Using a dado blade

[Dave Cullen]

I bought my first stacked dado blade kit for cutting half lap joints in some framing lumber, and I'm disappointed in the results. Wondering if it's because the set is inadequate, or because of my technique, or if it's just the nature of the beast.

The job required half lapping 2x4's and 2x6's which were planed to just under 1-1/2" thick. I used the 3/4" stack and took multiple passes, and there are ridges between the passes (I'll post pictures later). Luckily this is a carpentry project so precision is not paramount, but still... I expected better.

This is the set that I bought.. it came in a nice wooden box :). Is it a POS?

http://www.homedepot.com/p/Avanti-Pro-8-in-x-24-in-Tooth-Stacked-Dado-Set-P0824DADO/202035223

[Dimitrios Fradelakis]

The reviews say it all...

[Jerry Wright]

My Amana set was about $200, 3-4 years ago. Make sure you have the outer blades oriented with the "peaks to the outside. Also, i still use a plane to clean up the surfaces.

[William C Rogers]

My set if Freud, but also take a small plane to cleanup. I doesn't do bad though.

[Ken Fitzgerald]

With any dado set crosscutting lumber like 2x4's or 2x6's can create less than stellar results if the material isn't perfectly flat and twist free. It doesn't take much to cause deflection which causes my hesitation on using them on plywood cabinet carcasses though I still do. I have a outfeed table in the process to help reduce that problem on cabinets!

When I built my lumber storage rack, I made a jig and used a pattern bit in my router.

[scott spencer]

Is it a POS?

http://www.homedepot.com/p/Avanti-Pro-8-in-x-24-in-Tooth-Stacked-Dado-Set-P0824DADO/202035223

Unfortunately....pretty much. :( HD's return policy is pretty good, so I'd clean it up and take it back. If they're gonna sell junk like that, they should expect returns. It's hard to find a decent set for much < $70....Oshlun and Avenger are decent entry level sets. The Freud 208, CMT, and Irwin Marples are good too. For ~ $120, the DeWalt/Delta 7670 is excellent at that price point.

[Rod Sheridan]

This is the set that I bought.. it came in a nice wooden box :). Is it a POS?

http://www.homedepot.com/p/Avanti-Pro-8-in-x-24-in-Tooth-Stacked-Dado-Set-P0824DADO/202035223

Hi Dave, yup it's a junk set.

The last dado set I bought was from FS Tools and it was about $200, perfect dadoes...............Rod.

[glenn bradley]

Hi Dave, as mentioned there are several contributing factors and expectations can certainly be one of them. Ken's statement above of "With any dado set crosscutting lumber like 2x4's or 2x6's can create less than stellar results if the material isn't perfectly flat and twist free." is dead on. You say your material was "2x4's and 2x6's which were planed to just under 1-1/2" thick." Milling 2-by material to 1-1/2" thickness would not be adequate to flatten and true any construction lumber I've seen since the 1970's so suspicion is high that the material was irregular. Even when I have managed to get dimensional lumber trued up, it can change faster than I can change my mind about using it. You say that this was a project where 2x4's would be appropriate so I think you're OK. As to dado stack performance; I'll blather on a bit.



You don't always get what you pay for and in today's market somewhere around $200 you have reached a very usable dado stack without paying extra for the name. Don't misunderstand me, you can certainly pay more for larger and/or better grades of carbide and justification for the extra cost here will vary with your needs.
Even the highest rated dado stacks leave a tiny bit of "bat ears". This is due to the outside plates being called on to cut a clean path through a crosscut. The quality of this part of the geometry (and that of the plates) is where $50 stacks and $250 stacks vary.
Softwoods do not cut as cleanly as hardwoods. Pine, fir and the like have fibers that will crush as opposed to cut even with a very sharp cutter. This exaggerates any lack in quality or condition of the cutter. Take a pass at a piece of hard maple and compare the cut to your 2-by material for comparison.
The saw's ability to run a stack comes into play. There are saws that are not rated to run a stack at all and others will state the maximum width that is estimated as safe or usable. The controlling factor here is the machine's ability to spin that big heavy assembly and not increase vibration or run out.
Control of the stock through the cutting path is also a factor. Even perfect material and a perfect dado stack will perform sub-optimally if you are running a 6 foot 2x4 through the cut with only your miter gauge to control it.


