need help gettign the right dado blade for 1/4" and 1/8" dado's

[Steve knight]

15 years woodworking and I never had a dado blade. I am bidding on a job that I did on my cnc router last time. but it is so much I would save time doing it on the tablesaw. I need flat bottomed 1/8" and 1/4" dado's. I need to adjust the 1/4" so I can get say .26 or .27 with it.

[Dave Schwarzkopf]

Steve,

I'm a big fan of this one:

http://www.amazon.com/Freud-SD608-8-Inch-Width-Stacked/dp/B000089H8P/ref=pd_cp_hi_1

It's been great to me, ridiculously easy to use and adjust, (without having to screw with those damned shims).

[Steve Griffin]

Hi Steve,
I have two dado sets. A $60 cheap home depot set, and the $300 forrest set.

When doing dados with the grain in solid wood, hands down the $60 set is superior. Less teeth is better for "ripping" with the grain I suppose. Shims will get you what you want above 1/4". The forest set is better for any other operation in any other material.

For 1/8", I'd suggest a combo blade thin kerf. Two passes to get exactly the width you want.

-Steve

[Gerry Grzadzinski]

Forrest has a 1/8" WWII with the teeth ground flat for box joints and dadoes.

[Steve knight]

I will be cutting baltic birch with it. the 1/8" is with the grain the 1/4" is across but I will have a backer.
no way do I want to make two passes just for the dados with the 1/8" we are talking 3300 passes. so I sure don't want to double that.
I can cut these faster then my cnc router and it can be doing something while I make these boxes and I will get paid double.

[Julian Wong]

Steve, The Freud SBOX8 will make a nice flat bottom dado. If you need it .27 or .28, just use a shim like a stacked dado.

As for the 1/8" dado, just use a full kerf FTG saw blade. Check the specs to make sure the kerf is .125 and it's a FTG (flat top grind). One pass will do it.

[Van Huskey]

For the .125 I would suggest a Forrest full kerf WWII with #1 (flat) grind probably the 48T, basically the highest tooth count they have in #1 grind.

For the 1/4" I would get the Forrest Finger Joint set and as mentioned shim it for the extra thou or two.

[Brad Shipton]

Steve, if this a common task you might want something like a jointing blade. They come in standard widths and given your volume I bet you would like the changeover speed. Leitz, Garniga, and many other blade manuf. make these.

Brad

[Kevin Groenke]

We use an el-cheapo Kempston FTG 24T rip blade (http://www.amazon.com/Kempston-99312-10-Inch-Industrial-Coating/dp/B0013KTUQ6/ref=sr_1_fkmr1_3?ie=UTF8&qid=1287530438&sr=8-3-fkmr1) for 1/8" flat bottom grooves. Works great, price is right.

You want, I can measure the width of a cut or you tomorrow, but if it's not .125", it's +/-.002".

kg

[Alan Schwabacher]

For the 1/8" kerf, I think you want FTG to make sure the bottom is flat. For baltic birch, you'd need a lot of teeth, so the FTG ground WWII blade is the available one you want. If you don't need the bottoms perfect, a combo blade might do.

I'm pretty sure a sharpener could adjust the kerf to what you want, and even change a grind to FTG from something else. So regrinding a some dull blade you already have could be an option.

Rather than adjust a 1/8" blade, you could simply get several blades that cut slightly different kerfs. Cut, measure, and label, and you are set.

For 1/4" and above, the box joint blades from Freud or Forrest should work, with a dado shim to make it wider. If you need a little less than 1/4", a resharpened box joint blade might be a reasonable bet.