Post 15 in a series on the design and construction of a dining table which takes its cues from a unique Ming period side table.
This time around I’m working on the ‘ribs’ which attach to the ‘spine’ or central rail of the table. In the past few posts I have been cutting out that central rail, and concluded the process by mortising for the battens, or ‘ribs’.
The connection through the central rail will be accomplished by a variant of an open mortise and tenon called sao tsugi. Tsugi means ‘connection’ and sao means ‘rod’ or ‘pole’. Typically this connection is fastened using a pair of opposed and angled wedging pins, or shachi sen. I’ve detailed this joint extensively, including many variant forms, in the 3rd volume of my Art of Japanese Carpentry Drawing essay series – please excuse the shameless plug- and here is a picture from that volume of a typical sao tsugi:
In this case, I want the table structure to be more readily demountable, so I have decided to forgo the shachi sen and instead use a komi sen, or peg. That’s right, I’m violating one of the guidelines for the construction of this table, in which I sought to eliminate or reduce greatly the use of glue and pegs. In those cases were I am given a choice though between gluing or pegging, I will opt for the peg. In the original table, lacquer was used as an adhesive in place of any pegging for the joins between the battens and table rails, so I am choosing instead to use pegs along with some Japanese joinery techniques. I feel it is a better solution. At least all of the pegs I will use – and there will be a dozen in total – are not in view unless one lays underneath the table and looks up. So, a compromise is necessary, but a happy one.
After laying out the joints, I used the hollow chisel mortiser to process the peg mortises and rough out the rod mortises:
Next step was to rebate the sides of the battens to form the stub tenons:
I also moved along today with the main frame rails, the undersides of which I relieved in much the same manner as I had for the central rail:
The short side rails receive a similar relief treatment on their lower edge:
Thanks for coming by today. –> on to post 16