Wedged half dovetail and pegs

[canopy]

Consider a 6x8 tie beam with a typical wedged half dovetail with through mortise. There seems to be two schools of thought. Jack Sobon's book says no pegs are needed, just the wedge. Yet old school and modern designers alike seem to favor putting two pegs in the joint in addition to the wedge. It would seem better to omit the pegs if they are not needed since it keeps more wood in the posts. I would be interested in understanding any underlying reasoning for going one way or the other.

[Jim_Rogers]

I would guess that it all depends on access.
Will you have access to the wedges to pound them in later on after your frame has dried up a bit?
If you do then wedges would be the way to go.

If you don't have access later on, then draw boring with pegs and wedges maybe the solution.

Jim Rogers

[Jay C. White Cloud]

Morn'n Paul,

As you already know from our conversation, the style we work in is almost all  Asian, from the part of the world you are in. ;)  Most joinery is lap (a gravity joint) or wedged (a friction-compression-or drawing joint form.)  The wedging is on top, bottom or in a drawing capacity.  Some tenons are pinned with square pins, (or round if you  choose, or simpler for you). but not if they have a wedge, the redundancy is not necessary. 

Now if you are going to choose a Anglo/European frame design, and want to use a "compression wedge dovetail," I can share that we have put 4 of them in European folk style frames that we did last year, and we have even more planned this year for similar frames.  None will be pinned/pegged.  I can also share, that in the (maybe 20 plus) vintage-original versions of the joint we came across last year in old frames from 1690 to 1780 and a few from the early 1800's, none of them had pegs either.  So, in vintage frames, in my experience, seldom are they pinned/pegged.

Regards,

jay

P.S.
Jim's conclusions are sound, I would just add this/or adjust his comment as follows.  The wedge must be fitted in such a manner that it preforms it's function, other wise, use a "draw bored" tenon.  I will add, that the joints that we see, even if they have loosely fitting wedges, after the centuries, performed excellently.  Even after loosening, to take the bent apart, the bent frame was still very solid, and this is a marvolous joint to use.  We love gravity and wedge joinery, it is one of our trademarks. ;D