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Why no riving knife on American saws?

KiddervilleAcres's picture

I don't understand why American tablesaw makers have taken so long to realize that a riving knife is perhaps the safest and most flexible anti kickback device for a tablesaw.


We have all heard the extollations ( a new word?) of its benefits.  And I would venture to guess that it is a device that would not impede the use of other fixtures we use on our tablesaws, i.e. crosscut sleds.


Also, I can't for the life of me understand why someone hasn't come up with an after market solution?  Why should we woodworkers have to stick dowels into the zero clearance throat plates we woodworkers make in order to make our tabesaws safer.  It seems to me that here is a chance for someone to really make some money and benefit a lot of folks in the process.


It just seems to me that a riving knife is quite simple and would be a benefit to all tablesaw users.


Regards,  


Regards,



Bob @ Kidderville Acres


 


A Woodworkers mind should be the sharpest tool in the shop!


Edited 7/20/2007 8:36 pm ET by KiddervilleAcres

Bob @ Kidderville Acres

A Woodworkers mind should be the sharpest tool in the shop!

DonaldCBrown's picture

(post #100906, reply #1 of 64)

Bob-

I'll treat your question as stated, although I suspect you already know that a riving knife cannot simply be stuck on the inner workings of a Delta-style table saw. The Unisaw blade-raising mechanism follows a circular path, so a riving knife, being farther from the axis of rotation than the center of the blade, would rise above the top of the blade as the blade is raised.

European table saws use a linear blade-height adjustment mechanism, so the riving knife remains at the same height relative to the top of the saw blade throughout the adjustment range. Equally important is the fact that the riving knife can be located very close to the saw blade. That means that the riving knife will keep the kerf open no matter that stresses in the timber might cause the the kerf to close the gap. A "splitter", located maybe a foot farther back from the blade, does essentially nothing for safety.

The Delta Unisaw was first sold at about the time that the DC-3 was the latest in airline transportation. One would suspect that development costs for Delta and its imitators had been recouped many decades ago. Why the manufacturers are reluctant to design a new model that incorporates a riving knife is beyond me. But I suspect that they have counted their beans to indicate that their sales do not justify a redesign.

As an aside, the straight up-and-down motion of the European riving knife has another safety benefit that is not often mentioned. A blade guard that is attached to the riving knife also follows the blade, so it can be left in place through all cutting adjustments. I am excluding dado-blade operations in this discussion.

KiddervilleAcres's picture

(post #100906, reply #2 of 64)

Donald,


So, am I to understand that the almighty dollar has struck once again. 


I don't mean to diminish or cast disregard on your response but if so, that is a sad reflection on our manufacturers concern, or lack thereof for the safety of their customers, in my humble opinion.


Kinda like Bush trying to eliminate funding for PBS.  No I don't want to turn this discussion into a political Cafe!  Sorry, I got carried away I guess.


It just irks me that there is a safer way to use tablesaws and with all the technology available.............


I'll be honest.  I have a Delta contractors saw and the splitter has a half a$$sed attempt at a splitter/riving knife that is basically junk with respect to alignment to the blade.


 



Bob @ Kidderville Acres


 


A Woodworkers mind should be the sharpest tool in the shop!


Edited 7/20/2007 10:22 pm ET by KiddervilleAcres


Edited 7/20/2007 10:27 pm ET by KiddervilleAcres

Bob @ Kidderville Acres

A Woodworkers mind should be the sharpest tool in the shop!

DonaldCBrown's picture

(post #100906, reply #5 of 64)

Bob-

"So, am I to understand that the almighty dollar has struck once again."

Why yes. From both the buyers' and the sellers' side. A Unisaw or its imitators is incredibly inexpensive in today's market.

"...if so, that is a sad reflection on our manufacturers concern, or lack thereof for the safety of their customers, in my humble opinion."

What about the partner of the manufacturer in this transaction, the consumer? Every time a safety feature (e.g., the Sawstop blade rotation arrester or even a Euro-style riving knife) is brought up in this forum, how many responders tout personal working habits as the only worthwhile safety device? Consider all the discussion about riving knives and such on this forum: Do you really believe that the manufacturers are cynically conning the table saw buyers? Or are fully-informed buyers opting for the remarkably inexpensive table saws without riving knifes and other routine safety features?

