I would guess because some people attempt to do too much with them and are subjected to powerful kick back forces. Plowing a 3/4"x3/4" dado through oak is probably overdoing it.

The way I use them, I've never had any incidents. I just keep the cuts shallow enough that I'm not feeling any strong resistance to the cuts. Deep dados are done in multiple passes.

 

I've never had any bad incidents using a dado set. I'm curious to see what the responses are to your post. Like JAAune said, using a dado improperly can lead to problems just as with many other tools.

 

Probably because of the amount of material removed in the event of an accident….a full dado stack could really mangle flesh.

 

Using a dado blade can be as dangerous as using a plain blade, but why such a strong reaction by European safety associations? I can just see "VERBOTEN" printed in saw owner manuals.

 

What scott said.

 

big ass blade + large potential for kickback

 

you keep hearing nonsense

in my experience & as limited as some might think that is

they r as safe as apple pie

the blades are never a problem

people are

 

"VERBOTEN" is "forbidden" in English for those that haven't looked it up yet. My only guess is that the safety police in Europe are jumping on the US attorneys band wagon of thinking all consumers are entitled to be compensated for their carelessness. I assume their reasoning is that you have to run it with the guard off.

 

They are perfectly as safe as any other tool if you are careful and use common sense.

 

speaking of dadoes and potentially being unsafe, I have a question…
Im building a simple tv stand that will have one shelf in the middle. This shelf will be glued to the sides having dadoes about halfway up. My question is as follows, is it safe to cut the dadoes (for 3/4" plywood) crosscut wise on the table saw using the fence?
Before you think me a noob about to do something unsafe let me clarify the following, the pieces that will get the dadoes aren't actually that much longer than they are wide: 20"X17" with the dado being put up about halfway up the 20" length. I have a stacked dado set that I just got, but wanted to get others' inputs before I try this. Otherwise I do have a 1/2" router bit that I could use with two passes but it just seems like that would be much more of a hassle since I dont have a router table yet.

 

Europeans love their riving knives which don't work with dado blades.

 

Everything we use can be dangerous if you aren't careful. That's why woodworkers are very common in the Emergency Department. Know your guidelines and follow them.

 

In addition to taking a bigger chunk of flesh, the skeptic in me also thinks someone who was well positioned to profit from it probably made tons of money by passing those laws in Europe. Greed and the urge for the few to control the many is pretty is an ugly part of human history.

 

Dado sets are perfectly safe… As long as you're using them on a Saw Stop.

Sorry. Couldn't resist.

 

In the past 5 years I have been using my grandfather's craftsmen table saw and it has a ¾ hp on it .
But I do all my dado's with it but I only go a ¼ " deep and a ¼ " wide and that's Oak too. I wont try this on my big saw it has a 2 hp .

 

Isn't harder to adjust the height of a dado, (the depth of the cut), on a table saw? I use a router table. It has a lift with a measuring wheel and I can precisely set or adjust the depth of the cut. On my table saw, I turn the crank and have to manually measure the height of the blade. I know a TS would be faster once set.

BJ

 

I personally haven't had any bad problems with dado blades. I would say that it is important to keep them sharp. Of course that goes with any saw blade.

helluvawreck aka Charles
http://woodworkingexpo.wordpress.com

 

I've never even had any safety concerns with dado stacks on my TS. I use a sacrificial fence, featherboards, and push blocks to keep control of the stock, and limit the depth of cuts.

I'd rather take two, three, or four shallow cuts to get to the depth I want than try to plow out the full depth in a single pass.

I'd like to get hear from some of our LJ brothers & sisters across the pond on this issue … I have always wondered why myself.

 

dado blades has added risk compared to regular blades for the following reasons :

1. dado blade full width could mean that the nut tightening the blades on the arbor doesn't have enough threading to and could potentially come loose (abnormal - and if you follow proper guidance should not be a factor - but done by someone less educated, and this scenario is a potential reality)

2. no splitter/riving knife can be used (properly) which increases the risk of a kick back as there is nothing behind the blade to prevent wood from being pushed onto the back of the blade

3. non through cuts - requires the removal of blade guard on 99% of factory supplied TS (unless you have an overarm guard which are usually after market guard solutions). again, reducing the amount of safety protection one run this TS with

 

Well BJ I dont think so its easyer than a router but I set my blade at a 1/4" to start and take it all out at one time.

 

Id like to see the european safety regulations concerning table saws and dado blades. Otherwize its hard to tell fact from fiction. I did not find it but here is some type of summary of the UK table saw safety regulations.

http://www.hse.gov.uk/pubns/wis16.pdf

"Rebating and grooving. A circular saw should not be used for cutting a rebate or groove unless the blade is effectively guarded. This is because the normal saw guard cannot be used"

(More info might be on http://www.hse.gov.uk/woodworking/wis.htm)

 

@rg33: Based on the size of your work piece, I think you would be okay using the fence. If it was much longer, though, I would use a miter fence or a sled.

 

I had heard this too, and am interested and agree with what most of the comments on here have said so far. Here are a couple observations from someone who uses my dado set a lot.

1. Riving knives and blade guards go out the door pretty much. (+1 PurpLev)
2. Removing more material in one swipe can be dangerous if done improperly.
3. Heavier blades result in more wear-and-tear on your TS motor, especially if you take deep cuts.
4. My saw (Ridgid R4511) at one point had a recall because dado sets were being spun off the arbor and being thrown around the shop. Mine wasn't an affected serial number, but it certainly gave me pause for a moment the first time I spun a dado after reading that. Not really a problem with dadoes in particular, but rather with the saw itself I guess.
5. The older model dado blades (that oscillate as they spin, don't remember the name) freak me out. Not for any particular reason I can think of, but they scare me a bit.
6. They are harder to have ZCIs for. A while back I batch cut about 10 Zero Clearance Inserts of my TS, and most of those are now cut for different width dadoes. I always have a spare blank or two that I can dedicate to a random width dado if necessary. But if you don't have the time invested in making many ZCIs and having a few blanks around, you might be running a dado with an oversized ZCI, or even worse, no insert at all. Can't even imagine how scared I would be to cut a dado without a TS insert.

 

I would guess the reason is wanting to keep a lot of downward pressure at the point of cut. One mis-step and your fingers are vulnerable. When I'm in doubt I borrow the push pads from the jointer. As for adjusting height, I keep a collection of cut-offs that I marked with their thickness…place the desired one next to the blade and raise lower until the highest tooth is even with the top.

 

Because there is not through-cut, the risk of the wood binding on the blade is nearly non-existent (i.e., the workpiece portion that has already been cut cannot collapse on itself as it is not a through-cut). One if the projects that I posted are shelves, that include 3/4" x 3/" dadoes cut through Padauk on my R4512 saw with Freud SD206 set - I took it slowly and felt no unusual resistance.

I agree with Knottscott - a cut with a dado set at full width/depth is sure to mangle an awful bit of skin and bone.