Dado cutters - Please, what is so dangerous about them

[SketchUp Guru]

It is interesting to me that if Brad's post were made on a US woodworkers forum, the conversation would be related to which brand of dado set to buy and whether one should buy a 6" or an 8". There might be a little discussion about wobble blades but the majority of responses would be suggesting stacked sets.

I would love to see real riving knives on the common saws here in the US as you have there. they make much more sense than the splitters we have here. I wouldn't like to give up the longer arbor that I have now, though.

The only injury I've ever received from a tablesaw is while I was cleaning the anti rust gunk out of one of the mitre guarge slots. Two little slits in a fingertip covered with mineral spirits will get your attention. the thing wasn't plugged in nor was there even a blade installed.

I use a dado set when that method of cutting dadoes or rabbets makes sense. I also make coves with the tablesaw which I guess would also get you killed in the UK. (he ducks. )

I'll use a router for daoes, too. It all depends upon which tool makes more sense in the specific application at the time and depending on which machine I want to set up. Sometimes I have the router table set up for something else. Sometimes its the tablesaw. Sometimes I use the router on the Rat. Sometimes the Legacy.

I've suffered more injuries from handsaws and chisels than all my power tools combined. Actually, the only power tool induced injury beside the aforementioned was pulling a muscle in my back lifting the planer (thicknesser) onto the stand. Oh and Scrit, cover your eyes. I have never had a guard on my tablesaw blade. I use push blocks, featherboards, a ZCI and splitter as appropriate but no guard. I'm not advocating this for anyone else so don't anyone get their small clothes in a knot.
You can look now.

"And that's all I got to say 'bout that." Forest. Forest Gump

 

[Alf]

I've suffered more injuries from handsaws and chisels than all my power tools combined.

So have I. But so far I've always remembered to stop before I removed a whole finger... :wink:

Cheers, Alf

 

[Sawdust]

It is interesting to me that if Brad's post were made on a US woodworkers forum....

Dave

Your point about the US forum interests me because that is one of my biggest confusion about this whole debate. To listen to some people over here, dados are more dangerous than atomic bombs and the suggestion is that you guys the other side of the pond have no idea about safety.

But my feeling is that if you guys were routinely being dismembered on dado equipped table saws, you must might say, hang on a bit these Brits are right, they are dangerous and stop using them.

Surely Americans value their fingers just as much as we do.

Having said that, the last time I was in Texas my colleague had three guns in his car, guns all over his house and a bullet making machine in his spare room!!!

Mike

 

[Mike.C]

Dave R,

It is interesting to me that if Brad's post were made on a US woodworkers forum, the conversation would be related to which brand of dado set to buy and whether one should buy a 6" or an 8". There might be a little discussion about wobble blades but the majority of responses would be suggesting stacked sets.

Thats really what this subject is all about, where you are live and what way of cutting dado's you feel happy with. Lets face it, if the HSE had never mentioned dado head cutters, and like our brothers on the other side of the pond we had always used them, this thread would not exist.

Cheers

Mike

 

[wrightclan]

I

I would love to see real riving knives on the common saws here in the US as you have there. they make much more sense than the splitters we have here. I wouldn't like to give up the longer arbor that I have now, though.

I've suffered more injuries from handsaws and chisels than all my power tools combined. )

I'll second both of those sentiments. I slipped with a chisel once and it went right into the middle of my left palm. Fortunately with not enough force to cause real damage, but my hand was sore for days.

Riving knives are the real deal, they have more to do with safe ripping than any guard.

By the way Dave,

I grew up in Elk River (actually Otsego, which I guess is a town now, but was only a township when I was growing up.)

Nice to hear from a fellow Minnesotan.

Brad

 

[SketchUp Guru]

Surely Americans value their fingers just as much as we do.

I've always been attached to mine. All eight of 'em...and my thumbs, too.

Brad, glad to find another Minnesotan here. You know, there are some Wrights on my mother's side of the family. She was from southern Iowa. Hmm....

 

[ivan]

I gather that part of the attraction of mountain climbing comes from conquering risk - no risk means no fun, no sense of achievement. Personally, that's not why I go into the workshop....so it's is of interest to me then, when because of an analysis of accidents, HSE express concern about cutting dados on a sawbench and point out that other methods are less prone to serious accident.

Using a RAS has its problems. You risk the blades running on into the work (unless specifically designed for that purpose); the wider cut pulling in more strongly than a single blade, stalling the motor and probably knocking the saw out of alignment.

