Replies

1. 
   SgianDubh | Aug 12, 2002 05:32pm | #1

   I don't think there's much to say really Kim, unless you're in the habit of using a regular US style saw left handed or something where you reach over the fence. Lock the sliding table, set the rip fence short to allow the timber to go free immediately the cut is finished, with the riving knife and crown guard installed correctly, stand to the left of the blade, right hand at the rear of the stock, left hand guiding the stock against the fence, and push away. When you get within about 450 mm or 14" of the blade, pick up your push stick or sticks as needed, set the birds mouth on the trailing edge(s), and complete the cut. (Note the different style of pushstick to the ones you're most likely used to seeing.) The image in the attached example of a Wadkin CP15 dimension saw in ripping mode should give you the idea-- This machine is rated at about nine horse power and it can rip about 130 mm (5"+) deep if the worker has the nerve, so there's no way will I (for example) use it to rip with a long set rip fence and without the riving knife and crown guard in place-- I imagine the Martin pumps out about the same HP or more, so ripping without the aforementioned guards is something only the inexperienced, lunatics and idiots will contemplate. These big sliding table saws are much, much more powerful than the Jet, Delta and Powermatic contractor or cabinet saws often talked about in woodworking magazines and in this and other forums, but the principles of operation are essentially the same.  

   One wrinkle; because the sliding table is set just a bo'hair higher than the fixed cast iron table-- to reduce or prevent friction during cross cutting operations-- there is an occasional tendency for the cut to be slightly off square, especially if you're ripping just a narrow edge off and where the stock width only just reaches the sliding table which can cant the piece a degree or so, so allow enough for a final light pass through your thicknesser to make sure the material is actually square.

   I don't know of any manuals, but if you'd like to pay my flight to NY for a weekend, hotel, fine wine and dining, visits to sleazy low-life boozers, perhaps a lap dancing entertainment centre, consultancy fees, etc.,  you could organise a seminar for a group of fellow new users, ha, ha-- I've been using this type of machine since the mid 1970's, and have some experience of instructing furniture making subjects, including table saw usage, which leads to even more ha' ha's! Slainte, RJ.

   PS. Aug 13. I did some editing to show the change in stance as the cut progresses from a 'sideways, left shoulder forward, standing to the left side of the blade' position at the beginning or middle of the rip cut to a more 'directly behind position' during the last 300- 400 mm where the push sticks are involved. I'm not sure if the images will load now, but if they do they should help illuminate the later discussion in this thread.

   View Image

   View Image
   

   
   

   ---

   Edited 8/13/2002 12:46:32 PM ET by Sgian Dubh

1. 
   MarkRoderick | Aug 12, 2002 07:14pm | #3

   How many amps does that 9hp motor draw?

1. 
   SgianDubh | Aug 12, 2002 08:00pm | #4

   Mark, I haven't got a clue. If I wrote down everything I know about electricity it would qualify as the worlds shortest book. That cr_ap drips out of the ceiling as far as I'm concerned. I was told by Wadkin when I purchased the machine that the motor is rated at 9 HP. So far I don't have any particular reason to doubt them.

   Another tip for Kim. You'll very quickly learn to double check that the previous user lowered and switched off the power to the scoring saw unit. Those spinning blades sitting a mm or two above the table top can give a very nasty cut. Slainte, RJ.RJFurniture

2. 
   SgianDubh | Aug 12, 2002 06:29pm | #2

   Another wee wrinkle that I've just remembered Kim, and I'll probably remember more later, but I have to go now and do some real work. When ripping just a sliver off a piece there is a tendency for the sliver to drop down between the edge of the sliding table and the left hand side of the blade which obstructs the path of the next piece to be ripped, and can be dangerous. With practice, you'll become adept at using the push stick in your left hand to flick the sliver away from the blade thus preventing this annoyance. If you've got a lot of pieces like this to rip, you'll soon think of a way to put a temporary false table of 6 mm (1/4") MDF the same length as the table and pushed through the blade just so far and clamped or double sided taped in place. This creates a substitute for a zero clearance insert in US style cabinet saws. Slainte, RJ.