It's hardly a cartel of Delta-like saw vendors out there. There is now a sizable number of alternative suppliers: Mini-Max, Felder, Hammerer, Rojek, Laguna, all offer a variety of saws and combo machines that meet European Community safety standards. Sadly,most consumers choose affordability over built-in safety.

Hastings's picture

(post #100906, reply #12 of 64)

Don:

"…how many responders tout personal working habits as the only worthwhile safety device?"

Anyone who has experience in working with things that kill, knows that safety goes beyond the technology that makes an inherently dangerous activity somewhat safer. Safety starts with the right mindset, but while that is necessary, it is insufficient by itself.

It's like saying I don't need a seat belt because I always obey speed limits and drive very carefully.

Unfortunately, we in the USA have to pay a premium for all of the "euro" safety features. As Lataxe pointed out in another post, there are many more choices and price points there, only the high-end stuff finds it way here. It's not helped by the weakness of the dollar.

Regards,

Hastings

PS My experience with things that kill was as a gunnery officer in a tank regiment. An entire turret crew was killed next to me during practice firing.

SARGEgrinder47's picture

(post #100906, reply #16 of 64)

So... if manufacturers add a riving knife to the saw as the Euro's, do we rejoice and declare ourselves......


 Safe.. Safe.. Safe at Last?


I personally don't think so. A riving knife is only one stop on the road to safety. It keeps the stock from pinching the back of the blade when reactionary stock is encountered that has the tendency to close on the back of the rear teeth.


What does it do to combat stock from binding and twisting when that same reactionary stock has a tendency to open toward the fence that extends beyond the cut... then rebound back toward the rear teeth of the blade? So.. you put a riving knife on the saw and you still leave 50% of that particular problem of reactionary wood un-covered and deem it safe?


If your stock does bind on the dangerous rear teeth and rise up, is the plastic substantial enough to stop the launch. The riving knife won't stop an up movement. Is the thin plastic on top substantial enough to do so? Was that considered when the riving knife was designed for a particular saw by the manufacturer?


If you are working with long, thick stock and it gets squirrelly and out of hand due to it's mass of weight distribution, will a riving knife eliminate that problem? Or perhaps we should consider full support (under.. over.. around.. in every direction to counter that from happening?


And don't get me wrong, I fully support riving knives. And as Steve stated, there will come a point that we will see them on all saws when the manufacturers agree to do it together to keep prices fair with the engineering design changes.


I have a TS with a riving knife.. I have one without. If we all just bought Euro saws with riving knives, 80% of current WW hobbyist would have to find a new hobby as they are economically ruled out of having a TS.


What can the current hobbyist do to be able to afford safety. Do they have to wait till the manufacturers make the switch to purchase or hope their lotto ticket comes in and get the current Euro at their lofty prices?


And what about those millions that already have a U.S. saw with the standard fare on-board. Should they declare it totally worth-less and sell it for scrap metal? And then go Euro or wait till changes are made here in the U.S. so they can afford a riving knife and be safe?


I say neither.... I say understand what causes kick-back and eliminate those factors and you can do it with what you currently have. It will require a little thought and field expediency. Or have we lost the knack that our fore-fathers had to take what you got and make it work?


A riving knife is only part of the answer to safety with a TS. If you only consider a riving knife without considering the other elements, you have over-looked other key elements and are not safe!


I run a re-conditioned Uni-saw I got rather cheap. I also rip 10'-14' lengths and wide stock very frequently. But... I consider my operation as safe if not safer than if I had a Euro saw with a riving knife. I added a substantial crown guard over-head.. a short fence to the right and springboard to the left. Extensions to accommodate long stock fore and aft. A plastic shield in front of the substantial crown guard that not only won't allow my hand to get near the blade, but give excellent protection from fine dust which is just as important in the long run to safety as keeping fingers today.


 My splitter won't ride up and down with the blade, but it does tilt and the crown guard I added will ride up and down with the blade in a matter of a few seconds adjustment as I made it do so with field expediency. The guard or splitter can come off the saw in under 30 seconds. Let's not say "quick release", we will say semi-quick release. All done with what I had, scrap and a $25 purchase of a dust shield.


