Dado cutters - Please, what is so dangerous about them

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Sawdust":1q87h2cq said:
What has been proven?

The pointlessness of discussing the safety of dados

As I also stated at the start, I did search and read the threads and didn't find the answer to my question so I asked it. ... Your replies have not helped in any way, unlike others that have at least provided valuable information.

As no-one has said anything that hasn't been said before, my replies, however pointless, have added as much to sum of knowledge as anyone else's.

Cheers - this isn't personal. It just all gets a bit tedious after the tenth time it flares up yet again and round and round we go. I'll step away and ignore the thread!

Jake
 
johnelliott":1knswn0c said:
I think it is one of those situations where if people can't see for themselves what is wrong with having a unguarded dado blade in a tablesaw then there is no way that anyone else (even Scrit) is going to be able to explain it to them. That is why there have to be laws about this kind of thing.
Similar situation to when the helmet law for motor cyclists was passed. All kinds of protests, most of which were along the lines of "I've been riding motor bikes for twenty years and never needed a helmet"

All the above IMHO, of course

John

I did ask at the beginning, that if the major concern was the lack of guarding then was there a satisfactory way of guarding the cutter. I was also asking if there was anything else I had failed to think of that added an unexpected danger to the operation.

suppose I attached a steel plate to the fence that completely covered the blade and prevented my hands from getting anywhere near the cutter, would you then consider the operation to be safe?

Mike
 
jake
sorry have to agree with neil it appears to be personal. :cry:

the big problem with any forum is that questions will come around
again as people join, or forget how to get the old links.

when so many people now watch norm ( :lol: )
and see the dado head in use on a table saw it is bound to
raise questions.

safety is also a thing which will always be contentious, not least
because so many hse decisions these days appear to be restrictive
on the qualified, but as scrit has said before few get the proper
qualifications these days so better to find a way round than to lose
bits of your body because you did not think things through.

mike as i said at the beginning, with dadoes being banned over 50 years
ago in the uk, many myths have arisen, kind of like the constant
suggestion from many "qualified" people over here i meet who tell
me on a regular basis that mdf is banned in the usa.
as anyone reading american woodworker, pop wood, or fww will know
this is untrue, but the myth has grown up.

guards on almost all machines could be improved dramatically
by building your own. and for instance the so called cross cut sled
favourite in many american programmes and magazines
offers great opportunities for making safer guarding.

personally i think you are wrong about the dado blade catching and
slinging back the panels, because it is only cutting half the
wood for instance, but since in many cases people cut dadoes
in panel goods, there are better chances of catching due to what is
in the panel goods. the other thing to think about is without some form
of downward pressure, the dado will vary in depth as
you move a long board over the blades.

this will of course not be true with an RAS.

i know it is hot, and our football team did not play well last
night, but lets at least cool this off a bit :lol:

paul :wink:
 
Its a fair question, and one which comes up alot. It receives different answers depending on which side of the debate you are on. My understanding is as follows:

Dados are not banned in the UK, if you have a saw that is designed to take one then they are perfectly fine. However, such a saw is usually imported. David Free covered this topic quite well when the Great British Woodshop was first aired. The HSE legislates for business, not the home user / hobbyist. Whether the above is true in an industrial setting I wouldn't know, but the HSE website is a mine of information - some of it may even be relevant!

The original question is why are they more dangerous. Simply put, they are unable to take standard guarding, requiring a fence mounted guard or overhead guard. These are not as protective as a crown guard and do not have a riving knife. They also have a greater mass, more inertia and therefore do more damage if the worst should happen. Finally, a Dado is only one way of doing something. There are other, safer ways. Risk assessment suggests that the most safe option should be used to accomplish a task.

My understanding is that if your RAS is designed to accommodate a Dado, and you are not in an industrial setting, you are free to do so. That is my understanding rather than carte blanche to go ahead though!

Steve.
 
engineer one":2tzxh7kq said:
jake
sorry have to agree with neil it appears to be personal. :cry:

Actually Neill chopped my message to Jake because I was a little offended that he misquoted me!

I genuinely didn't think I was being offensive but if others did, then I apologise.

engineer one":2tzxh7kq said:
i know it is hot, and our football team did not play well last night, but lets at least cool this off a bit

I was in the workshop last night, keeping as far away from the telly as possible !!



Cheers
Mike
 
I saw it, and I wasn't offended.

I didn't misquote you - I didn't quote you at all - but I should have said "part of" before guard. My point stands, though. It wasn't meant as an insult, though, it is just an observation about people's personal perceptions of risk.

Anyway, I'm out of here.
 
Mr_Grimsdale":1f8ul65f said:
I use a wobble saw for slots, which is a variety of dado cutter. It's fast, clean-cutting, accurate, easily adjustable between 6 and 22 mm, dust free (compared to router), safe: it can't bind or snatch as it is cutting in a slot wider than itself. In one tool replaces dozens of router cutters and does a much better job at fraction of cost.
Weight not an issue - it's no heavier than a typical saw blade. The only safety issue is the fact that the large widely spaced teeth become invisible at speed. Could be a prob in shared workshops if careless people left machine un-attended and still on - but that applies to most machines.
I mentioned this on another group a year or so ago and it attracted mass hostility and horror - but entirely from people who had clearly never used one and probably never seen one.
Was £50 (no brand name) from local saw doctor. Highly recommended!

cheers
Jacob

I didn't know they were still available although I did see one in use a long time ago. It did cut very cleanly and I was told at the time it puts less strain on the motor than a dado cutter although I doubt this is an issue an anything other than the lightest of saws.

