Q. How tight for dovetails: this woodworker and his son just cut a bunch of dovetails successfully, but they are having an argument about how tight the dovetails should fit, especially as the cold weather sets in and the humidity goes down.

(Lee Grindinger) The dovetails should be properly snug. Both pieces will move in the same manner, so the pins and tails will not be working against each other. As the tail increases in width the space between the pins does, too, so there is no conflict. The only time a problem could arise is if the direction of grain in the pieces is different, and if this is the case, a dovetail is not a good choice of joints.

(Simon Watts) Dovetails should be a snug fit and, because the grain direction is the same in both parts, the fit is affected only minimally by changes in humidity.