Starving the Joint of Glue

Years ago, when I first started woodworking, I was often advised that you should not make a joint too tight. A too tight joint would 'starve' for glue. It seemed reasonable that a joint that was too tight would force the glue out leaving an insufficient amount to form a good bond. Plus, it had a good sounding catch phrase, "Don''t starve the joint."

I went years believing this. The problem was that over time experience started to speak against it. I just never found it to be true.

As often happens, just when I was really starting to question this long held belief I stumbled across an article that addressed this very issue. I was in line at my local hardware store flipping the pages of a woodworking magazine, as I often do at the hardware store. It happened to be a copy of "Fine Woodworking Magazine". The article was primarily about testing different glues, but in the process they tested joint fit as well. Their conclusion: starving the joint of glue was a myth. The over tight joints were no weaker than the good fit. Of course, in their test they had all the tight joints the same; milled to scientific perfection. They were not "crazy tight".

I decided to do a more unscientific and much more satisfying test myself. I made a series of joints from snug to insanely tight. I'm talking the kind of joint that can only be called bad workmanship. Several of them broke merely because they didn't actually fit together. None the less I made up a sufficient sample to satisfy myself.

With some creative shop work I rigged up a tester and went to it. Broken wood was flying everywhere! It was fun. It also proved to support the findings in Fine Woodworking Article. Over tight joints were not weaker than snug ones. In fact, they were often stronger. Of course, the over tight joints had a host of other problems, most notably the wood split from the excess pressure of the over sized tenon.

My conclusion: starving a joint of glue is a myth!