Timber Framing 2 - Mortise and Tenon

The mortise and tenon is the king of joints in timber framing.  It has a myriad of variations to be used in the wide range of joinery situations that come up in a timber frame.  Whether it is augmented by simple pegging, draw boring, or wedges it is used everywhere.  So find below some of the making involved in some mortise and tenon joinery. 

Fist off, the tenon.  

Prior to the video starting a circular saw was used to kerf almost down to the tenon cheeks.  The bulk is cleaned off with a chisel and then pared down with a slick.  Then back to the chisel to define the base of the cheek (end of video) and then to a jack plane to finish off.  The video is sped up 3x, it is a lot funnier to watch that way.  

Hand tools are still the go to for final cleanup and precision. 

Flip the board and repeat. 

The mortise video only shows the roughing out by using a chain mortising machine.  It's a pretty cool machine, essentially a small chainsaw guided on rails.  This mortise is 2 inches wide, 8 inches tall and 5 inches deep.  Six and a half minutes is a pretty quick rough out.  It is followed by paring with a chisel to clean up the side walls, bottom and corners.  This video is also sped up 3x. 

This particular mortise is on a rafter which will receive principal post and hammer post tenons.  These will join at an angle and thus require a sloped shoulder to get full width joint support.  The slope was primarily cut with a pair of guided circular saws and finished off with a hand saw.