- 9 September 2013 at 11:38 pm #18357Scott VParticipant
I got lost on the internet again, and found myself perusing an old 1887 book entitled Bench Work in Wood by W.F.M. Goss. In a section on m&t joints, he briefly described the process of drawboring, and then offers this disclaimer:
The drawbored tenon technique now seems de rigueur, but the stress that the pin must put on the tenon may give this claim credibility.
Off I go to another popular WW forum to dredge up some opinions, and I discover a 2008 thread where one of the participants displayed a draw-bored cutting board that looked very similar to Paul’s project. He stated that the design was from a WW magazine project that was based on a cutting board found in a medieval kitchen somewhere in the UK. Go figure. Small world?
The consensus on draw-boring seems to rely on the size of the pin, the thickness of the mortise, and the amount of offset used.
Is there a rule of thumb, Paul?
-Scott Los Angeles, California, USA9 September 2013 at 11:51 pm #18359kiyoshigawaParticipant
This is an awesome question, Scott. I was just designing some end tables that would use draw-bores instead of glue on the tenons, but if it’s a bad idea, maybe I’d better avoid it. I am curious what everyone else thinks on the matter.
-Tim Anderson, UT, USA10 September 2013 at 12:36 am #18360KenParticipant
Nothing wrong with drawbored mortice and tenons, it has been used for hundreds of years.
http://pfollansbee.wordpress.com/2009/01/25/drawbored-mortise-and-tenon/10 September 2013 at 1:48 am #18361Scott VParticipant
Thanks for the link, Ken. Follansbee quotes Moxon’s “about the thickness of a Shilling” to be the amount of offset. Now this yank just has to find a Schilling. 😉
I am mostly wondering if there is a rule of thumb for how many pegs, how thick the pegs, and how much offset. I assume this is what W.F.M. Gross meant by “great care and discretion”.
-Scott Los Angeles, California, USA10 September 2013 at 9:53 am #18545Paul SellersParticipant
Draw bores are very efficient methods for drawing up tenons. into the mortise. Generally they are unnecessary today because we have finely engineered long clamps as a direct result of the development of screw threads. The industry standard was of course nothing to do with the shilling but the eye of the man making that particular mortise and tenon joint at the end of his auger bit. Put the hole too near the shoulder line and you weaken the wood around the mortise, put it too far away and shrinkage will show along the shoulder line.I often see the pin in the middle of the stiles. Was this wrong? The Shakers did this a lot. I think mmuch depends on how well you know wood and in particular how well you know your woo; the wood you have had in stock. Lots to consider.
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