SawStop Dado - One Step Forward, Two Steps Back

[Patrick Varley]

I use the Freud Box Dado set on my Sawstop. basically it's two blades that can either cut 1/4" or 3/8". If I need a wider dado, I just repeat the cuts and creep up on the width of the dado needed.

I did trigger the original Dado brake, that I bought new with the saw, circa 2014. The replacement brake was an upgraded version. No issues with that over the past 2 to 3 years.

Technically the Freud box joint set is not "approved" for SawStop as it has (at least when I had it), the anti-kiclback feature. It will still work, but supposedly may not stop as fast as it should.

While I will use a dado stack occasionally, most of the time I use a Ridge 10" 1/8" box joint blade and take multiple passes as you said. Saves having to change our the cartridge. I usually only go the dado set if I have to make many (wide) dados.

I thought hard about going with a WoodPecker rip stop since it has a dado feature that I think would have made this even easier. Went with a Wixey DRO instead, which still helps with the dados, but is more useful to me in general.

[Stephen Roth]

One note on using a full chipper dado blade on the saw stop....

I was using the SawStop (Industrial Model) with a Systematic Dado blade. (8" with all cutters installed.) The aluminum miter gauge hit the blade and WHAM!, the trigger activated. I have had the trigger activate before when I forgot that there was metal involved (such as cutting aluminum foil coated foam insulation), but this activation seemed much more "kinetic." In fact, the brake got shredded and sheared off teeth from the dado blade. Not just the carbide -- the actual steel that supports the teeth was torn.

So I figured I would check the alignment of the blade to the miter gauge, and found that it was out of alignment by .011" I usually can align the saw to .001, so I realigned it with an alignment plate and got it back to .001. But when I put on a blade, I found out the alignment was still out .007, depending on how I rotated the blade. For example, +.005 and then rotated 180 degrees and out by -.002. And the reverse in another 180. So I figured I would check the runout of the arbor flange, which the factory specs list as having a .001 tolerance. Mine was now .002. That does not seem like a lot, but taking the radius of the flange out to the edge of the blade would increase it at least 3-4 times, which translates to a .007 wobble in the blade plate.

Also, the cut quality was certainly inferior to what it had been before. Previously, I could get a glass smooth cut-off with a Forrest Cross-cut blade, and after the dado trigger, I could see tooth marks. Also, the saw makes a slightly different sound. Like there is more vibration.

I called SawStop, and they say the tolerance for blade wobble is .010 and that I should not have used a dado with full cutters because the mechanism cannot deal with that much inertia (or momentum ... whichever!). (Note that they only recently recommend this practice, probably because the saw cannot quickly stop a spinning billet of 8" x 3/4" metal.)

I can't believe .010 wobble is acceptable, especially when the SawStop manual describes that you can get to .001. And .010 is bad. I can measure .010 without a dial indicator. SawStop said I must have bent the arbor as the flange run-out was over spec, but not bad. This is where I got into a debate with the rep as to whether .002 was only a thou., more than a thou., or was double a though!!!

Anyway, SawStop said I could replace the whole arbor assembly for $250. I made the change and was back to a thou for the runout of the blade at the edge of the blade. And no burn or wobble.

Lesson: Do not use a dado set with full chippers on the SawStop.

[Michael Burnside]

Technically the Freud box joint set is not "approved" for SawStop as it has (at least when I had it), the anti-kiclback feature. It will still work, but supposedly may not stop as fast as it should.

While I will use a dado stack occasionally, most of the time I use a Ridge 10" 1/8" box joint blade and take multiple passes as you said. Saves having to change our the cartridge. I usually only go the dado set if I have to make many (wide) dados.

I thought hard about going with a WoodPecker rip stop since it has a dado feature that I think would have made this even easier. Went with a Wixey DRO instead, which still helps with the dados, but is more useful to me in general.

Some what off topic, but I love the Ridge blade you mention. I use it almost exclusively whenever I cut dados/grooves/rebates. It's a quality blade. And team red Rip Stop is outstanding for repeat cuts or having multiple "recorded" stops for a complex project as well as the obvious dado. I've only use the dado feature once, but it was cool and pretty easy to setup. I have 4 total stops on my saw for added flexibility for the "recording" function I mentioned.

[Jim Dwight]

The one time I tried cutting dados on my PCS I was using an inexpensive Freud dado set with two tooth chippers. It was a 3/4 stack. I messed up and contacted the stack due to kickback and the cartridge did it's job. I detect no difference in cut quality or runout after this incident. So either I was lucky or smaller chippers make a difference.