So... I am not waiting for the manufacturer to bring safety to me... It is my responsibility as I see it and I attacked the problems with "hot pursuit" before they did with their hesitancy to address the matter. And all in a nicely wrapped package of what I had.. scrap.. a $25 dust shield purchase.. thought and field expediency. And so can you.


Safety is much more complicated on a TS than just a riving knife!


So... "What-cha waiting on".. Xmas or the manufacturer?  :>)


Sarge.. john thompson


Edited 7/21/2007 12:18 pm ET by SARGEgrinder47

Sarge..

Woodworkers' Guild of Georgia

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Lataxe's picture

(post #100906, reply #17 of 64)

Sarge,


You make many relevant points and it is true that a riving knife is just the begining of what might be considered a safe saw (read "foolproof"). 


Hold-downs integral to the fence are a great help, as is a guard that moves with riving knife.  In essence, it should be possible to fall over the tablesaw without contacting the blade; to shove your fingers at the blade with something to stop them (but not the wood) and to have any amount of reaction wood without the kickback occuring


I believe my saw achieves this condition except for the possibility of forcing fingers under the guard and around the hold-downs (although I would have to try very hard).  For this reason I would also like a sawstop mechanism in the saw - not yet available to we Europeans (so you Americans are ahead there).


The blade following riving knife is set to the shape of the back of the blade and 3mm from the teeth tips.  The riving knife is a mere 0.2mm thinner than the blade kerf.  When the wood closes up at the back, it nips the riving knife (on both sides) not the blade teeth.  The saw merely labours a bit to tell you it is hard going as the kerf closes up.  Out comes the wedge and the cuting is resumed.


Even were the blade to grab the back of the wood in the 3mm between the teeth and the start of the riving knife, the hold downs will prevent the wood kicking up, as will the guard, which is attached to and moves with the riving knife.


In short, the saw I have (a Scheppach, but typical of European saws) comes with a good riving knife and guard.  It's fence and tabletop has T-slots to mount hold downs, which Scheppach sell as an extra (greedy men).  I have devised my own from Lee Valley kit (a lot cheaper and more usuable).


Believe me, the saw is foolproof (except for that sawstop thang).  I am a fool and here I am still fully digited.


Lataxe

SARGEgrinder47's picture

(post #100906, reply #18 of 64)

Good day Lataxe...


I believe that your saw meets safety requirement also. I have seen your saw and many more of the English and Euro's advertised in Furniture & Cabinetmaking (your countries version of FWW) which Richard Jones made me aware of. For that matter RJ made me aware of riving knifes, crown guards, short fences and proper extension supports which I adhere to and added with what I had and scrap. 


I am familiar with the clearance from the front (and up and over) of a true riving knife to the back of blade. My splitter does have about 1" gap there currently in the 6/4 position which I use a lot. It narrows as 8/4.. 10/4.. and 12/4 gets the call. But... I can remedy that simply with a small modification in about 30 minutes and I may go down and do it now as I have it on my agenda along with a million other things. And I can do it so the top of the saw teeth actually sit inside the crown guard and ride un-obstructed.


I have a Uni-saw that I could afford and it is as safe as safe can be without going to power feed. And it was not by a miracle of God or Delta Machinery that it got that way as that is not how it arrived in my shop on a crate. ha.. ha... ha... ha..ha..ha..


BTW.. from what I've seen of that Scheppach.. pretty nice saw!


Regards...


Sarge.. the tinkerer

Sarge..

Woodworkers' Guild of Georgia

tinkerer2's picture

(post #100906, reply #33 of 64)

"Sarge.. the tinkerer"


But Sarge,  I thought I was the tinkerer.  Ha Ha!  I started out being Tinkerer but when we had that change of the forum a couple years ago, I lost that status and finally became Tinkerer 2 to get back in the forum.


Paul

SARGEgrinder47's picture

(post #100906, reply #34 of 64)

Evening Paul...


You may hide under that tinkerer2 handle in an attempt to be formal, but you are and will always be "Tink" to me. ha.. ha...


I used to post under just SARGE before the change, but it got taken also so what you see is what ya gonna get I suppose.


Regards...


Sarge.. john thompson


Edited 7/24/2007 12:02 am ET by SARGEgrinder47

Sarge..

Woodworkers' Guild of Georgia

tinkerer2's picture

(post #100906, reply #37 of 64)

"You are and always will be "Tink" to me."


