Clamping Pressure For Wood Glue

Third it overcomes minor surface imperfections between mating surfaces.

Clamping pressure for wood glue. As the glued up piece goes through the normal expansion and contraction cycles in response to temperature and humidity changes the elevated forces you squeezed into the wood with excessive clamping pressure keeps trying to return the wood to its original shape. Dale zimmerman of franklin international maker of titebond woodworking glues recommends 100 to 150 pounds per square inch psi for clamping softwoods and 175 250 psi for hardwoods. When those forces cause a failure it might not involve the original glue joint. For softwoods pine poplar.

In addition to getting the two pieces of wood close enough together for proper gluing pressure also squeezes out the excess adhesive and pushes the glue into the microscopic nooks and crannies. During extensive research they undertook on gluing and clamping pressure the only manufacturer s reference the folks at lowell thomas tool found was on the titebond website. Too much glue can cause glue run out problems that will likely cause other issues at the time of finishing the project. In some cases where adhesive is only on one of the mating surfaces pressure also assists in transfer of the adhesive to the other face.

The fine woodworking article also gave rough estimates of the average pressure various clamps are capable of producing. And fourth clamping holds parts in position until the glue cures. Additionally consider how much the moisture in the wood will cause the wood of the joint to swell. Too little pressure will fail to achieve any of these benefits.