# Best option for cleaning up dados?



## bbasiaga (Dec 8, 2012)

I am planning a project that will use dados in several places. To date I have been able to use my small router table to cut dados, but these pieces will be larger and too difficult to use the router table on.

I am thinking I will get a Dado set for the table saw, which in theory means I will also be able to more closely match the Dado to the actual plywood thickness. I have heard that Dado stacks don't leave as clean a cut as router bits and may require some cleanup.

To clean them up I thought it would be a good excuse to get a rabbit plane/shoulder plane. I see the Veritas and Wood river offer a 1/2" wide and 3/4" model. Lie Nielsen offers a 5/8" and 3/4".

The plywood I plan to use is nominal 3/4. Would I be better off with the 1/2" plane in case the plywood is a bit thinner than nominal? Maybe I am over thinking it. Was originally set on the 3/4" but then started to wonder what the overall most useful size would be.

Thanks

Brian


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## Redoak49 (Dec 15, 2012)

The 3/4" is too wide.

I have the Veritas medium shoulder plane and love it. Works great for what you are doing.


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## MadMark (Jun 3, 2014)

3/4" ply is often 23/32. The router will gve the best results. A hand router with a guide bar is in order.

Dado blades tend to be rough on plywood. Tape the edges to reduce tearout.

M


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## bbasiaga (Dec 8, 2012)

Im actually going to dado in to hardwood to accept a piece of plywood. So if the ply is 23/32, im thinking the 3/4 (24/32)" plane is too wide…especially considering the blade is wider than the body. Right?

Brian


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## jmartel (Jul 6, 2012)

For this application, I would think that a router plane would be better suited for it. Much easier to accurately control depth as well. Plus, it's a bit cheaper.


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## TheFridge (May 1, 2014)

I'd go with a router plane. Way more versatile.

Just let me ask this question: whether it be edge handing or face frames will the joint be seen?


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## paratrooper34 (Apr 27, 2010)

Router Plane is best bet for cleaning up dados. They have depth adjusters that will make them all uniform; something you cannot do with a shoulder plane.


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## shampeon (Jun 3, 2012)

The Paul Sellers "poor man's router plane" is a chisel driven through a block of wood. But a router plane works well, as does a shoulder plane.


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## bbasiaga (Dec 8, 2012)

Good feedback so far. I will have to look in to router planes.

To answer the question, the end of the dado will not be seen in this application. It will be behind a face frame. I will have a rabbet on the ends of that face frame with a panel setting in it that will be seen.

Brian


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## hotbyte (Apr 3, 2010)

One of these? Exact width do jig

Also like idea of router plane.


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## TheFridge (May 1, 2014)

Router planes are ridiculously useful tools.


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## gfadvm (Jan 13, 2011)

Dados cut with my Freud Box Cutter Set require no clean up at all.


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## jmartel (Jul 6, 2012)

I've got the veritas router plane, and it is fantastic. Also by far the best way I've tried so far to cut out mortises for hinges. I'm not as good with just a chisel for getting a flat bottom.

http://www.leevalley.com/US/Wood/page.aspx?p=52609&cat=1,41182,48945&ap=1


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## knotscott (Feb 27, 2009)

If you get one of the top dado sets, you really shouldn't have enough cleanup to really worry about. The best sets generally leave really smooth bottoms, but will have very slight bat ears on each edge left by the beveled teeth of the outside cutters…they're often barely noticeable, and many people don't even know they're there. My guess is it won't be an issue if you go with a set like the Infinity Dadonator, Forrest Dado King, Ridge Carbide Dado Master, Freud SD508….those sets will run $200+. The DeWalt/Delta 7670 set isn't quite to that level, but is better than the other $100 sets I know of, and may also be just fine without additional cleanup…that one runs in the $120 range.

Here's a look at a bad cut from a cheapie set like HF set: 









Here are examples from a better set like the Oshlun or Freud 208 (< $100):
















Here's a cut from the DW7670 set (I don't have an example from an Infinity, Freud 508, Forrest, or Ridge Carbide, but IME their cuts are even better.)


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## bbasiaga (Dec 8, 2012)

Wow, those are great pics. That Dewalt set seems like a pretty good middleground. I started reading up on outer planes. Except for the end grain (is it the cheek or the shoulder) of tenons, it seems like it could do anything I was expecting to do with the shoulder plane, and a whole lot more. Still need to do some digging though. The Veritas and the Lie Nielsen both seem nice.

So did someone say you can't or shouldn't cut dados in to plywood with a dado blade?

-Brian


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## MadMark (Jun 3, 2014)

Plywood chips no matter what you cut it with. Tape the edges of the cut before final cut to minimize the tearout. Test on scrap 1st.

M


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## knotscott (Feb 27, 2009)

You can definitely cut plywood with a dado blade. Done it many times. That's where the better sets really shine. Modern homecenter plywood is mostly crap, but you can still get surprising results with a good dado set. Most of the tearout in a dado will be at the exit. A backer board and/or tape can help. The pic from the 7670 is plywood.


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## wapakfred (Jul 29, 2011)

I agree with all the pointers given above, but if for some reason you want to use a router to either clean up the dados, or make them a little deeper, or just stuff another router bit in the till…these "dado clean up bits" are really handy to have. But I have to admit, having an excuse to buy a router plane is a good thing.


