Outside Dado Blades - Beware

[Steve]

I learned the hard way today that there's a right and a left outside blade for my Freud SD208 stacked dado set.

After happily cutting nice box joints for quite a while I pulled out my trusty dado blade today to make four desk drawers. I cut the first set carefully and dry fit - a bit looser then usual, must be the MDO plywood I'm using for the first time. Anyways, forged ahead and whipped out the rest of the drawers and dry fit - well, these went to the scrap pile.

Must be something wrong with my home-made box joint jig - nope. Maybe something got jammed into the dado stack - nope. Then noticed I didn't have the outside blades with the 'painted' sides on the outside as usual - yep, that was it. The cut is slightly wider with the blades reversed.

I don't know if all stacked dadoes are like this but mine sure is. Hope this note keeps someone from wasting some drawers like I did. Hope my next project has some smaller drawers so I can use that scrap.

Steve

P.S. The 1/2" MDO plywood I got at Menard's is pretty nice stuff - five plys, real stright, no voids that I've run into yet, and not too pricey either. Poor man's baltic birch, I suppose.

[Pounds on Wood]

Good advice. So far as I know, all stacked dado sets have specified outside faces.

Don't feel too bad though, I have put a chipper in backward before. Leaves a nice black streak in the groove.

snipped

[Tom Kohlman]

Thanks for the advice. The Delta 8" had no instructions whatsoever and I guess I never gave it any thought that there was any significance to the fact that one blade had writing on it and the other didn't. I have always put the latter on the arbor first since that is the order they come out of the box I built to store it in. Is that correct or should I reverse the two?

[B a r r y B u r k e J r .]

My Freud set, which I can't remember the model #, has "This Side Out" and rotational arrows printed on both blades.

Barry

[jev]

All stacked dado sets I'm familiar with have beveled tooth cuts on the outside blades. Mount the blades so the high point of the bevel is on the outside.