A butt joint is the simplest joint to cut and to assemble. The wood can be joined at the ends, edges, faces or a combination of the three. A 90 degree butt joint is sufficient to hold light loads and will maintain its shape. Glue, along with nails or screws hold the butt joint in place. A butt joint is flat and smooth. No grooves or tails are used to connect the joint together.
It is best to use a butt joint on woodworking projects that will not bear a great amount of weight or will be twisted or moved frequently. The modern wood glue used to help bond the butt joint together is very strong. The glue holds the wood fibers together. A properly built butt joint with glue will break the wood gibers surrounding the joint and not the joint itself.
Butt joints used in drawers or doors should be connected with screws, nails or biscuits to help hold the item together. They add strength to the joint to help support the weight and twisting.
Make wide panels by but jointing several pieces of lumber together. This is called edge gluing. These panels are used for tabletops, workbenches and butcher-block surfaces. This type of butt joint is very strong due to the fact the wood is glued with the grain. This type of gluing is called long-grain gluing. Long-grain gluing takes advantage of a large surface area with many wood pores. The wood pores run parallel with the grain. This allows the glued butt joint to expand and contract evenly with the humidity and temperature. The parallel wood pores soak in enough glue to prevent the wood fibers from breaking away when excessive weight is placed on the surface or the wood panel is twisted.
The insertion of biscuits into a butt joint helps in alignment within a long joint. Use a biscuit jointer to cut the biscuit slots centered in the thickness of the board.
A butt joint is a good solution in making thick wood blocks. An example is creating thick blanks for turning or cutting table legs or columns. This type of butt joint glues the faces of the wood together. It is very strong due to the amount of wood pores saturated with adhesive.
Prior to using a face-to-face-butt joint it is important to run the wood through a jointer or planer to ensure the surface is flat. Wipe off any excess saw dust prior to gluing the surfaces together.
Butt joints have been used throughout history to build many items. The simplicity of the joint affords novice woodworkers with a solid joint to construct projects. Minimal tools are needed. As woodworking tools are purchased, other types of joints may be used to construct woodworking projects.
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