American Woodworker article on Adjustable Box Joint Jig

Just now getting back to my pile of unread magazines. I’m looking at the January 2008 American Woodworker page 36. It details making an adjustable box joint jig. I’m curious if anyone has thought about making this? Also, I have some questions for those who are more mechanical than I am.

I think the idea of an adjustable fence that is shown has great merit. My concern with the design is the removable inserts. It seems to me that if the opening for the insert and the insert are both 2.75” the fit would be super tight – almost to the point of not being able to get it in and out thus defeating the purpose of having removable inserts.

Saying that both parts are the same – you would need to tap the insert into the opening. Presumably you would also have to take the face of the insert (part D) off the mounting plate to tap the insert out of position. I would think if you did this enough times that the insert would eventually loosen to the point of making your cuts off by a little bit each time.

There is a dowel pin that positions the removable inserts – wouldn’t this act as a pivot point so that if the insert was loose it could move in or out when you change the position of your workpiece? (I understand it would not move back much because of the backer board.) I think it would only move minimally, but would that be enough to throw your joint off?

I’m on my lunch hour so I’ve not completed ingested this article, but had these questions and wanted to get them out there for my fellow LJ’s to educate me.

Thanks a bunch.

-- Betsy - GO BUCKS!