Re: scarfs vs puzzle join

Posted by Alan Speakman on Jul 27, 2006

Hi George,

Wow! In your "uneducated opinion" you asked a great question! Some thoughts...

Obvioulsy, wood grain doesn't like being glued end grain to end grain. The tensile strength of end grain to end grain ain't so hot... That's why we like shear joints... Shear strength is off the scales... But now, enter the puzzle joint... It contains the advantages of large epoxy glue area (some of which is not end grain to end grain by the way) AND the shear strength of the epoxy-saturated "patch" AND the simple mechanical advantage of the puzzle joint itself.

If there is a weakness in the system, I'd say it's that the bending of a puzzle joint would put distinct pressures on certain surfaces of the "epoxy patch"... If that patch fails, water enters, rot happens, or even worse, things really go downhill fast...

Factor in the cost of production, the waste plywood, the bottom line for the consumer...

No doubt CLC is on top of this one... This should be interesting...

Alan

In Response to: scarfs vs puzzle joins by George on Jul 26, 2006

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