 

[Paul Kierstead]

Same comments as others have made about braking, although I fail to see why, if a wheels can stay on a car under heavy braking (eg emergency stop with the wheels locked up), manufacturers can't make a blade stay on a saw where the braking is pathetic anyway.

I am sure the manufacturers could but unfortunately they don't, and the theory of what could be done has no bearing on the safety of what is done. In any case, the arbor would have to be redesigned and I suspect the taste for all new designs of sawblades is low.

I have used a Dado (3/4" wide) and a router (3/4") a fair bit. There is no comparison in forces pushed back at the operator; the saw exerts considerably more force and has a *lot* more inertia, and also tempts you to cut deeply if it is a powerful saw. That said, I am not sure it is unreasonably unsafe in the single-person shop, but it can be tricky to use, especially on the exit. I would think that an overhead guard which rides (or very nearly) on the top of the wood would greatly increase the safety, although kickback concerns would remain. Personally I would consider a tilted blade to be much more dangerous then a dado, but then my saw doesn't have a riving knife either.

Incidentally, like most canadians, my saw does not have a brake and a dado goes for a loooong time to stop.

 

[MikeW]

I would be interested to know what the others who are reading this think about this, though.

I realize I am taking this out of the context of the rest of John's questions...

Here's what I think. It's all pretty silly in one sense. Use one, avoid one. What does it really matter?

The one I used in my shop was a little shy of $300 US. I haven't used it in a few years and in all likelihood won't ever again. Heck, my table saw is in storage anyway. I don't use that either. So why haven't I used it for so long? Because the only time I did use it is when working plywood or MDF. Anything less than a foot wide and I'll use the WoodRat. Even when having a stack of parts to dado, a guided router is incredibly fast. Guided in the sense of a clamp system.

For most solid wood, I make dados by hand, which I don't use on solid wood furniture that often anyway.

So why all the babling? Well, I was asked what I thought :lol:

Really it was just to illustrate that most of my local cabinet shops where I know the owner, only use tablesaw dados cutters when also cutting sheet goods. They do use them mounted in a RAS for lumber or components less than 24" wide. Set up is faster as it cuts on the up-side.

If I were to use the dado cutters again, I too would simply get a RAS and use it. I doubt I'll use sheetgoods where I need to cut dados ever again. And if the need arises, I'll probably use a guided router as it isn't worth setting up a table saw for it to me.

As to the issue of this thread: Safety? There are inherent risk in everything woodworking related. My advice is if you are not cutting dados in sheetgoods on a consistent basis, use a RAS instead. If you will do so once in a while, use a guided router. If you do intend on cutting dados in sheetgoods consistently, look for a safer, commerical solution.

Take care, Mike

 

[RogerS]

Apart from the Xcalibur, which other table saws in a similar price range will take a Dado?

 

[wrightclan]

Apart from the Xcalibur, which other table saws in a similar price range will take a Dado?

For a fair bit less, you could buy a used Startrite, it will take up to 5/8", at a push 11/32". (There's a reduction in arbor diameter between the smooth section and the threaded section, to keep you from going any farther.)

Brad

 

[Freetochat]

The Hammer and Felder range can be specified for a dado set!

 

[RogerS]

The Hammer and Felder range can be specified for a dado set!

and how much would that be ? :wink:

 

[wrightclan]

I gather that part of the attraction of mountain climbing comes from conquering risk - no risk means no fun, no sense of achievement. Personally, that's not why I go into the workshop....so it's is of interest to me then, when because of an analysis of accidents, HSE express concern about cutting dados on a sawbench and point out that other methods are less prone to serious accident.

Using a RAS has its problems. You risk the blades running on into the work (unless specifically designed for that purpose); the wider cut pulling in more strongly than a single blade, stalling the motor and probably knocking the saw out of alignment.

What an absurd implication--that those of us who use dado cutters do it for some kind of danger-seeking thrill. Quite the contrary, as I've been saying all along it is a safe procedure, as long as you use it sensibly, no more dangerous than many other woodworking processes. And no more dangerous than many day-to-day activities. ](*,)

Brad

 

[Anonymous]

sawdust

A more appropriate question is why do you want a dado cutter?
They offer no real advantage over a router other than cutter life

They are slower to set up and change than a router cutter, do not leave as flat a bottom to the cut as the router and often require you to play with shims.