Tink, I like that.  Someone, some time ago, referred to me by that name and I always liked that.  By the way, what does "SARGEgrinder" come from?  I see you sing "john thompson."  Now that name sounds kinda Swedish.


Your humor and your keen evaluation of machinery always hit a special spot.

SARGEgrinder47's picture

(post #100906, reply #38 of 64)

Morning Tink..


After SARGE was taken during my absense and stay at the local convent during the Taunton switch-over, I had to add to SARGE with something. Grinder was a name given to me with my style of poker play as I prefer to take a nibble of the cheese and run rather than go for the larger chunk and increase the risk of getting caught in the trap.


47 is nothing more than date of birth. Not sure about any tie to Sweden? But just in case I am declaring it was obviously "southern" Sweden they came from. ha.. ha... ha..ha..ha..


Regards...


Sarge.. john thompson


Edited 7/26/2007 12:28 am ET by SARGEgrinder47

Sarge..

Woodworkers' Guild of Georgia

blackbird's picture

(post #100906, reply #64 of 64)

While I respect all the views here I think Sarge sums up the whole issue regarding safety.


Safety has to rest with the user, and unfortunately safety does not appear to be cool or trendy.


Originally from the UK, but living in Canada for the last twenty seven years I don't suppose the European designs would have much impact on safety when I see almost all users remove the safety guards on North American or European tools as soon as they attempt a task that the safety equipment causes slight inconvenience.


Safety appears to be low on most peoples priority list - until after the accident, and even then some people assume it wont happen twice and continue as before.


As a student in the UK I was taken to an industrial accident wax works museum where actual accidents are remodeled as they happened in all the gory details, the severed hands, injured eyes and torn off scalps due to long hair and drill press use without the guard, thirty five years later I remember that day and the wax models of the people in it.


Tradition is another reason we have the tools we do, they are familiar old friends and we like them, like the ones we used at school and the ones our fathers had.


Price of the tools also determines availability, and we have far higher availability than our European friends do, are we prepared to have less to be safer?


Manufactures are building what they believe we want, when we start wanting something else than we currently have I am sure they will build it, until then we could all try using the safety features we all have right now.


Sorry this is lengthy but on a closing note; I don't believe any industry world wide cares about safety at all but they do care about insurance costs, stock value and public image.


Safety is up to us.


Blackbird

highfigh's picture

(post #100906, reply #13 of 64)

From your comments, I'll assume that you haven't read the many threads on table saws, safety for TS, Saw Stop vs everything else, European saws vs American saws, etc. This isn't a new topic and nobody is impressed with the half-assed splitter/guard that comes on saws.

Yes, the dollar wins out again. No, not everyone will jump up and replace what they have. No, the companies don't have any mandates that require them to build their saws with a riving knife and they aren't willing to be proactive in designing new saws when they can continue to sell the same ones that have been their bread and butter.

We, as buyers and users of machinery and tools with cutters, knives and rotating blades, must accept a certain amount of the responsibility for what happens when we use these machines and tools. We can't just claim that the manufacturer didn't do enough when we are injured by being distracted, clumsy, ignorant of safe habits and inattentive. I narfed my left index finger with my brand new, shiny T&G router bit. It was my fault. I screwed up. I accept that. I didn't make any claims against the router or bit manufacturer, nor will I. We choose to use these machines and tools. It's up to us to use them safely. We should want the manufacturers to make them as safe as possible but we do need to be dilligent.

Maybe we could have a class action suit based on the fact that the supplied splitter/guard is such crap, that everyone removes them and makes their saw inherently more dangerous.

No, better not- the only ones who will make any money are the lawyers.
"I cut this piece four times and it's still too short."


Edited 7/21/2007 10:13 am by highfigh

"I cut this piece four times and it's still too short."
SgianDubh's picture

(post #100906, reply #14 of 64)

You are correct highfigh. Bob has brought up an old topic that's been going around on this and other forums for years- a decade or more that I know of. And of course you are correct to say that users of powerful machinery have a responsibility for their own safety. That self responsibility won't ever change.


I remember getting involved in those saw safety discussions here away back in the late 1990's, and on one or two other forums. I find it interesting that after all this time there are hesitant moves on the part of American saw suppliers to incorporate a riving knife on their machines. Some of these suppliers, like Bosch are European based, so they shouldn't have much trouble with European style machinery. And DeWalt has a history of owning Elu, another European company that Black and Decker swallowed up. So again, another business fully au fait with European regs and standards. 