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## rwe2156 (May 7, 2014)

A new // freshly sharpened // high quality dado set will cut plywood crisply. 
However if concerned with tear out you can knife in lines prior to cutting.

But router plane +5 I think every one should have one! Fun to use, too.

You can use them on tenons by either keeping pressure on one side of the plane or by placing another piece of wood next to straddle.

As Fred mentioned the bottom cleaning bits with a bearing work quite well.


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## BillWhite (Jul 23, 2007)

Stanley #71 router plane. I paid $20.00 for a pristine one. Just polished and sharpened it. Works like a champ.
Bill


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## xeddog (Mar 2, 2010)

I have had several experiences cutting dadoes in plywood and other materials. My first saw was a Craftsman contractor saw, and I used a Freud SD208 dado set. With that setup, the bottom of the dado always needed a LOT of cleanup. I used both a router plane, and a dado clean-up bit in a handheld router to do the cleanup, both with good results. Thenl I had a brainstorm. I found that the arbor in the saw, and the hole in the dado set weren't quite the same size. I also found that if I cut a piece of packing tape and wrapped it around the saw arbor, all of the cutters in the dado set fit a lot better and the bottoms of the dadoes were clean. Except, of course, for those &^%$# devils ears. After that, neither the router plane nor the clean-up bit were necessary.

My next saw was a 1996 PM66. When I bought it, the seller threw in a once used Freud SD508 dado set. Around this same time I saw plans for a router jig to make dadoes. Now, if I have just one or two dadoes that need to be cut, I will use the router/jig combo UNLESS the two dadoes need to be perfectly aligned with each other, or are too long for my jig. Then I will use the table saw. But the point of this paragraph is that with the PM66 table saw, the dado set fits perfectly onto the saw arbor and the dado bottoms are very nearly perfect. So close that I do not usually need to clean them up, and if I do I will glue a strip of sandpaper onto a sized block of scrap and sand them to perfection. But even this will leave those &#$#) devil ears.

So, for cleaning the dado bottoms, it will depend on how well your dado set fits onto your saw arbor. If it is a little loose then your dado bottoms will show it. If you can find a way to get the cutters to fit snugly onto your arbor you most likely will not need to clean the bottoms. Most dado set manufacturers will machine each set to the exact tolerances. I have heard that since all of the components of the dado set are matched, you most likely cannot swap cutters even from a set from the same manufacturer.

As for the devils ears, I have read where people have ordered a dado set with a special grind to eliminate those ears. If I ever order a new dado set, I will do that because I HATE those things. A custom grind dado set would also allow much cleaner tenons and rabbets should you cut them on the table saw.

Just my nickels worth,

Wayne

Oh, almost forgot. Regarding the plywood chipping, a good quality dado set will do a good job in plywood, but you should still take precautions like taping, etc. Some plywoods are worse than others (birch for example), and some will cut cleanly.


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## wapakfred (Jul 29, 2011)

I understand the hatred of the devil's ears, but that's not the blade companies trying to piss us off. They have a purpose in getting cleaner cuts especially cross grain on plywood. You see the same thing with an ATB blade if you just cut a kerf 1/2 way through a piece of wood. Some sets are worse than others, and Knotscott has the comparisons, but they do exist for a reason.


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## bandit571 (Jan 20, 2011)

Maybe a chisel plane?


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## bandit571 (Jan 20, 2011)

Or a Stanley No.39 the right of your dado?


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## xeddog (Mar 2, 2010)

> I understand the hatred of the devil s ears, but that s not the blade companies trying to piss us off. They have a purpose in getting cleaner cuts especially cross grain on plywood.
> 
> - Fred Hargis


I understand the need for them, but they still irritate me in dadoes and tenons. In dadoes they are not too pronounced and only me or another woodworker would even know they were there. If you want LARGE ears, use a Freud Hi-ATB blade, but crosscuts are usually baby butt smooth.

Wayne


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## nhdave (Jun 18, 2015)

Router plane. It'll come in handy more times than you can imagine.


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## bc4393 (Apr 10, 2015)

Use a good blade (flat teeth) and the dog board method and just do them on the table saw if the pieces are small enough to use the fence. Perfect fit for the shelf material and chances are higher that you already have a blade that'll work.

https://books.google.com/books?id=baylBwAAQBAJ&pg=PA192&lpg=PA192&dq=dog+board+dado&source=bl&ots=4AbEOeoUlQ&sig=dO8aId9ndSgvyUmwQGRhd2bVHkw&hl=en&sa=X&ved=0ahUKEwiThd6jjdzKAhXBbD4KHTvVCiQQ6AEINzAG#v=onepage&q=dog%20board%20dado&f=false


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## Cooler (Feb 3, 2016)

I have two sets of stacked dado heads. The first I bought for my table saw, and the second for the radial arm saw. The RAS required a negative hook angle. I paid about $110.00 for the first and $135.00 for the second about 10 years back. Both are made in Italy for one of the big players-Freud or CMT, I cannot remember. I will check.

Both make very clean cuts in all materials except when I mounted one of the cutters backwards. 

I cut some spacers from magazine covers. With them I can fine tune the cuts. I never taped and I never had to clean up any of the cuts.

Buy a good set and you are better off.

When I am making book shelves I cut the sides double wide and cut the dados and then slice them to size. That guarantees that the dados line up perfectly on the left an right sides. It is fast and easy.


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