Reply To: End grain glue joints are always stronger than side grain joints !!!!

Absolute novice’s opinion.

The tests proved that the glue and materials break at the weakest point. Something that we all new.

End grain to end grain breaks at the glue point because that is weakest point. So if you glue side grain to end grain and the other end grain (20 mm long) to another side grain and perform the test the side grain will break before either glue joints and the end grain piece will never break.

This means in certain joints we could take advantage of this as Rob Cossman proved with his rebate butt joint (??).

So never glue end grains together to extend the length of a board is still valid as the glue joint is much weaker than the wood in that application as we designed that pieces dimension for lateral/tensile/load carrying strength which is much higher than lignin and glue.

However when gluing joints together and saying you don’t need to put glue on the end grains because end grain gluing is weak and not worth doing should perhaps be reconsidered and glue them anyway as it will improve the overall minimum glue strength (not joint mechanical strength) and might just close the joint lines better due to swelling of the wood.

Don’t you just love wood working!!