yes, the dovetail shrinks more at the wide side than the narrow side. So the wedges should be initially tight on the wide side and a bit loose on the narrow side. I'm thinking of wedging both sides of the dovetails, so the change in geometry will be split in half.... It's a lot of to-do to deal with the dovetail and next time I'll be checking out the cog. The English Tie Joint frame is quite rare in my area.
This building is 12'x15' and we are using a kingpost with principal rafters and ridge so there will not be too much tension.
I plan to leave a gap between the teasle tenon shoulder and the tie beam seat.(and milton,your post tells me there should be a similar gap on the upper shoulders of the post/tiebeam braces) Also a gap on the plate side of the teasle tenon mortice.
The question that remains for me is pegs.
I don't mind leaving out the pegs in the teazle tenons(we have common rafters running from ridge to plate that will tie down the tiebeams), but would like to peg the post/tiebeam brace....
Will, how do you deal with plate shrinkage in the post/tiebeam brace?
and by the way Will, have you not picked up the fine art of standing on the mortiser base?(grin... don't tell ontario workplace comp I said that....)
