sash clamps, new v old?

[wcndave]

If it's cramping up a mortice and tenon then I'd agree, you need just enough pressure to bring the shoulders home, and if the joint's been cut right then that's not much at all. Anything more just risks distortion.

But if it's jointing up an Oak table top then it's a different story, for absolute maximum strength on Titebond III for example the recommended pressure is 175-250psi for hardwoods. So in a hobbyist or small commercial workshop you can't over-cramp, as for all practical purposes you can't physically get enough cramps on the workpiece to exceed the recommended pressure.

OK then, surprised you need that much, but hey, live and learn!

 

[custard]

OK then, surprised you need that much, but hey, live and learn!

I was surprised too, but here's the manufacturer's data sheet,

http://www.titebond.com/product.aspx?id ... 3970f736af

Elsewhere I've read that the absolute minimum pressure required for even moderate bonding strength is about 12 or 13 PSI, which was sobering because it implied that for successful vacuum bag veneering or laminating I have to get every single detail dead on accurate, because there's virtually no room for error.

 

[AJB Temple]

wcnDave. Sure helpful. Thank you. I have been looking at Bessey over here in Germany lately. Not bitten the bullet yet as I can get them any time. The only reason for specifying sash cramps is that T bar sash cramps was what I have always been used to!