Not meaning to knock DowelMax, but one place that dowels do not seem to work well is to attach the seat rails to the back stiles on a chair. I do some restoration and every chair I get that's attached with dowels is loose or worse. I think the reason is that the grain of the dowel is perpendicular to the grain of the back stile. That means that part of the dowel is facing end grain which doesn't provide any strength. So there's just not enough face grain to face grain contact to provide the needed strength. And most of the chairs only have two dowels on that joint.
To my mind, that's one place where a regular mortise and tenon or a loose tenon (Domino) is called for.
Mike
Ancora imparo
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