what is wrong with my dado blades

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Forum topic by DonnyD posted 06-21-2012 01:52 AM 2404 views 0 times favorited 18 replies Add to Favorites Watch
View DonnyD's profile


49 posts in 2172 days

06-21-2012 01:52 AM

I bought a used frued super dado set from clist very nice blades and the price was very right, thay cut good no tearout, but no matter how i configure the stack thier is alwasy a step at both sides of the dado. like the outer blades are a little smaller than the chippers. Made me think that the set has been sharpend incorrectly thier is alot of carbite left on the blades. I wonder if i had them sharpend agian and explain my problem could thay help has anyone had this problem? here is a pic of the cut thay produce.. smaller cut is the outer blades only other is w/ 2 chippers added !!

18 replies so far

View rance's profile


4258 posts in 3158 days

#1 posted 06-21-2012 02:20 AM

Yep, looks like a sharpening(with accompanying description) would fix the problem.

-- Backer boards, stop blocks, build oversized, and never buy a hand plane--

View TheDane's profile


5423 posts in 3661 days

#2 posted 06-21-2012 02:22 AM

Have the whole set re-sharpened … outer blades an chippers … and explain the problem to the shop doing the work for you.


-- Gerry -- "I don't plan to ever really grow up ... I'm just going to learn how to act in public!"

View MonteCristo's profile


2099 posts in 2186 days

#3 posted 06-21-2012 02:22 AM

Yeah, it looks like maybe the blades were sharpened but not the chippers and now they are slightly smaller in diameter. I think a good sharpener should be able to fix things.

-- Dwight - "Free legal advice available - contact Dewey, Cheetam & Howe""

View lumberjoe's profile


2899 posts in 2246 days

#4 posted 06-21-2012 02:23 AM

I am a dado newbie, but I am learning a lot as I go along.

1 – clean your arbor.
2 – are you sure the chippers are from the same set as the super dado? I bought the SD208. from what I understand, the super dado is a tad undersized to account for nominal plywood thickness. I assume that means width (shims) as height can be controlled infinitely by the saws arbor, but I know both the blades AND chippers are different between the super dado and the SD208.

Post some pics of the blades and chippers


View mtenterprises's profile


933 posts in 2691 days

#5 posted 06-21-2012 02:24 AM

I agree. The set wasn’t joined (making all the diameters the same). Have it resharpened and it will serve you well.

-- See pictures on Flickr - And visit my Facebook page -

View knotscott's profile


8013 posts in 3374 days

#6 posted 06-21-2012 11:01 AM

It could be from a sharpening issue, but lumberjoe brings up an interesting possibility too….it could be a mismatched set.

The Super Dado is the SD506 or SD508 and looks like this:

The Pro Dado is the SD206/208 or DD208 and looks like one of these:

-- Happiness is like wetting your pants...everyone can see it, but only you can feel the warmth....

View Fred Hargis's profile

Fred Hargis

4986 posts in 2491 days

#7 posted 06-21-2012 11:15 AM

As mentioned, sharpening should straighten that out. A quality sharpening house will only do the complete set to make sure all the teeth are at the same height.

-- Our village hasn't lost it's idiot, he was elected to congress.

View William's profile


9949 posts in 2840 days

#8 posted 06-21-2012 12:02 PM

You said you bought these used?
I have a good possibility what caused the condition. I understand that is not a quick fix for it, but thought you might want to know another possbility for cause. I ran into this same thing on a different brand dado set. I also know that brands are different in quiality, but if you read on, you’ll see why this is important.
I had a set of dado blades that cut perfectly out of the box. I used nothing but the outer blades for ages for quarter inch finger joints though. Then one day I need a three quarter inch rabbit. So I set up the blades on the saw and got the exact same results you have with this set. It was because I had worn down the outer blades, while the chippers were still new. Make sense?
All that being said, be sure to explain to the skilled (has to be to fix your problem) sharpening service and they can easily fix the situation. They did mine. A word of caution, they charged me a few cents more because of the extra grinding they had to do on the chippers, but for a Freud set, it’s worth it.


View lumberjoe's profile


2899 posts in 2246 days

#9 posted 06-21-2012 12:04 PM

My SD208 has the silver coating, like the super dado (SD508). I only see the “black” coated ones in pictures, all the sets I have looked at for the SD208 are silver. The markings on the front are the same though.


View Milo's profile


869 posts in 3317 days

#10 posted 06-21-2012 12:39 PM

I had a similar problem with my Ridgid table saw. I was the arbor. The inside blade was in a shallow spot and was being “thrown” out farther than the other blades. I agree that your arbor holes may be different in the set.

If you do not believe this is the problem, email me and I can give you the number of a guy that sharpens dado sets. I met him at the Atlanta Woodworking Show.


-- Beer, Beer, Thank God for Beer. It's my way of keeping my mind fresh and clear...

View ajosephg's profile


1880 posts in 3559 days

#11 posted 06-21-2012 01:18 PM

If the chipper blade arbor holes are over-sized compared to the cutter holes, they will rotate off center and cause this problem

-- Joe

View helluvawreck's profile


31076 posts in 2865 days

#12 posted 06-21-2012 04:02 PM

I believe that is most likely a bad sharpening job. At the plant we have used the same sharpening guy for at least 25 years. He’s good and knows his stuff. We’ve purchased a dado set at an auction that was sharpened incorrectly and he straitened it out with no problem. It could be a bore problem but if there’s no unusual vibration I would say it’s more than likely a bad sharpening job. Your sharpening man can check for every possible cause. You need to give him a wood sample of the cut when you give him the set. Make sure he has the complete set.


-- helluvawreck aka Charles,

View DonnyD's profile


49 posts in 2172 days

#13 posted 06-22-2012 03:38 AM

thanx to all for the info very helpful here are some pics.

View rance's profile


4258 posts in 3158 days

#14 posted 06-22-2012 05:08 AM

William, I find that very hard to believe. :) I’m not saying you’re wrong, I’m just in disbelief as to simple wear being the only cause. Maybe to a very slight effect, but not to the effect that Donny has shown. Hey, I could be wrong. :)

-- Backer boards, stop blocks, build oversized, and never buy a hand plane--

View nwbusa's profile


1021 posts in 2284 days

#15 posted 06-22-2012 06:44 AM

If it were me, I’d get the blades resharpened and buy a new router plane. But that’s mostly just because I want a new router plane :)

-- John, BC, Canada

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