What's the go on this clamp?

https://trademe.tmcdn.co.nz/photoserver/full/319007388.jpg

No clue here.

I hope somebody finds out.  I got one of these in an auction box lot last year.  Have no idea what it's for or what it's worth.

Mike

Weird piece , would like to know how and why also.

If you pinch those two tapered legs together,  does it let the screw move freely?

Very interesting, I have no idea what its for. I hope someone here knows.

Keeps all the letters from falling out onto the floor when you put them in the printing press...

Quote from: rusty on June 04, 2014, 09:12:31 PM
Keeps all the letters from falling out onto the floor when you put them in the printing press...

Sounds right.  I have an easier time thinking of the thing spreading than clamping.  I was thinking of those "cute" little bottle jack looking things used by machinists.

I thought of both those possible responses, but it looks too big to be a typeface locking clamp, and too roughly made to be a machinist's screw jack - I reckon the answer's still out there somewhere...

I guess if this one is an 8" lock(ing clamp), there may be other sizes out there as well..... bigger and/or smaller???

The tapered nut arrangement looks like some sort of quick release adjustment, to allow rapid insertion without having to fully wind out the screw - I think we need to look at something that needs to be 'locked' in place, e.g. holding some workpiece on a machine, or maybe locking up a machine (steam engine??) while it is being worked on....

Apart from these few 'gems of wisdom' (????) I've no idea.....

http://www.briarpress.org/23442

Rusty, you pull through again. Great research!

Well done indeed, a couple of sentences from the link stick out, as they seem to contradict each other a little...

Freewheel Out, Ratchet In, and locked with Pin Bar or Thumb Screw. Only ever used flat, and occasionally, and never intended for sustained and pressure use

Their one fault is that they will automatically release if tightened too much! You can be putting the final squeeze on them and POP! No damage to them other than they release the tension

Not to tweak the odd last, 1, 2, or 3 point on lock up, because if normal height quoins, can destroy even the BEST MONO-TRYPE strip material, what will 3 em (ish) high speed quoins DO.??



Copied the image link for ease of reference...

Looks they were available from 1 1/2" through to 5" (maybe higher, if the 8" is correct) and mainly used on flat bed or proofing presses - the illustration appear to be holding a litho stone in place, but the quality of the image is not good enough to be sure...

Question?? Are the tapered nut jaws spring loaded?? Can the lower ends be pinched together to allow rapid insertion, and is this why they may 'pop' out under pressure???

Thank-you Rusty. Once again my question has been asked at the right place.