I also find it interesting that the change in the stance on table saw safety in the US has been like watching a super tanker the size of the earth change direction, ha, ha. After all, just how hard can it be for a decent engineer to study the rise and fall mechanisms that  are normal on European saws that have been standard for decades, and come up with something similar? So, it's definitely not the engineering nous then.


The change is coming from some other angle, and who knows what that might be. Health and safety issues? Pressure from the buying public?


The saw safety topic's certainly not new as you say, but there again I can't recall seeing a topic truly new to me raised on a woodworking forum for many a year now. The old questions mostly just go round and round, and what makes the old topics interesting to me is perhaps a wee wrinkle in the question, or a bit of personality in either the questioner or in the posters that respond.


I guess it just shows how many people are either new to woodworking, or woodworker's with some to long experience that are new to woodworking forums in general, or perhaps new to this woodworking forum in particular. I've probably missed a category or two there, but that'll have to do for now. Slainte. 


KiddervilleAcres's picture

(post #100906, reply #32 of 64)

highfigh & ALL,


This isn't a new topic and nobody is impressed with the half-assed splitter/guard that comes on saws.


My point exactly.  We have been forced/expected to rely on these poor excuses for safety devices that in my opinion are border line insanity at best.  To the point of most users completely removing them, thus making the TS even more dangerous!


In the manuals, at least in mine, it says that under all circumstances the user should/must have the splitter/guard installed. And then they have the audacity to provide a device that could never have been tested or they would have found that it doesn't line up with the blade and is so flimsy that it actually makes the TS more dangerous. 


The board gets caught on the splitter unless you bend the arm to align it with the blade.  You see pictures that say, "Splitter/guard removed for clarity" or some such nonsense when the reality is, "Splitter/guard removed cause it's useless!"


Now they are mandated to provide a riving knife that's been available on Euro saws for nearly a ¼ of a century! HELLO!


Perhaps we should give Mr. G a standing O.


Regards,


P.S.  Yes, I did take a dunk in the lake this past weekend!


 


 


 


Bob @ Kidderville Acres


 


A Woodworkers mind should be the sharpest tool in the shop!

Bob @ Kidderville Acres

A Woodworkers mind should be the sharpest tool in the shop!

brownman's picture

(post #100906, reply #30 of 64)

I just read and responded to the following thread on the PM2000 saw, but it's worth repeating here. It appears from the owners of these saws that Powermatic has left off their braking type motor, which in my opinion is very much a safety feature. Doesn't it seem kind of ironic that they would add a riving knife, then leave out a braking type motor? Once again the almighty profit's of capitalism are still very much a motivating factor at the expense of our safety. Go figure!
Danny

SteveSchoene's picture

(post #100906, reply #3 of 64)

Newly designed saws are going to be required to have riving knives quite soon in order to be UL listed.  There is a longer phase in period before older designs have to be redesigned or replaced in the model lines.  Since long experience has shown that safety doesn't sell there hasn't been a competitive reason to change the long standing designs that work well in other respects, and which are quite safe if the existing safety devises, splitters, hold downs and blade guards, are used.  Riving knives make it a lot easier to use the devise with fewer reasons to remove for particular cuts.     

Test your finish on scrap, FIRST, or risk having to scrap your finish.

KiddervilleAcres's picture

(post #100906, reply #4 of 64)

Steve,


You have always had my respect.  If you don't mind I will respond:


Since long experience has shown that safety doesn't sell there hasn't been a competitive reason to change the long standing designs that work well in other respects,  


Wow,  The bean counters strike again?


and which are quite safe if the existing safety devises, splitters, hold downs and blade guards, are used.  What safety devises?  The ones we woodworkers devise to make up for the manufacturers shortcomings; such as crosscut sleds, zero clearance inserts, dowel pins behind the blade to act as splitters?  I get quesy thinking about those pins longevity.


Riving knives make it a lot easier to use the devise with fewer reasons to remove for particular cuts.  


My point, exactly!


Please don't take me as critical to your words.  Maybe I should get off this rant and go up to the lake and dunk myself in the water to cool down!


In my mind a riving knife in and of itself should be an integral part of a tablesaw.