It did scare me because the edge of the blade was hard to see and rightly or wrongly, I like to see the blade cutting and exactly where it is going.

There was also some debate as to whether the bottom of the cut was flat or slightly curved. I thought it was flat but others disagreed.

I suppose if well guarded, it's pretty much the same as the dado cutter.

Thanks
Mike
 
Jake,

It seems safe to say that someone who removes the guard from a RAS is unlikely to be convinced that other safety precautions are worthwhile or of much importance. Given that, this thread is pointless.

This debate has been done to death and the danger or lack of real danger has been discussed at length. No-one is likely to swap sides, so why bother talking about it?

Jake, no offence, but how can a thread about safety be pointless? Sawdust wants/wanted to know why we thought dado's were dangerous. Yes you may have discussed this topic before, but after reading past threads he obviously wanted to see if anyone could add something more.

Jake, do not forget that there are sure to be many hundreds of non members, who may have just come across Ukworkshop, and who may be new to woodworking and have no idea that dado's can be dangerous. In a case such as this, Sawdust's thread is far from pointless.

Would i be right in saying that although HSE have not banned dado head cutters, they have told manufacturers that to come inline with British Standards, they can only fit a small arbor to their saws, and that because of this a dado cannot be fitted to them.

Cheers

Mike
 
Sawdust":33pmh3nf said:
johnelliott":33pmh3nf said:
I think it is one of those situations where if people can't see for themselves what is wrong with having a unguarded dado blade in a tablesaw then there is no way that anyone else (even Scrit) is going to be able to explain it to them. That is why there have to be laws about this kind of thing.
Similar situation to when the helmet law for motor cyclists was passed. All kinds of protests, most of which were along the lines of "I've been riding motor bikes for twenty years and never needed a helmet"

All the above IMHO, of course

John

I did ask at the beginning, that if the major concern was the lack of guarding then was there a satisfactory way of guarding the cutter. I was also asking if there was anything else I had failed to think of that added an unexpected danger to the operation.

suppose I attached a steel plate to the fence that completely covered the blade and prevented my hands from getting anywhere near the cutter, would you then consider the operation to be safe?

Mike

This is from Scrit's advice in the thread that Alf referred us to earlier
"Those who say they (dado heads) are safe without any training or length experience are living in a bit of a fools paradise - they've yet to encounter a knot, shake or crack in the middle of a cut. That's when it gets "interesting" as a dado head can smash a piece of timber pretty easily and having a piece of 1in oak literally explode as the dado head finds that thunder shake is the sort of experience which can ruin your composure (and your underwear, too)! -- Been there, done that and ruined the underwear into the bargain!!!!! "

John
 
What would happen if you hit such a defect with a router?
 
the router would fly, more likely than the wood.

by its very design, you tend to stand behind the wood when using a
table saw, on a router table or freehand you stand to one side
thus reducing the personal, but not the workshop risk.

paul :wink:
 
johnelliott":9gse6avs said:
Sawdust":9gse6avs said:
johnelliott":9gse6avs said:
I think it is one of those situations where if people can't see for themselves what is wrong with having a unguarded dado blade in a tablesaw then there is no way that anyone else (even Scrit) is going to be able to explain it to them. That is why there have to be laws about this kind of thing.
Similar situation to when the helmet law for motor cyclists was passed. All kinds of protests, most of which were along the lines of "I've been riding motor bikes for twenty years and never needed a helmet"

All the above IMHO, of course

John

I did ask at the beginning, that if the major concern was the lack of guarding then was there a satisfactory way of guarding the cutter. I was also asking if there was anything else I had failed to think of that added an unexpected danger to the operation.

suppose I attached a steel plate to the fence that completely covered the blade and prevented my hands from getting anywhere near the cutter, would you then consider the operation to be safe?

Mike

This is from Scrit's advice in the thread that Alf referred us to earlier
"Those who say they (dado heads) are safe without any training or length experience are living in a bit of a fools paradise - they've yet to encounter a knot, shake or crack in the middle of a cut. That's when it gets "interesting" as a dado head can smash a piece of timber pretty easily and having a piece of 1in oak literally explode as the dado head finds that thunder shake is the sort of experience which can ruin your composure (and your underwear, too)! -- Been there, done that and ruined the underwear into the bargain!!!!! "

John

This does indeed sound scary and I would not want to be around when it happened.

However, would a big router cutter be any better in similar circumstances, or what if a planer hits the same shake or knot.

Mike
 
Sawdust":8qemfj8q said:
However, would a big router cutter be any better in similar circumstances, or what if a planer hits the same shake or knot.
Mike

Yes, it would be much better surely. A) The mass of the cutter is much less B) the rotational speed of the cutter is much less, especially if its a physically larger cutter C) the user is normally holding the router with two hands D) if its on a router table, then more than likely then holddowns are being used. (or are at least available). With only the depth of the router bit itself in the wood, once that is lifted (forced) ripped, or however it exits, it is doesn;t continue to exert any force on the router, and hence its safer. The user normally has access to the power switch, possibly quicker than getting a hand on the off button. The router cannot "pickup" and smash the wood into the user. Just a few reasons - not neccasarily all true, but all possibilities at least.

Adam

On a planer, the the infeed and outfeed tables are set to a different height, the wood cannot be dragged into the cutter as the tables prevent this, and the balde cannot normally be signficiantly exposed - so its only taking light cuts
 
From the Axminster Product Decsription
N.B. These wobble saws are intended for use on spindle moulders only.

Andy
 
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