I have owned and use a Freud dado cutter set and do not consider then dangerous IF USED PROPERLY and with due care. Many injuries seem to be down to stupidity such as running 8*4' sheets over one :roll:

However, I sold my cutter set and find the router with a guide a far superior and quicker AND potentially safer method of cutting dados - I would not consider going back to a dado head cutter which takes far too much time to swap with the saw blade and set up (I would have routed them all and glued them up by the time the dado head was in the saw :lol: )

 

[Adam]

But that still does not address the issue that each of the teeth of a dado cutter are taking relatively small individual cuts,

True, but what about the inherent energy in the blade/motor of a saw vs the momentum in a cutter/router? They are vastly different.

Furthermore, assuming you are cutting a 1/2 deep dado, from the point that the saw blade tooth prodtrudes above the table, to the point it returns is just over 10cm. So, if the workpiece catches, the blade has a full 10cm to accelerate the wood over. Assuming the same corner catch on a router bit, I think (may have a dodgy calculation), that its only going to catch for 2cm (e.g. half a revolution).

So as far as I can see if the blade tips are able to catch, they have far longer to accelerate the wood, and their is far more stored energy in the table, and the blade is travelling faster.

Would you agree?

Adam

 

[wrightclan]

But that still does not address the issue that each of the teeth of a dado cutter are taking relatively small individual cuts,

True, but what about the inherent energy in the blade/motor of a saw vs the momentum in a cutter/router? They are vastly different.

Furthermore, assuming you are cutting a 1/2 deep dado, from the point that the saw blade tooth prodtrudes above the table, to the point it returns is just over 10cm. So, if the workpiece catches, the blade has a full 10cm to accelerate the wood over. Assuming the same corner catch on a router bit, I think (may have a dodgy calculation), that its only going to catch for 2cm (e.g. half a revolution).

So as far as I can see if the blade tips are able to catch, they have far longer to accelerate the wood, and their is far more stored energy in the table, and the blade is travelling faster.

Would you agree?

Adam

Yes, that's why it's more efficient at cutting a groove. It is still possible to use safely and is used safely by thousands everyday. ](*,)

I don't get your assumption that more energy behind a cutting edge makes it inherently more dangerous. If that were the case, why don't we all use 500 watt routers?

Brad

 

[johnelliott]

It is still possible to use safely and is used safely by thousands everyday.

I had stopped posting on this thread, though I'm still reading the contributions. I felt I had to respond to this particular statement, especially when it was accompanied with that emoticon, which suggested that you were having difficulty explaining something that seemed obvious to you, to others.

That statement above probably illustrates as well as anything else that has been said just what this whole argument is about- the case of most pro dado blade in table saw users is that they and others uses these things without accident every day, and that therefore they are safe.

On the other hand, the case that I and many others are trying to make is that just because an accident hasn't happened doesn't mean that the activity is inherently safe.

John

 

[Adam]

I don't get your assumption that more energy behind a cutting edge makes it inherently more dangerous. If that were the case, why don't we all use 500 watt routers? Brad

At its extreme, I can grab a dremel router and stop it without injury. I know of at least one horrific case of an accident at a saw mill on a large circular saw. With or without gaurds, a low energy item simply can't do as much damage. It applies to most things, a tack hammer vs a claw hammer. I'm not saying thousands can't use something safely every day. Its the one in a million chance where it applies. A bad piece of timber, a hidden nail, a knot, shake or other fault that could not be seen from the surface.

OK, all your point taken. How about a different perspective.

Imagine you had a piece of timber that looked perfect, you had all the guards setup, and you start cutting. Today is your unfortunate day, the world over, a thousand people were doing the same cut and it went fine. You have done this same task, on the same saw, for the last 20 years. You are confident in your own ability. Something unusual happens, something falls in your shop, the board has a nail, the missus walks in and knocks the plank, twisting it, you have a heart attack, a blackout, a fainting fit. Whatever.

Which would you rather be using. A dado cutter or a router?

As above, but its your child doing it.




Adam

 

[Kane]

Are there any figures for actual accidents available? I would say that there is a risk inherent in any activity, if you say hiking is dangerous because there's a risk of snakebite you would be right but if you calculate the odds of actually getting bitten you may not be too concerned. What I find odd is that the use of dado cutters in the US is so high - surely in the land of litigation if a tool was causing a lot of injuries because it's design was so inherently dangerous someone would have sued a manufacturer by now (maybe they have lol)