Regards, 



Bob @ Kidderville Acres


 


A Woodworkers mind should be the sharpest tool in the shop!


Edited 7/20/2007 10:58 pm ET by KiddervilleAcres


Edited 7/20/2007 11:01 pm ET by KiddervilleAcres

Bob @ Kidderville Acres

A Woodworkers mind should be the sharpest tool in the shop!

SteveSchoene's picture

(post #100906, reply #7 of 64)

How else can a company respond, in a (mostly) market economy?  Companies that don't consider what sells go out of business, or find themselves relegated to small niche markets like Saw Stop. "Bean counting" isn't an option, it is vital, for companies that must make a profit to survive. 


Yes, I think the riving knive is a good feature, but good as it is it will only arrive because there is an agreement among all the manufacturers (given the UL consensus rule making process, I think that is pretty close to being right) to require them.  Any manufacturer trying to go it alone incurs extra costs that are not likely to sell many more saws and puts itself at financial risk.  It's a very expensive thing to completely redesign and retool. Requiring everyone to do it levels the playing field, at least among companies that have the resources to create new designs instead of copy patent expired machines.   


But, now that the UL rule is in place we can expect just about every new table saw introduction to come with a riving knife. 


You don't have to make a thing to operate safely.  Beisemeyer splitters work well even if they aren't quite as close to the blade.  Good blade guards are in the market to buy--Brett is one.  You can buy all sorts of devises.  Mostly the riving knife adds convenience for the user it's not the only way to skin that cat.  The fact that most don't chose to spend the money just illustrates the proposition that safety doesn't sell. 

Test your finish on scrap, FIRST, or risk having to scrap your finish.

HowardAcheson's picture

(post #100906, reply #20 of 64)

>> But, now that the UL rule is in place we can expect just about every new table saw introduction to come with a riving knife.

What I don't understand is how a saw with a european style riving knife is going to work when a dado or moulding cutter is installed. Dados have been outlawed in Europe for a number of years. The arbor on the saw is only long enough to install a blade.

If the riving knife is easily removed, then it will be no more useful than the blade guards currently supplied with table saws.

Howie.........
Howie.........
SteveSchoene's picture

(post #100906, reply #22 of 64)

I do think there will be a big difference in that there will be a lot less need to remove the riving knive for other cuts.  Splitters have to be removed for any non-through cut, including cut-off tables, while the riving knife doesn't.  But, you are right about having to remove them for dados and moulding head cutters, unless there is some sort of "adjustment" that keeps them in place while a smaller diameter cutter is employed. 


Blade guards currently supplied with saws are pretty disasterous.  I wonder where the one originally supplied with my Unisaw is?  Probably in its second or third reincarnation as a automobile fender, since it was likely replaced with a Brett when they became available.  


But I do use my Beisemeyer splitter, especially since it is quite easy to install. 

Test your finish on scrap, FIRST, or risk having to scrap your finish.

Lataxe's picture

(post #100906, reply #24 of 64)

Steve and Howard,


I can imagine (for I do not have one to actually test) that if the dado cutter's right-hand blade remains in line with the right-hand edge of the riving knife (as you would expect if the dado blade abuts to arbour flange in the same way as an ordinary blade) then the riving knife can stay on; and it will keep the workpiece in line with the fence. 


If the fence is also on the right, the workpiece will have the area of the workpiece that is to the right of the dado groove wedged between the fence and the riving knife.  The workpiece cannot move left (the riving knife stops agin' the wall of the dado) nor right (the fence stops it).  It matters not that there is no riving knife in line with the left-hand wall of the dado groove.


Of course, this assumes a riving knife that lies below the height of the blade, so the dado groove can pass over it.  Mine is a subsatntial riving knife that is always below the height of the blade (moving with it) despite having enough meat to attach the large blade guard. I can make cuts over the top of the blade with the riving knife in place (indeed I would not dare to do so without it). This is not unusual in European TS.


I don't know about dado cutters (banned in Europe - dangerous you know) but I assume they are the same diameter as a normal sawblade (eg 10 inches)?  If so, the above scenario should work.


Not so with groovers, I suppose, as the wall of the groove will be profiled and so interfere with the riving knife.....?


I am sure you will correct me if I have made a wrong assumption or drawn an illogical conclusion.