   RJFurniture
3. 
   gweisenburge | Aug 12, 2002 11:11pm | #5

   Hi Kim,

   I've had a Felder KF700P for over a year now, and my machine looks to be configured similarly to the T-73 Basic (except mine is a dual function, saw/shaper). I believe your "outrigger" table and its fence are detachable from the slider. If that's so, I'd take them off and fold in the outrigger support when ripping. I then stand outside (left of) the the slider and about a foot behind the leading edge of the blade. That's about where I stood when ripping on my Unisaw. I think the position of the operator in Sgian's photo is standing in a particularly dangerous place (I could bore you with a near-horror story). I mounted a remote switch on the back end of the slider so its safer and easier to turn on and off the machine - especially when cutting sheetgoods.

   The difference between the Wadkins and the Martin, Altendorff, and Felder is that the last three sliders are right next to the blade. That being so, the operator can stand as close to the cutting operation as he needs. When ripping in half a sheet of plywood, I leave the outrigger on the slider (minus the crosscut fence), slide it back so its centered opposite the blade, and then position a roll-around table in front of and behind the saw (my tables are the same height as all my machines, with waxed Formica tops). I can rip sheets for hours without feeling in danger of either a kickback or that my hand is in way of the blade, because I set the blade only a quarter inch above the plywood (I don't have or want a scoring blade). I work alone and don't use guards or splitters on my 7.5hp machine, but I take few, however (for me) reasonable chances with safety. As the FWW disclaimer says, this business is inherently dangerous. If I'd been smarter when I purchased the machine, I'd have gotten the 9- or 10-foot slider and I'd be ripping my sheets more accurately and safely without a rip fence.

   My slider is in plane with, not even slightly proud of my waxed, cast iron table. I have not been at all concerned with the small amount of added friction when crosscutting. The factory sent the machine with the slider proud of the table, and I reset it in plane so I could cut a 90-degree rip on narrow pieces. When I'm ripping even a few pieces to 9-inches wide or less, I use a powerfeeder. Then my fingers aren't even close to the blade, and the cuts are cleaner without burning. I never thought of using a powerfeeder on a tablesaw, but its a real timesaver.

   Hope this helps,

   Gary

   PS - I hope you keep your tv from sending more reminders of 9/11 - I think especially you and the rest of us have have seen enough. 

   
   

   ---

   Edited 8/12/2002 4:15:52 PM ET by Gary Weisenburger

1. 
   SgianDubh | Aug 13, 2002 04:27am | #6

   Gary, that's the end of the cut as photographed. In fact, it's more than the end of the cut, it's well and truly after the cut. Body position changes from a sideways stance to a more direct behind stance as the cut progresses and inertia, timber weakness, and the push sticks come into play. It's hard to push the piece through those last couple of or three hundred millimetres unless you get behind the part. Kickback possibilities at the stage photographed are completely non-existent. To get kickback, a part of the timber has to be engaged with the sawblade, and in particular engaged with the rear rising teeth. I don't see any engagement of timber to blade at all in that image. Do you? Slainte, RJ.

   RJFurniture

   Edited 8/12/2002 9:33:43 PM ET by Sgian Dubh

2. 
   SgianDubh | Aug 13, 2002 06:41am | #7

   "The difference between the Wadkins and the Martin, Altendorff, and Felder is that the last three sliders are right next to the blade."

   Gary, as a matter of nitpicking interest, the Wadkin sliding table is right next to the blade too, as you can see if you look closely at the image I put up. You perhaps missed, or mis-read the comments I made on slivers getting trapped between the table and the left hand side of the blade in my earlier post which indicated that this must be the case otherwise I wouldn't have mentioned it. All the Wadkin dimension saws I've used had this pattern, but some of the earlier Wadkin saws that I haven't used, perhaps from the the 1940's and earlier were more like the modern Czech made Rojek. This style of dimension saw has part of the solid table extending to the left of the blade as viewed from the front and a throat plate much the same as US style cabinet saws. Slainte, RJ. RJFurniture

1. 
   gweisenburge | Aug 13, 2002 07:34am | #8

   Sgian,

   I'm sorry you took offence at my comments, but I stand by my judgement of the photograph. I can't tell if the operator moved at the end of the ripping process; I only see him (you?) standing directly in the line of fire. It looks to me that both those heavy pieces are still in contact with the trailing edge of the blade, and its rising teeth. Before reading your latest comment, I took the photo to the shop next door and asked, "what's wrong with this picture?" and we all four of us had a nervous laugh. 

