Timber Framers Guild Forums General General Forum Questions correct way to offset peg holes on open m&t rafter couple peak

I am reasonably conversant with the concept of using offset holes to drawbore when making m&t joints-except that is when doing an open m&t on a rafter couple peak, I am not sure in which direction to offset; at what angle or direction from the shoulders?
Also how would you peg a simple half lap rafter couple peak together? Doesnt seem possible to offset, do you just squeeze them up with a strap come a long and "pin" them with a wooden peg?

Could anyone give me some advice on this please?
Many thanks, Jonathan

The infamous double draw…

Sometimes I think most of the resistance to the use of drawbore, has much if not mostly to do with the requirement it holds for counterintuitive thought,

And how that might introduce some otherwise avoidable and additional possibility of error,

However, if it is always kept in mind that all movement in drawbore is in the counterintuitive direction,

Double draw is no trickier at all,

And like unidirectional draw, it is a big part of the green woodworking recipe that sees joints shrink up tight, and not apart.

Besides, you have those prickers on your side of the pond, easier still !

Will,
Way to go, the more I see your humor in print the better I like it.
But you still made the thought provoking thought.
Yea !!!

Hi Will thanks for your reply (Infamous double draw-are you john waynes sidekick? ) Personally I love drawbore pinning (I've always used it a lot in regular joinery but I am new to framing) and have never had trouble with it except at first when I tended to ofset too much and sheared out the tongues. :rolleyes:
Seriously though by counterintuitive direction is that what you mean by moving your offset towards the shoulder of the tenon? If you want to pull in a certain direction you offset towards the shoulder in that direction. So on the rafter joint you ofset slightly toward the inner corner to get a tight pull in two directions??
Cheers, Jonathan

Ps
Will, I forgot to ask, what is a "pricker"
Seems like an "old limey" should know??
Thanks, Jonathan

Directly counter to the direction you mean the joint to shrink,

Often strait towards the shoulder, far more often double draw is in order…

In the case you cite, a bridle joint / tongue and fork, both towards the shoulder and away from the crotch of the bridle. The intent being to both see the shoulder pull up tight , and stay tight as shrinkage develops, but also see the tenon stay tight to the bottom of the bridle as time brings shrinkage.

For the very same reason, in any type member tenoned into a post, both to the shoulder and up, pulling the joint down as it seasons, so the tenon is not allowed to shrink up and away from the bottom of the mortise where it needs bear and instead, someday start riding the peg.

In a brace, to the shoulder and away from the nose, completely counter …

These counter moves need only be subtle, 1/8 – 3/16ths max. The point of draw should not be focused on pulling the frame together at raising but on shrinkage. ( a well cut joint should find its way home to within the offset of the draw, if you need more, reach for some mechanical advantage or a chisel, relish is there to hold the frame together over time, not to be spent on and make up for an overtight joint or a lack of proper rigging )

I’ve had the great fortune to go timber tripping to your side twice, most recently to the Clumps event. “Prickers” seem almost universal, a machinist made tool, turned to a few under so you needn’t fight it in and out of the bore. Typically the handle end is knurled and also has a flat or some easily felt side which is always turned towards the shoulder (+ the secondary draw) and is opposite an offset nib which marks the tenon for drawbore at fitup

Oops, color me embarrassed,

I just reread your original post, and realize I somehow misread what joint it was you were talking about, and thereby missed the jist.

To answer your real question - No, as I see it there is no way to peg off and effect draw in a halving joint…

For this reason I have long chosen to forgo a pin at this location and instead use a variation with undersquinted shoulders, recently nicknamed the “handshake joint”. The idea being, to allow the joint to shrink together and into itself as it seasons. If there is some distance from the ridge to a butt purlin or a purlin plate, and there is a safety issue at raising or enclosure I will apply some kind of “gangnails” type metal fastener to avoid lateral dislodgement until enclosure is applied.

If a peg is not needed for tension, and might lead to a joint shrinking apart and not together I see no reason for one at all. I’d rather know the shoulder is bearing the opposite rafter, than worry that the pin is forcing only that material above the hole to do more than it’s share and in effect potentially split one or both halves. I see this as an issue in all high shrinking species

Let gravity keep you and the frame looking good.

Hello Will,
Thankyou again for your helpful and instructive comments
No need to be embarassed you did understand correctly at first what I was asking about. On rereading my post again, I dont think I wrote it down as well as I could have done. I had in mind the ilustration (fig 14)on page 38 of Mr Sobons historic American timber joinery; I was asking about pinning the first and second types. (I was asking two questions really!)
Until you mentioned it I never thought about the shrinkage factor and offsetting compensating for it. I'd been taught in regular (not framing) joinery that drawbore pegging was to pull joints tight, period.
Is there a diagram anywhere of a handshake joint Is it a new name for an old joint?
Again thanks for your help Will, Cheers Jonathan