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0 pointslogrot1y ago0 comments

> If the glue has failed, there are some serious craftsmanship issues regardless of the joint type.

No. You can't simply use whatever joint you want and expect the glue to deal with the (sometimes enormous) forces applied to it.

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WhatsTheBigIdea1y ago

Agree that you "can't expect the glue to deal with the forces"

A good craftsman would not choose a joint that would see such high stresses.

Additionally if the glue is chosen and applied properly, the wood that the glue adheres to should fail long before the glue.

That said, glue is not as simple as it may seem. There are many different types and proper surface prep and application makes a huge difference to ultimate strength.

For example, many people will mix 2 part epoxy until it "looks mixed" which for a clear epoxy happens pretty quickly. In truth, the resulting bond strength is far more closely related to the amount of mechanical energy that has been transferred into the mixture than the visual uniformity.

Lots of ways to go wrong with glue... but a good craftsman should be well aware of these.

rfrey1y ago

This goes against the conventional wisdom that a properly glued wood junction is stronger than the wood itself, and that under such forces it is the wood that will fail.

lmm1y ago

The wood would've failed at the same place if you'd carved a whole chair in that shape out of a solid piece of wood. The problem is that the design concentrates forces at the joint (or the "junction") in a way that no material can withstand.

btbuildem1y ago

It really does depend on the joint type. Do you expect a lap joint to hold together without any additional fasteners or glue?

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