   Sorry, but I'll tell that boring near-horror story now. An ex employee and his son were ripping 1 3/4 x 2 1/2 x 84-inch white oak stanchions (like studs) for a pilot house on a research boat. The kid was receiving and the father was feeding with a single, birds-mouth push stick. The piece, nearly through the saw, tipped on the edge of the outfeed table, and the son caught it, but tipped its end back down on the blade's trailing edge. Once the quite heavy piece got going, it traveled at a very high rate of speed the 60-foot length of the boat and 20-feet more before hitting a concrete block wall, losing only inches in altitude. There it punctured a football size hole in the hollow block. The projectile never touched a human, because I insist the area behind the saw be kept clear of people, and the machine operator was standing where I taught him to stand, to the side of the 3-hp Unisaw.

   We all took a very long coffee break and talked about what could have been a fatal accident. And we calculated the speed of the oak stanchion by measuring the distance between teeth marks on its trailing end, and factoring in the speed of the blade's cutting edge. Sorry, after fifteen years I've forgotten the answer, but it was VERY FAST. You do the math, I need only remember the hole in the wall. 

   I've seen the results of collisions between tablesaw launched wooden missiles and people (including myself, when I was a year into my career), and they aren't pretty sights. I therefore still believe the operator in your photo is in the most dangerous position when ripping.

   Gary

   Edited 8/13/2002 12:40:41 AM ET by Gary Weisenburger

1. 
   SgianDubh | Aug 13, 2002 10:34am | #9

   No offence was taken Gary, but there is nothing wrong with the stance seen in the image for the end of a cut. Read my first response to this topic again to see how the beginning of the cut is approached.

   I find this comment in your response interesting, "The piece, nearly through the saw, tipped on the edge of the outfeed table, and the son caught it, but tipped its end back down on the blade's trailing edge." Pray tell me how the material was forced down by the son into the rising rear teeth of the saw blade if the riving knife and crown guard were properly fitted? There's no need to answer, because I already know from your description that the machine was being used without any guards, and probably with a long set rip fence too to compound the problem. Now, if you and your staff would adopt safer work habits, i.e., fit the guards and use a short rip fence there'd be less need to approach ripping timber like a bunch of deformed contortionists in an effort to keep out of the way of all those projectiles. I'll extend the same offer to you as I did to Kim. Pay all my expenses and my consultancy fees and I'll fly to California to give you and all your nervously laughing friends lessons on 'safe' methods of table saw operation and practice. You'd be amazed how much less nerve racking the job is when some simple safety guidelines and practices are instituted. Slainte, RJ. RJFurniture

1. 
   gweisenburge | Aug 13, 2002 08:29pm | #10

   Sgian, I still maintain that there's never a time one should stand in the line of fire behind a tablesaw, planer/jointer, or any woodworking machine, as you maintain that the riving knife and crown guard should be in place. I can't argue with your safety logic, and when I got to my shop this AM I replaced the knife and guard on my Felder - maybe this old dog can learn a new (old) trick. Sorry, Sgian, I can't afford to bring you out to the Bay Area, and if I did, it'd be to booze it up with a lap dancer. 

   However, I've seen few, if any, safety devices used in the many professional and amateur shops I've visited, not that that makes it right. The guard and knife on my Felder, and perhaps your Wadkins, are simple to install, adjust, and remove when necessary, but safety devices on lesser machines are not that simple. After fighting the devices on my old Unisaw, I finally removed them. Then, after my own wooden missile accident (the scar in my forehead reminds me), I made a rule that no one should be behind the tablesaw blade. Whether or not I continue to use the crown guard and riving knife (I think I will), I'll keep the rule posted on the saw.

   As to retractible rip fences, I didn't know they existed, until I got the Felder. The unretractible Biesmeyer fence, a standard on Unisaws and Powermatics, is as long as the saw table is deep!  Now, when hand ripping on my Felder, I retract the fence end to the saw blade arbor. However, when ripping with my four wheel powerfeeder, centered over the blade, I must extend the fence just beyhond the last wheel. The feeder, as you might guess, provides the operator with the greatest safety when ripping - it covers the blade, holds down the workpiece, and the operator can easily feed the saw while standing off to the left. But this just points out that there isn't a hard and fast rule for rip fence position as there is with where an operator should stand.

