Flat bottom dado?

[Dennis Peacock]

Well....I'm in search for a dado set that will cut as close to a perfectly flat bottom as can be had with a dado set. Do any of you have or know of a dado set that will cut a clean, flat bottom? Please advise.

[Jay Albrandt]

Hi Dennis,

I had to save my money for awhile, but I bought the Dado Master from Forrest. I can't say enough about it.

Good Luck with your search.

Jay

[John Miliunas]

Dennis, I used to have the Freud SD-506, though I'm not sure they're in production any longer. I would have to believe the SD-508 is equally as good. Very, very nice flat bottoms with the 506. I currently have the Freud SD608, Dial-A-Width. Again, very smooth bottoms BUT, the outside blades leave a tiny valley right at the edge of the cutline. I think it's by design and helps to keep splintering on the edges at bay. The SD-500 series keeps it flat across the whole thing.:) Now, let me throw another one at you. I don't know how true it is, but when I was shopping for my first Freud set, I stopped into a very reputable WW dealer who carried Amana blades, among others. He very highly recommended the *Delta* dado set for less than a 100.00$$'s! :) I almost gave in, but decided to look a bit more and figured why take a chance. The Freuds are tried and true. :cool:

[Steve Cox]

One option is to build a router base with a 3/16" d by 1/2" wide wood strip down the middle. Put in a 1/2" straight bit and use the wood as a guide for the sides of the dado. You can then cut the dado on the TS and make a clean smooth bottom with the router. Takes literally seconds to clean a dado. Just a thought.

[JayStPeter]

It seems to me that every time I read answers to this question that nobody makes a blade that doesn't have some light groove along the edge. I'd say to use your current dado set and follow it up with something like this (http://www.lie-nielsen.com/tool.html?id=half)

Another common answer seems to be to get your dado blade sharpened and specify that you want perfectly flat bottom dados.

BTW, I have a SD508 and it leaves light grooves on either side. Pretty darn flat, but not perfect.

Jay

[Don Selke]

I use to cut all my dados on the table saw with a stacked dado set (Freud) with great success. I now use a router with a adjustable jig and a 1/2" bit whenever possible. This allows me to keep the table saw free for other operations. I made two jigs, one for a 1/4" straight bit, 1/4 to 1/2" dados and one for a 1/2" bit for 1/2" and upward dados. The dados have flat bottoms and flat sides with no chipping. The jig is very simple to construct, it is compact and stores on the wall of the shop. You can find this jig at the New Woodworker.com web site.

[Keith Christopher]

Router with http://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/bt_solid.html#spiral_flushtrim_anchor

installed. Man these things are FLAT. might take more time to rout a 3/4" dado but with the right jig ZERO cleanup.


Keith

[Tom Hintz]

Dennis,
I have a review of the Freud Dial-A-Width Dado at the link below. It does cut very small edges to the floor of the dado but I have yet to be able to see them in the finished project. They make a good place for a little excess glue and when all is said and one, and dried, are invisible.

http://www.newwoodworker.com/reviews/Frdsd608rvu.html

[Doug Shepard]

Forrest Dado set or routerbit.

[Spence DePauw]

Link to a bit made by MLCS specifically for cleaning out dado bottoms. The guide bearing runs on the dado wall, so no external jig is needed.

Spence


http://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/bt_dado.html

[Dennis Peacock]

Thanks for all the great info folks....but now.......let me throw a monkey-wrench into this equation.

I am making high-end boxes....I am cutting 1/4" finger joints for the box corners and I need them "clean". Cutting dados for large furniture items "ain't no big deal". It's this high percission work that's killing me...one joint at a time.!!!! :eek:

Here is the latest knife box I'm working on, it's not finished yet...but will be today. I'll post more pics later.

[Steve Cox]

In this case you want to make a box joint jig for the router table. The piece will need to be backed up but that is how to get the dados you want.

[John Bush]

Hi Dennis,
I made some finger jointed boxes using my 6" Freud stacked set and got good results. I was using some 3/8" x 11" spalted maple and even the punky areas surfaced well with the dado set. I looks like you are using maple for your boxes. Let me know if you want to try some spalted stuff and I'll send you some. Best wishes, John.

[Dennis McDonaugh]

Dennis, I use the Freud stack dado set to make box joints. Not sure of the number, but its the 8". The joints are very crisp. I made the box joint jig to fit the dado with the only the two outside cutters and no shims. It makes a joint slightly less than 1/4".

[JayStPeter]

Dennis,

I use a Jointech system for my router table that does a great job on box joints. I had an Incra that also worked well, but there were some things I liked better about the Jointech. Another option is to use pretty much the same jig you would use on your TS on your router table w/a 1/4" bit.

Jay

[Jim Becker]

Two 1/8" kerf ATBR blades stacked side-by-side (with a little shim to make up for the difference in the plate thickness from the carbide tips) would do what you want to do without the tell-tale "ears" that virtualy all the quality dado sets give you. (the very tip of the outer blades are set up to score for clean cross-cutting)

The router table is anothe option, but I'd worry about tear-out...for the figured stuff you are using, I wouldn't do this without backer blocks both in front of and in the back of the actual stock.

[bruce erdman]

If you are using finger joints, they not be high end boxes, IMHO!

[Frederick Skelly]

if you have the spare $ burning a hole in your pocket, the Forrest or Freuds mentioned are going to be hard to beat. Im tempted too.

But, remember that you can mix power tools with hand tools for less $ and get good results. Jay St. Peter suggested using a shoulder plane to flatten the dado made on your TS. In a similar vein, Id suggest a Router Plane. I bought a small one (1/4" wide) from Lee Valley last year for about $70. It works very well for me.

Anyway, its an option to consider. Good luck!

Fred

[Jim Neeley]

Dennis,

Forrest makes square blades specifically for cutting finger joints. They're a two-blade set designed specifically to do as you request. You'll need to build or buy a spacing jig nevertheless.

[Todd Burch]

Wow. An 8-year old thread.

Bruce, what is high end box?

[John Hays]

Wow. An 8-year old thread.

Yep, forum threads are like a carton of milk... always check the date before opening. :D