A butt joint is one in which one item touches another with no mechanical means of staying together. The concept of a joint join depends on the use of the adhesive or on the situation. In woodwork pieces of wood can butt up to another side by side without glue ~ for example when laying boards down for a wooden flooring. A better job involves jointing floorboards together with tongues and grooves ~ that method cuts down on draughts ~ and allows for secret nailing. It also allows for expansion of the wood ~ glueing would interfere with that and cause problems. I suspect that such 'T&G' does not qualify as a butt joint.
At times it may appear that the end of one piece of wood is butted up against another at right angles. If glue alone is holding such a joint it is suspect craftsmanship ~ and it will soon fail. Appearance can be deceptive since a concealed joint ~ such as a mortice and tenon ~ is commonplace ~ and it looks very much like a butt joint.
This is a link to notes on raw edges [112119]