   Come on, Sgian, I think you can agree:  whatever the saw, safety devices, or rip fence, there's no reason to defend standing in the line of fire.

   Gary 

   Edited 8/13/2002 1:33:13 PM ET by Gary Weisenburger

   Edited 8/13/2002 1:34:48 PM ET by Gary Weisenburger

2. 
   SgianDubh | Aug 14, 2002 11:41pm | #21

   Sorry for the slow response Gary. My modem died yesterday, but it seems to be fixed again today. I've been having a heap of computer trouble of late. I'll answer two of your questions in one post here.

   Q1. Strictly speaking I'd have to agree that keeping out of the line of fire during wood machining operations, e.g., ripping timber on a table saw, is the ideal. The only reasonably practical way I know how to do this in the operation under discussion is to use a power feeder. In the absence of a power feeder where hand feeding has to be done I'll defend my methodology to the hilt. As can be seen in the images in my first post the operator is off to the side for most of the cut, and using a stance that allows real motive power to be applied to the trailing end of the timber through the legs, torso and upper body. The worker only pivots a 1/4 turn anticlockwise for the last 200- 300mm of the cut to provide power to the push sticks. By this point of the cut the operator has a pretty shrewd idea whether or not the last 10" to 15" is going to be troublesome, and throughout the whole there's the riving knife and crown guard that add an extra measure of safety. I'd say this method of operation is preferable to any unbalanced awkward 'off to one side' stance that means the worker has to use his arms as long levers. In a related example, this time drawn from my sporting interests, If I have to push my weight in a rugby scrum, I get down low, bind on the forwards in front of me with my arms and drive forward with my legs. I don't stand off to one side with my arm sticking out, put my hand on the back of the scrum and lever my arm forward. It's weak and unbalanced.

   Q2. The sliding table can be moved further forward allowing the operator to stand further forward too, and sometimes this position is better when ripping lots of small light pieces. Slainte, RJ.RJFurniture

3. 
   gweisenburge | Aug 15, 2002 04:55am | #25

   Sgian,

   I appreciate your reply, because I think this is an important discussion about tablesaw safety. I'll try with words to explain how I rip sheet goods, but first I'll tell how I prepare. As I mentioned before, I roll in place an infeed table to support the workpiece before its supported by the tablesaw. I position the infeed table so the left edge of the sheet will hang off and is grabable. I then roll in place an outfeed table, behind the saw. Both slippery tabletops are tablesaw height. I also lock the slider, and position its outrigger table so its centered on the blade. With this system, I never have to support the weight of the piece to be cut, which is especially important when ripping 4x10 sheets of 3/4-inch, veneered, MDF. They weigh in at perhaps 120-pounds. Finally I set the blade height, with knife and euro guard, so there's about 1/8-inch clearance between the guard and the workpiece.

   Now, lets rip in half one of those 4x10 sheets, actually I'll do it alone, as I so often do. Let's say the front edge is the 4-ft-wide one that meets the blade first and the back edge is last to go through. I prepare by first positioning the sheet tight against the fence, with the font edge inches from the blade. I then stand in order to reach and grab the back edge of the sheet with my outstretched right hand. This hand will pull the sheet into the saw.  At the same time I grab and push against the sheet's left edge with my left hand near its center, about 5-feet from the back edge (ripping 4x8 sheets is so much easier). Then, while my right hand is pulling to feed, my left pushes the sheet both against the fence as well as applying some feed presssure. Steadily I feed the sheet, not walking, but sort of shuffling forward. While feeding, I'm also repositioning my left hand to always keep its angular pressure into the fence in a line (literally) that doesn't pass beyond the end of the fence. If I'm not careful, I could cause the workpiece to move away from the fence and bind against the blade (unsafe, and at least ruining the cutline). When ripping sheet goods, I prefer my fence extended to just beyond the blade's trailing edge. As the cut nears completion, with about a foot to go, I begin to reposition my right hand until I'm pushing against the back edge in the center of the soon-to-be 24-in-wide workpiece, between the blade and fence. My right hand is now also applying angular pressure against the fence as well as feeding, until the piece is well clear of the blade. When the cut is complete, the so called "fall down", the piece left of the blade, takes care of itself. Its out of harms way, but I use my now free left hand to move it further, while I use my right to push the workpiece also a few inches away. I now walk around and remove and set aside the fall down, and then do the same with the workpiece.

