# Dado Set Depth: 6" vs. 8"



## BreakingBoardom (Dec 18, 2009)

I was just curious, what is the max cut depth for a 6" dado blade and an 8" dado blade? I was thinking of purchasing one and wondering if I really need to spend the money on the 8" set. Any thoughts on size and which dado sets work for you?


----------



## Sawkerf (Dec 31, 2009)

It will depend on how high you can raise the blade and still turn the cutter. Offhand, I would guess that a 6" cutter would cut 2" deep (or less). An 8" cutter would give you 1" more depth.


----------



## RvK (Nov 22, 2009)

IIRC, you get about 1.5" depth from a 6" set and about 2.5" from an 8". For typical projects a 6" should suffice. Also depends on your saw, many benchtops don't have the power to handle the mass of an 8" set without straining. Some people also say that the extra mass in an 8" helps to leave cleaner cuts. Don't have my practical experience with dado sets myself so can't give much more help than that.


----------



## Sawkerf (Dec 31, 2009)

Not only do many of the benchtops lack the power for a dado cutter, their arbors aren't long enough to even install one.


----------



## dbhost (Jul 20, 2009)

Just out of curiosity, why is the depth difference between 6" and 8" dado sets of any interest?

I see this question asked a LOT on various forums and always wondered…

Are you going to try to do through cuts on 4×4 lumber with your stack dado set?

Am I missing something?


----------



## richgreer (Dec 25, 2009)

I have a slightly different twist on this subject. I have the Freud SD606 dado set. This is the 6" one with the dial-a-width feature. Because of the dial-a-width feature, my depth is limited to 1.25". If I purchased the 8" version of the dado set, the depth could go to 2.25"

However, for me, I never need a dado depth greater than 1.25". I have difficulty figuring out why anyone else would either.


----------



## asthesawturns (Aug 23, 2009)

through dados? I have a 6" that I mounted on my bench top craftsman, could only cut about a 1/2 wide, so it did save a little time, except that it would trip the onboard circuit breaker (craftsman tools sometimes have that) I didn't even think about touching the little red button until I had it all apart and was ready to take it in for service. I have heard that the 8" dados leave cleaner cuts. Good luck


----------



## 559dustdesigns (Sep 23, 2009)

BreakingBoardom, 
I've got an Amana Tool 8" stack dado set model #658030. I really like this set the out side blades have 24 tpi.Its came with the shims with it. I guess the Forrest set would be better. But this set does everything I need. I'd get the best thing I could afford. I used to have a cheap Craftsman 8" set about 7 years ago when I first got in to making dust. This set is my friend's at the moment he got it when he bought a used Jet saw. It came from Ideal saw works of Fresno, originally. It was brand new and I've been the only one to use it. I have been twisting his arm to trade me something for it. Hopefully it will soon become my own.

As for 8" vs 6" not sure I have ever needed to cut the full deep with the 8" set but I've never used a 6" inch set before. Probably you could measure from the center of your saws arbor to the table with the arbor all the way up to calculate approximately how deep you could get out of a 6" vs an 8" blade. The deepest I've cut with this set was about 1" with two passes (cut on the table legs of a resent project). For most operations a dado in a panel is only at most 3/8" deep, which can be done with a 6" for sure. On a small saw, a guy might consider the smaller set. Seams like it would be easier on the saw to turn less blade. Hope this is helpful as this is just just my opinion.


----------



## stevepeterson (Dec 17, 2009)

I use a dado on my RAS to notch 2×4s for building workbench frames. The depth of cut is often 1.5" or even 2". It is much easier to hog out the wood at one machine rather than set the depth to cut one side, then change the cut depth to make another cut at 90 degrees, or use chisels to clean up the notch. The RAS also allows fine tuning the depth of cut by turning the handle a small amount.

I can imagine exceeding the limits of a 6" dado.


----------



## Gofor (Jan 12, 2008)

If you have the power to turn it, an 8" has more speed at which the tooth strikes the wood. This means you may get a smoother cut at the same feed rate. However, a more expensive set 6" with 4 tooth chippers will be better than an 8" with 2 tooth chippers. I, too, use mine to notch heavier lumber, so am glad I have the 8" and the extra 1" depth of cut.

Go


----------



## marcb (May 5, 2008)

Even when you're not going into thick lumber if you have a 6 on a saw with a slightly limited depth of cut to begin with then use 3/4" plywood to build a jig you're scraping by with 1/2" of depth so you can't finger joint thick boxes/drawers/etc.

Not the worst downside, but I've seen it bite someone.


----------



## cliffton (Dec 18, 2009)

if you ever use a sled to make your cuts you will appreciate the 8" dado.


----------



## PineMan (Jul 23, 2008)

It all depends on how deep is the deepest a dado you want.


----------



## knotscott (Feb 27, 2009)

The difference in price between the two sizes is often minimal, but the selection is much greater for the 8 inchers, which improves your odds of finding a great deal. If cost is the driving factor, IMHO you'd be better off using a router than the cheapest dado set you can find.

The extra height capacity is rarely used but can be handy, especially if you were to use a crosscut sled that eats into that capacity. There has been one time that I've need a very deep groove and actually ganged 3 ten inch blades together.

Rockler recently had the Oshlun 8" on sale for $60 shipped, which was actually cheaper than the 6" version….I haven't tried this set but it's getting good reviews for very good performance and excellent value. The DeWalt/Delta 7670 has been on sale from Grizzly for ~ $90…excellent deal IMHO. The Infinity Dadonator is the cat's meow…[email protected] $180 it's not cheap but is very tough to beat.


----------



## BreakingBoardom (Dec 18, 2009)

Yeah, I saw that Oshlun set on sale and that's the one I was leaning towards. It's not on sale at Rockler anymore , but still cheaper and seems to be a good set as per reviews. And I do intend on using sleds on occasion so the 8" may be the better option. Thanks for all the comments. I'll probably end up going with an 8" version so I won't have to worry about if I'll have enough depth. Hopefully I won't need to gang together 10" blades like knottscott. lol.


----------



## 8iowa (Feb 7, 2008)

Matt:

I have the 6" Oshlun set and it cuts beautiful dados for me. If your saw is designed to run on a standard 120V, 15 amp recepticle, then it is considered "underpowered" by the blade manufacturers. With this type of saw, the 6" dado set gives you greater cutting torque at the teeth, and makes it possible to do deep and wide dados without stalling the saw or tripping breakers.

For the more powerful saw, like 3 to 5 HP the 8" set would be preferred.


----------



## knotscott (Feb 27, 2009)

Holbren's got the Oshlun sets and is a great supplier with low shipping. "SMC10" or "BT310" gets 10% off.


----------



## cliffton (Dec 18, 2009)

regarding the "underpowered" designation, I called ridgid about my R4511 and they said, its not underpowered, use a 8 inch.


----------