Lataxe

QCInspector's picture

(post #100906, reply #25 of 64)

"I assume they are the same diameter as a normal sawblade (eg 10 inches)"
"I am sure you will correct me if I have made a wrong assumption or drawn an illogical conclusion."

Most dado blades are 6" or 8" in diameter for use on 10" saws. Probably more to do with the mass of the rotating blades and the ability of the arbors and bearings to handle them. As well as the fact that they are not intended to cut through the wood, just groove it. That said I do have a 10" set and your comments about the riving knife with it would apply.

Dadoing on the wild side.

CarvinChris's picture

(post #100906, reply #26 of 64)

Wow, I've been reading this thread and what you fine folks have wrote about TS safety, here I'm fixin to upgrade from my little 10" portable to a 35 yr old Sears Craftsman 3hp that has none of anything mentioned.  The guy only wants $100 and the saw does purr like a kitten.  But caution will rule the day that I get it and put it to work.


Chris.

forestgirl's picture

(post #100906, reply #39 of 64)

Chris, you can add a splitter and blade guard to that saw, and (IMHO) you should.  You can make a wedge or pin splitter that inserts into a shop-made throat insert.  You an buy an overhead blade guard, or make one yourself.  Representative links below.....


Shop-made overhead blade guard


Penn State overhead blade guard


One splitter and a plan for a similar one
Another splitter
And a commercial aftermarket splitter


Although the splitter is rather insignificant looking, it is arguably the more important of the two devices in terms of the preventative protection it provides, but personally I won't work without either of them.  You'll find plenty of die-hards who poo-poo the use of these safety devices, if you want to you can let them convince you otherwise.


forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

CarvinChris's picture

(post #100906, reply #40 of 64)

Heyyy,


Thank you for the info, very interesting.


Chris.

forestgirl's picture

(post #100906, reply #41 of 64)

Any time, Chris.  Here's one of the entertaining things that can happen when things don't go well on a table saw.  In this particular instance, there was a splitter installed, but the stock was too small and not being fed right (by your's truly).  But lack of a splitter can create a similar problem, and of course the more prevalent stock-closing-on-blade thing.


  You don't want your hand following the stock, for sure!



forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

CarvinChris's picture

(post #100906, reply #42 of 64)

Nice burn-out ya did there...glad you did not get hurt.


My little portable has the splitter, the gripper teeth and blade guard, they are nice things to have for sure.  I was musing in my post that everybody was talkin about all the new and different safety items that can be had for a TS, and here I am contemplating buying a 35 yr old saw that has none of the stuff...kinda along the lines of 'my how things change over time'. 


By reading the posts by our trusty ol' friend Sarge, I figured I could modify it to make it safe, if I wanted to.  I thank you again for the links you posted, I made a folder in favorites for them, when I have a spare moment I'll stick them in a file on my PC for later use.


I basically was thinkin of getting the saw for a dedicated dado machine, I'm just not sure I want to pay $100 for it.


Have a good day out there on the left coast,


Chris.

forestgirl's picture

(post #100906, reply #43 of 64)

"I basically was thinkin of getting the saw for a dedicated dado machine...."  A great idea, and easily worth $100 in saved time as long as you have room for it.  "I wanna new shop!" she cries.


Those "gripper teeth" are anti-kickback pawls.  Some guys don't like them, because occasionally they can fall between the stock and the splitter.  I tie mine up with a Acco binder clip if I think they might get in the way.


My step-son picked up an old Craftsman saw at the fundraiser where I got the little Inca a couple weeks ago.  His doesn't have the guard either, but I have a couple junked ones, one of which we're hoping will fit.


forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

hammer1's picture

(post #100906, reply #44 of 64)

The ole tell tale quarter round. Cross cutting with the fence? Take your eye off the fence and...Or have the fence too close on the outfeed end, or have a dado cut out in the fence where the piece may hang up. Technique and set up are just as important as any devices. Those kickbacks take to the air and will lift off small kerf splitters. They can shatter a guard or toss the splitter assembly. It's great to have some safety devices but they are easily defeated if technique is incorrect. The reason I say this is from watching many students who watch the blade and not the fence. It's one of those accidents that happens too frequently and can result in injury. Glad you were not hurt.

Beat it to fit / Paint it to match

Beat it to fit / Paint it to match