So before you condemn your stack (and by the way I curse that Chinese outfit for buying the Avanti name and using it to look like the old Freud product . . . grrrr.) give it a whirl on some properly milled hardwood stock. If you run a short piece of well prepared walnut through the stack on a sled and the cut is still not what you are looking for I would then start to question the cutter and the saw. Good luck and let us know what you find out.

[Ellen Benkin]

I have a Freud set that creates ridges that I clean up with a router plane. I guess if you want perfectly flat dados you need to invest big bucks in the dado set. I'm perfectly happy with what I have.

[Grant Wilkinson]

I would bet that Glenn's last point addresses at least some of your problem. You need a method to ensure that you keep constant and equivalent pressure on the part of the 2x that is over the dado set. There is a considerable upward pressure being brought to bear on the wood by the dado set and you need to have a feather board pushing against it to assure constant pressure.

[Peter Quinn]

I don't have experience with that set or that line, and I don't always place much weight in online reviews, often they say more about the reviewer than the product. But when all the reviews run one way......it's hard to imagine they all have a bone to pick. And when a product like saw blades are available "exclusively at......" any source other than a direct sales manufacturer....it's probably dubious. You can only buy ridge carbide from ridge carbide, but they make it and it is excellent, so they put their name on it. Can you buy Avanti elsewhere? All signs are you bought junk.

that said, TS dados aren't usually pretty to look at. My Forrest set was over $200 some years ago, the dados are very flat bottoms but they have the little bat wings from the ATB cutters, once in a while the wood sort of reacts around the blade as stock is removed and leaves a little high or low spot. Dados and tenons are by their nature blind cuts so this doesn't bother me. A little work with a sanding block, shoulder plane or rabbit plane......end of problem. Starting with flat stock (ie S4S that has seen jointer and planer) and a good dado helps eliminate 95% of the problem.

[Ray Newman]

My former sharpening service advised me that to improve dado performance, I should have the entire set "jointed" to cut to equal depth. It really improved my "economy" dado set performance, even on construction grade material. Later, had the same done when I purchased a quality carbide dado set.

At one time I read an article on dado sets and it claimed that Forrest would re-sharpen their dado set to remove the" bat ears." Again, you just need to tell the sharpening service what you want.

And I found that if at all possible, employ feather boards to hold the work down and lessen stock vibration, which will improve the cut quality. Making light passes instead of trying to hog out all the material in or two passes also helps.

[Dave Cullen]

Thanks, guys. This is what I'm getting for results -

https://farm6.staticflickr.com/5612/15455736707_f71912b0f4_z.jpg

The boards were jointed and planed as flat as I could make them without losing too much thickness. I think I lost 1/16" total, but the lumber was surprisingly straight when I got it. I made a dedicated crosscut "sled" to support the work on the table saw and made sure to apply even pressure while running over the blades. In one board I had to cut through a big knot, and that was a challenge.

In retrospect, I should probably have cut the shoulders on the TS and sliced the cheeks with my bandsaw. But I couldn't figure out how to support long heavy boards on the bandsaw table.

This is the first time in over 30 years of woodworking that I've ever used a dado set. But I guess I should have bought the "better" one. Luckily this is a construction project and not furniture.

[Larry Browning]

Thanks, guys. This is what I'm getting for results -

The boards were jointed and planed as flat as I could make them without losing too much thickness. I think I lost 1/16" total, but the lumber was surprisingly straight when I got it. I made a dedicated crosscut "sled" to support the work on the table saw and made sure to apply even pressure while running over the blades. In one board I had to cut through a big knot, and that was a challenge.

In retrospect, I should probably have cut the shoulders on the TS and sliced the cheeks with my bandsaw. But I couldn't figure out how to support long heavy boards on the bandsaw table.

This is the first time in over 30 years of woodworking that I've ever used a dado set. But I guess I should have bought the "better" one. Luckily this is a construction project and not furniture.

That actually looks pretty good to me. A few passes with a plane should clean that up pretty well. You would get some ridges using any dado set no matter what it cost. I wouldn't take it back. Who knows, you might find another use for that dado set 30 years for now and not have to buy a new set.

[Pat Barry]

I bought my first stacked dado blade kit for cutting half lap joints in some framing lumber, and I'm disappointed in the results. Wondering if it's because the set is inadequate, or because of my technique, or if it's just the nature of the beast.