   You could criticize me for reaching across the blade, but now mine is covered with the euro crown guard (which I'm coming to like). I've never felt in harms way, and feel even less so now. Furthermore, I don't see how any pushing device can apply enough angular pressure to uniformly guide these heavy sheets through the cut. When I do it by hand this way, I must add that my movement is fluid and without starts and stops, which ruin the cut. 

   Ripping anything smaller is easier, and I use the same system, removing the outrigger table when the slider will fully support the fall down. I still do not ever stand behind the saw - I see no need to, and always stand about a foot or so to the left of and behind the blade. I did it this way with my Unisaw, and see no reason to change with the Felder.

   Whew, sorry for all those words.

   Gary

   Edited 8/14/2002 10:03:15 PM ET by Gary Weisenburger

   Edited 8/14/2002 10:05:19 PM ET by Gary Weisenburger

   Edited 8/14/2002 10:39:40 PM ET by Gary Weisenburger

4. 
   SgianDubh | Aug 15, 2002 06:02am | #27

   Gary, No criticism from me. Those big 4X8's, 4X10's, and 5X10's of MDF are tough to handle alone. I use a somewhat similar methodology for ripping panel goods. The only wrinkle I'll add is that I make the first cut two or three millimetres over the required width and go back for a final trim. Sheet goods like MDF aren't likely to cause kickback from pinching on the blade anyway because they don't have stresses to worry about, unless the riving knife or US style splitter are missing-- here the riving knife will prevent the piece being diverted back into the rising rear teeth of the blade after the cut. Big heavy full size sheets of MDF have a certain amount of inertia working in the operators favour- they weigh about 50 lbs. a cubic foot, with a 3/4" X 4' X 8' (2 cubic feet) piece weighing roughly 100 lbs. The crown guard has a perhaps unintended but useful secondary role in diverting chips and dust back down towards the table. Unguarded blades throw a lot of chips and dust into the operators face, causing distraction at least, and the greater likelihood of accidents. Even teeth broken off the blade can often be caught or diverted in their path by the crown guard and away from the operator.  Slainte, RJ.RJFurniture

5. 
   gweisenburge | Aug 15, 2002 06:49am | #28

   Sgian,

   In truth, I also alow an eighth of an inch and then rip that edge again should it come out less than perfect after the first cut. What I'm after is a jointable edge, either for edgebanding or a biscuit-joined, solid edge. I get that in about one out of three first-rips. If ever I upgrade to a longer slider, I understand that it can be used to rip as many pieces as one can stack on the slider, without using the rip fence. On the Felder, I think its possible to stack three, 3/4-inch sheets against the slider's crosscut fence and use it to rip all at once - leaving a perfect edge on all six resulting workpieces. The longer slider is desirable, because, as we all know, sheet goods aren't always manufactured with straight edges that'd yield a straight cut when ripped against a rip fence. Of course, a vertical panel saw would work equally as well, but I can't afford (the cost or space for) another machine.

   Gary

   Edited 8/14/2002 11:54:02 PM ET by Gary Weisenburger

6. 
   SgianDubh | Aug 15, 2002 07:37am | #29

   Gary, with a 3 metre (10 ft') sliding table and the locking devices often supplied as accessories (or home made locking devices) you can certainly straighten the edge of a 3M. long piece of timber pretty well, and certainly you can straighten those stable board material without recourse to a router/buzz saw and straight edge. Stack as many boards as you can on the sliding table up to the saw blades depth capacity and true all the edges in one go. European style sliding table saws and their slightly different methods of operation are a bit alien to most North Americans-- see RJT's comments earlier-- especially at the amateur and small professional workshop level where the cost of the European machines rather excludes many potentail buyers. These machines have been meat and drink to me for near enough 25 years.

   American style cabinet saws perform well out of the box for ripping to width, if kitted up with a decent fence and guards. And fitted with a  dado blade-- a tool I've never actually found a use for--- they're probably handy for doing grooves along the grain using the rip fence, and these machines rig up rather nicely for doing tenons off those favoured long fences. Their crosscutting capabilities are a bit limited, but you can manage to get by if the need arises. Slainte, RJ. RJFurniture

7. 
   gweisenburge | Aug 13, 2002 08:48pm | #11

   Questions:  can you move the outrigger table fore and aft on the Wadkins slider? If you can, would attaching it to the far end of the slider, and then moving the slider toward the outfeed end allow you to stand on the left of the slider?

