screw rotates in the clamp face. it was explained to me that the heavy clamping pressure could/would gall the inside of the contact surfaces and make them have that grinding feeling when compressing. About every 4 or 5 glue ups we would hand the pipes on a boards and apply the oil. We used those clamps for everything. Remember a day with no Besseys, no cabinet clamps like we know them today. I still have some 50 year old Pony clamps and even have two ancient bar clamps from the 1920s. The Pony clamps are used on occasion, but the bar clamps are bent and are more of a curiosity.

Strangely, I hadn't thought of it, but your comment hit home. I rarely use clamps anymore. My squeeze clamps are in constant use for all manner of things, sometimes just an extra set of holding hands. But my Besseys, my old Irwins, my no name aluminum bar clamps, and my Stanley brand pipe clamps and Ponys haven't been touched in a really long time.

I do appreciate the comment on the wood Jorgensons. I have watched mine "relax" more than once, and gave all but one or two away since I thought they were defective! I thought the dirty threads would make them stick more, but if you think about it, the dirt probably acted more as a lubricant, keeping the friction quotient too low for them to work properly. That's a good tip!

Robert