The job required half lapping 2x4's and 2x6's which were planed to just under 1-1/2" thick. I used the 3/4" stack and took multiple passes, and there are ridges between the passes (I'll post pictures later). Luckily this is a carpentry project so precision is not paramount, but still... I expected better.

This is the set that I bought.. it came in a nice wooden box :). Is it a POS?

http://www.homedepot.com/p/Avanti-Pro-8-in-x-24-in-Tooth-Stacked-Dado-Set-P0824DADO/202035223
Obviously, you can spend a lot more than you did and get a better set. I have the set you have and it does the job for my infrequent needs. you do need to sometimes clean up the 'grooves' although that is an easy job with a sharp chisel. I don't share your complpaints because I did not expect a miracle for a $39 set (no wooden box).

[Earl Rumans]

The Sears Dado set http://www.sears.com/craftsman-cm-8in-stacked-dado/p-00937666000P?prdNo=1&blockNo=1&blockType=G1 is the exact same set as the DeWalt http://www.amazon.com/DEWALT-DW7670-8-Inch-24-Tooth-Stacked/dp/B0002ZU6X4/ref=sr_1_1?ie=UTF8&qid=1414429890&sr=8-1&keywords=dado+blade+set and much cheaper. It goes on sale occasionally, if you watch. I got mine on sale for $89 plus I had some shop your way points so it only ended up costing me $80. It works great and makes nice flat bottomed cuts, for the price I highly recommend it. I was looking to have to spend much more, to get a good set and I am glad I was directed to this set.

[Jim Rimmer]

I don't know your skill level or experience and by no means do I intend to be a smart a** or talk down to anyone but one valuable lesson I have learned from my time on the Creek is little things like your are asking about is what makes the difference between the cobblers and the craftsmen that work with wood. (The fact that you're asking indicates you want to reach that next craftsman level). It's hard to put it into words but I've learned from many here that you can't just cut, glue it, stain it and call it done. It's the extra time, the tweak here and there, the special techniques you learn from friends here, the use of hand tools to supplement your power tools that make your projects special. Using a had plane or a chisel to clean up these joints and make the fit come up to your standards is what separates you from the guy who cut it and glued it and makes you the finisher of a project to be proud of.

Really has nothing to do with your question. I just needed to say this to thank the folks here for taking me to a new level of skill and craftsmanship and your post triggered that thought.

[Larry Browning]

I don't know your skill level or experience and by no means do I intend to be a smart a** or talk down to anyone but one valuable lesson I have learned from my time on the Creek is little things like your are asking about is what makes the difference between the cobblers and the craftsmen that work with wood. (The fact that you're asking indicates you want to reach that next craftsman level). It's hard to put it into words but I've learned from many here that you can't just cut, glue it, stain it and call it done. It's the extra time, the tweak here and there, the special techniques you learn from friends here, the use of hand tools to supplement your power tools that make your projects special. Using a had plane or a chisel to clean up these joints and make the fit come up to your standards is what separates you from the guy who cut it and glued it and makes you the finisher of a project to be proud of.

Really has nothing to do with your question. I just needed to say this to thank the folks here for taking me to a new level of skill and craftsmanship and your post triggered that thought.
+1 to this! My dad taught me many things about woodworking and he is the primary reason I am a woodworker today. He passed away many years ago, but I have continued on learning and honing my skills to the point where I consider myself a better woodworker than my father was. I still have much to learn and skills to develop. This forum was, is, and will be a major part of that process. Thanks to all who have helped me and to those will help me in the future. Hopefully I can play a small role in helping others as they develop along the way.

[Jim Becker]

Even with the best stacked dado set you might have to do a little cleanup on those cuts with a block plane before assembly...nature of the beast. But yea...the better the tooling, the more likely you'll get great results. When I still owned a stacked dado set, it was a Forrest Dado King. Extraordinary results. I use a sliding table saw now and use other techniques for these types of cuts, such as crosscutting the shoulder on the saw and then the rips on the bandsaw. (Longer stock can be supported on a roller stand or similar that is adjusted to match your band saw's table height)

[Raymond Reimer]

Looks similar to my 10+ year old dado set from Delta. Clean it up with a plane and call it a day, would be my approach. I'm sure some sets are cleaner but I've not yet seen perfection from a dado set.