   That's a neat outfeed table described in the photo's caption. Will you use an infeed table for support when ripping that stack of plywood behind you in the photo? My 1600-sf shop forces me to use movable tables for that purpose.

8. 
   DonaldCBrown | Aug 13, 2002 11:11pm | #12

   Gary and Sgian-

   Let me make an absolute statement and see what holes you guys can poke in it:

   A properly fitted riving knife and crown guard of the European design, together with a short rip fence, will in all cases prevent kickback when ripping, short of supernatural circumstances or unimaginable stupidity on the part of the operator.

   The short fence will prevent the stock being forced against the blade. The crown guard is fixed a few millimeters (1/8" or so) above the stock. In order for kickback to occur, the rising teeth of the blade must first lift the stock from the table, and only after that can a backward force throw the stock. The crown prevents the stock from rising, and the motor bill jam before kickback can occur.

   QED

   I await your comments.

9. 
   gweisenburge | Aug 14, 2002 03:10am | #13

   Donald,

   Although I haven't, until today, much experience with a properly installed riving knife and crown guard, I'd say your statement in bold may be incorrect. I can only imagine ripping a case hardened piece with internal stresses causing either or both pieces to bind against the blade, perhaps pushing the riving knife and the attached crown guard off to one side, and allowing the piece to engage with the teeth to kick it back. The European designed crown guard, attached to the top of my saw's riving knife, is about 3-inches behind the blades center, and I can imagine a workpiece pivoting the the guard up and away from protecting the top of the blade. Furthermore, I don't think the clear plastic guard would be any match for the saw's 14-inch rip blade driven by 7.5 horses. I'd guess there's a better than 99% chance the knife, guard, and shortened fence will prevent kickback, but I'd not want to bet my body parts against that albeit slim chance for disaster. I've learned about life not to say "never." For that reason, I keep all of me out of the line of fire - its easy to do so.

   I think that good workplace habits are what really protect me, and I don't rely solely on safety devices. I stand in a safe position, I feed either with a powerfeeder, a pushstick, or with my hands well away from the blade (as when ripping plywood). When working by hand in close, I glide at least one finger or knuckle along the fence in order to know, by feel, where my hand is in relation to the blade. My gramps, who taught me a lot about tools and life, often said, "Always know where your fingers are, because that'll keep you out of trouble in the workshop as well as when you're out on a date." And since I often use machines that belong to others, such as at job sites, I want my habits to always carry from one machine to the next, especially when using machines that don't have safety devices, or worse yet, with improperly installed ones. 

   There's a guy who stood nearly each day for forty years behind a Unisaw at a boat company in Sandusky, Ohio, pushing oak past an unguarded blade. He retired almost twenty years ago with ten fingers and a social security check, probably as a result of his good habits alone.

   Edited 8/13/2002 8:14:21 PM ET by Gary Weisenburger

   Edited 8/13/2002 8:14:50 PM ET by Gary Weisenburger

10. 
    Lilshaver | Aug 14, 2002 03:51am | #15

    I'd like to ask anyone, but perhaps especially Gary, how one stands to the side of a sheet of plywood or other wide stock and still manage to push it past the blade at the final part of the rip? I mean, isn't the operator way off to the side? He'd have to have really long arms! Or am I misinterpreting what you guys are saying and as Sgian shows in his second photo, the operator is allowed to move to the right to enable himself to actually reach the stock?

11. 
    gweisenburge | Aug 14, 2002 06:18am | #17

    jeff,

    My slider is about 12-inches wide, with its right edge very close to the blade. Attached to it is an outrigger table with a crosscut fence. The outrigger table is removable, leaving only the slider between me and the blade, the full depth of the saw. That's about the same as on my old Unisaw. I'm not "way off to the side," as you thought. I see in Sgian's second photo, that his Wadkin has a similar configuration, but his saw has a somewhat unique outrigger support that would get in my way (visible in the first photo he posted). Check out the Felder KF700P at http://www.felderusa.com/machines/KF700.htm. I think its more representative of other sliding tablesaws on the market, including the MiniMax, at one end of the cost spectrum, and the Altendorff, at the other end.

