Dado groove using a Dremel?

[David Tolsky]

I have a 12" x 9" shallow box that has already been glued up with a bottom floor. I need to cut dado grooves on the inside front and back 12" boards. Naturally this would not be as big a problem if the boards haven't been glued up yet-table saw dado blades and done. But the box has been assembled and now I have to correct a mistake. The dados need to be about 1/8" wide. Thought of a tedious way: hand saw both edges of the dado and chisel out the grooves...don't think I want to do that. So my question is, can I get a straight bit for the Dremel, put it into something that will set the correct bit depth, and go to town guiding it somehow in a straight line? A Dremel is about the only tool I'd be able to fit into the box to cut the grooves.

[Randy Viellenave]

Dremel makes a “multi-purpose” attachment (available at a large orange retailer) as well as various bits (other brands of bits too). It is intended to be a roto-zip tool, but with the right bit it can have other “purpose”.
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This will not get something
perfect, but I think it would get a dado just fine.

[Michelle Rich]

I believe Lee Valley makes a bit JUST FOR thIS! check them out

[Andrew Pitonyak]

Slot cutting blade with a router would be how I would start.

[David Tolsky]

Can't get a bulky router in a small box but intrigued by the Dremel attachment. Thanks everyone

[Charles Lent]

If the dado will be near the top edge of the box you might want to look into getting one of these bits.

http://www.leevalley.com/US/wood/page.aspx?cat=1,46168,46176&p=47818

Set it up in your router table, adjust the height for the distance into the box that you want the dado, flip the box upside down over the bit, and run it on all of the sides that you want the dado. If you need square corners, you will need to chisel them out.

Now, my question. What is this dado slot for? If it's for the box top, how are you going to get it in there?

Charley

[Bill Conerly]

I had a similar problem; made drawers but forgot the dados for dividers. Solve the problem by glueing in small slats to hold the divider. Not sure if that's why you need the dados, but something to consider if that's the issue.

[Tom Giacomo]

I would mark out the dadoes with a sharp utility knife then remove the wood with a sharp 1/8" chisel, remarking the dado as you go. This would give you a nice finished looking dado a little tedious but that is the price you pay when you make a mistake. Don't ask me how I know that.