These are a cheap make that you find on garage forecourts and on market stalls. I saw these small clamps and thought they were worth testing at the very low price of £1.40 each.
Copper plated steel screw, bar and foot.
Heavily painted steel casting for the main body, no sharps edges and the cross-section is very substantial for the size of clamp.
At the maximum throat I measured 21/16“
I just wound the clamp closed and then applied as much force by hand as I could and it was fine. It unwound without any major issues. I repeated this a few times and you can just start to see some witness marks on the copper thread.
The foot rotates happily on the end of the steel screw, even under pressure.
The thread engagement feels quite shallow and there is movement in the thread side to side.
Price: approx £1.40 each.
For the price this really is very good and I′m sure will be in my workshop for the next few years happily doing the job it was designed to do.
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