12. 
    DonaldCBrown | Aug 14, 2002 04:22am | #16

    Gary-

    Like you, I don't trust absolute statements about safety, and I highlighted my statement as absolute just to excite comment. Your thoughtful comments about workplace habits are correct. There is one statement I don't really understand:

    I can only imagine ripping a case hardened piece with internal stresses causing either or both pieces to bind against the blade, perhaps pushing the riving knife and the attached crown guard off to one side, and allowing the piece to engage with the teeth to kick it back.

    I have difficulty imagining case-hardened stock moving the crown guard the inch or so required to negate its anti-lifting properties. But, as you point out, safe workplace habits should allow for the most improbable of occurrences.

    If I may ask a follow-on question, Why on earth aren't woodworkers marching on the headquarters of Powermatic, Delta, General, et al. and demanding that rudimentary safety features such as adjustable rip fences, riving knives, and crown guards be standard equipment on North American table saws? You've mentioned kickback accidents from the merely hurtful to the tragic. Do you think any of them would have occurred if the saws had had properly installed Euro-style safety equipment, operator practice notwithstanding?

13. 
    gweisenburge | Aug 14, 2002 07:10am | #18

    Donald,

    I think your thoughts are right on, but I never marched on those manufacturers because until just a few years ago, I didn't know anything better was on the market. I suspect others have been in the dark just like me, because most woodworkers don't own saws as good as a Unisaw or Powermatic. There's really a lot of unsafe cr_p out there.

    The Unisaw's blade guard is really a contraption of way to many parts, and not only gets in the way, but only prevents fingers from wandering into the blade. It doesn't really prevent the workpiece from rising up and then coming back down on the blade. My euro crown guard has only four parts and does the job masterfully, but I'll continue to put my trust into safe work habits and not just  the guard.

    About the case hardened piece causing an accident:  that was just imagined, as I said, but I think most of us have had similar experiences with workpieces that "sproing" apart while being ripped. There's a lot of unpredictable forces working against safety there, and I frankly don't know if the properly setup safety devices we've been talking about will ALWAYS work.

    Finally, in answer to your last question, I think the tablesaw launched, 7-foot long, oak missile would never have left the silo if we'd had the euro crown guard in place when the father/son were doing the ripping. My own accident, getting clocked in the forehead, occured when I was trying to rip a very small piece - a really dumb, preventable accident which I'd give the crown guard a 50% chance of preventing. Could we prevent all such accidents with euro crown guard? I can't believe so, but there's no such thing as "operator practice notwithstanding." I repeat again that I think operator practice can prevent common, as well as very unusual accidents.

    Another personal example (I promise, it'll be my last):  I was standing to one side of a Maikita 15-inch planer while surfacing green oak for ribs in a small boat. The workpiece jambed and the machine literally disintegrated before my eyes - not into them, because, out of habit, I wasn't standing directly behind the infeed table. It was quite an embarassment for Makita, because all the safety devices were in place and not even the manufacturer could have predicted this strange accident. I got my money back, and then some, and bought a more substantial planer.

    Jeees, I forgot about Kim. I wonder if we all answered his original question about ripping on a sliding tablesaw.

14. 
    efarmer4 | Aug 14, 2002 08:29am | #19

    OK, what does "The European designed crown guard" and other fittings look like? Or how do they work different from the US stuff?? Any good web pictures or drawings that explain it?

    Thanks, Edward

15. 
    RSRose | Aug 14, 2002 10:42am | #20

    EFARMER4

    Here are some links which describe and illustrate pretty well

    http://www.hse.gov.uk/pubns/wis16.htm (scroll down)

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

    http://www.wsa.tas.gov.au/publications/pdfs/sapdf's/sa017s.pdf

    http://www.wood-workers.com/users/charlieb/X31.html

    http://www.herts.ac.uk/lis/ltdu/projects/mm2/start.html (go to the Circular Saw link - operation and setting up)

    Rich

    Edited 8/14/2002 3:46:07 AM ET by Rich Rose

    Edited 8/14/2002 3:55:08 AM ET by Rich Rose

16. 
    pritcharded | Aug 15, 2002 04:43am | #24

    Rich

    You have provided an excellent set of references. The Safety Alert from Workplace Standards Authority Tasmania is particularly informative.

