Cutting box joints on long boxes

With a size that big, my first thought would be forget the power tools and grab a few saws. If you want to go with power tools I would suggest using a dovetail jig with a straight bit.

Not knowing what tools you have available leaves this question wide open.
There are several commercial dovetail/box joint jigs out there you could use with a router. The best one probably being a Leigh (expensive). They would be the best and easiest.
With care and good supporting jig it could be done on a table saw or with a band saw and chisel. Careful cutting with a jig saw and some chisel clean up would work. With some imagination you could most likely come up with a home made jig to guide your router. Sort of an upside down table saw jig. Finally as CanadaJeff says, use a hand saw and clean up with a chisel.

-- Les B, Oregon

I would cut them by hand just like dovetails. If I was in a hurry, I might use power tools to help me along.

-- Debt is nothing more than the 21st Century's form of slavery.

Suppose I should clarify that. I’d cut the first side with power tools, then mark up the second pice for the fitting if I ws in a hurry. Sort of hard to do it by hand with power tools ;-))

-- Debt is nothing more than the 21st Century's form of slavery.

Make a clamp on finger jig and use a router… I would try the table saw but I don’t have 14 foot ceilings, (just kidding on the table saw). ; )

-- Never board, always knotty, lots of growth rings

Actually, that’s the main reason I asked, and left it open-ended. Even if I had a tall jig to hold the long pieces vertically, my ceiling height wouldn’t allow it.

-- Measure twice, then try to figure out which one was right.

They don’t have to be mounted vertically, do they? Just raise one end on a taller sawhorse that puts the end up at about 48” or so. Clamp on your jig and run your router hand held.

-- Until you spread your wings, you'll have no idea how far you can walk.

Trying to do it on the table saw, I meant.

-- Measure twice, then try to figure out which one was right.

Trying to do this by TS I think I’d try the following.
Make your llong sides 1 ft longer then machine all 4 sides to width.
Cut 6” off each end of the long sides then cut box joints on the TS using the normal dado/shop made jig setup as if you were making a 6” x Short side box.
Line up the 6” pieces onto the actual long sides and clamp them down.
Hog out the bulk of th waste with a bearing guided router bit, then switch to handsaws/chisels which can be guided by the 6” box joint cuts.

-- Use the fence Luke

Interesting approach. Must resist urge to make “outside the box” joke.

This would probably work pretty well, since at this point a router and a table saw are about all I have.

-- Measure twice, then try to figure out which one was right.

A Japanese fine cut saw, and a good sharp chisel. How thick is your stock?

-- Eagles may soar, but weasels don't get sucked into jet engines! Mike D.

1/2 or 3/4.

-- Measure twice, then try to figure out which one was right.