    I live in Tasmania (a state of Australia) and as I alluded to above in an earlier post, accidents which occur here in one's workplace will bring you into direct contact with the WSA. As it turns out I've had first-hand experience of a formal interview with a WSA investigator and even though I was many levels of supervision removed from the accident (and in fact overseas at the time), believe me it's a situation I wouldn't want to find myself in again!  The act of parliament under which they operate has real teeth and only the seriously foolhardy would ignore their advice!

    Ted

    Edited 8/14/2002 9:48:31 PM ET by Ted

17. 
    RSRose | Aug 15, 2002 07:57am | #31

    Ted,

    I don't know how many times it has been repeated (apparently only to those willing to listen) that it is unbelievable that this technology has not been adopted by manufacturers selling into the North American market as a "better mousetrap" but that it is virtually unknown to the marketplace itself.

    There is nothing whatsoever high tech about this, it is simply straightforward, well designed engineering that meets the needs of the work. On seeing it for the first time, the universal response is, "Of course!"

    Rich

18. 
    pritcharded | Aug 15, 2002 11:12am | #32

    Rich

    Furthermore it's technology which has been around for a very long time. I got my first bench saw about 25 yrs ago and it had a European style riving knife and guard. Personally I wouldn't attempt to use my current 12" saw to rip without the riving knife being in place and the guard properly adjusted, but I guess "each to their own".

    Given the number of Unisaw style cabinet saws that must be in Nth America it's certainly very surprising that an after-market manufacturer hasn't see fit to produce a conversion.

    Ted

19. 
    DJK | Aug 15, 2002 04:26pm | #33

    I remember this discussion on the old site. For a good discussion about ripping on a slider, check Woodshop News August 1999. An article titled "Catching the rip with big sliders". Looks like Sagin's photos came from that piece.

    Dave Koury

20. 
    SgianDubh | Aug 16, 2002 03:14am | #34

    They did. I was the author. Slainte, RJ.RJFurniture

21. 
    efarmer4 | Aug 15, 2002 07:37am | #30

    AH! I see now! Thank you Rich! I can see now how the splitter/riving knife differs from the common US versions. Having it curve up over the back of the blade is a good idea. Anyone make a version that fits a unisaw?

    Edward

22. 
    pritcharded | Aug 14, 2002 03:33am | #14

    Don

    My machine has the setup that you describe and for what it's worth I've never had an "uncontained" kickback. However I have had contrary timber lift off the table and be restrained by the crown guard (at the start of the cut and not a problem as the guard was set to just clear the material being ripped). There have also been occasions when the timber being ripped has "closed" on the riving knife so severely that I've had to stop the machine and drive a chisel into the kerf to free it! Notwithstanding that my experience has been that the European style guards work well, personally I think it's simply good practice to not stand directly behind the timber when ripping on a bench saw.

    I'm not familiar with the occupational health and safety standards that apply in USA but in my part of the world if a person was injured or killed in a workplace as a consequence of a kickback on an unguarded machine, explaining the circumstances to the relatives would be the least of one's problems!!

    Ted

    Edited 8/13/2002 9:40:56 PM ET by Ted

23. 
    SgianDubh | Aug 14, 2002 11:45pm | #22

    "A properly fitted riving knife and crown guard of the European design, together with a short rip fence, will in all cases prevent kickback when ripping, short of supernatural circumstances or unimaginable stupidity on the part of the operator."

    Donald, I certainly don't agree with that. (You didn't expect me to I know.) The risk of kickback occuring can be reduced, but never eliminated. Slainte, RJ.RJFurniture

24. 
    SgianDubh | Aug 15, 2002 04:06am | #23

    Missed to answer that question on the infeed table there Gary. Yes, we do shove an infeed table about for handling large quantities of man made board. It's been in my mind to buy one of those ten boards at a time tilting, vertical to horizontal, foot pump height adjustable, panel handling carts from Häfele for about $450 plus shipping. I just need a juicily profitable job or two to invest in it. The draw leaf style outfeed table works very well, and best of all it's permanent with no dragging about needed. You can read about it, and how it's made, in old copy of Woodshop News, or in an old copy of Furniture & Cabinetmaking. The general pattern might be adaptable to your Felder, but I'm not sure. Slainte, RJ.

    RJFurniture

    Edited 8/14/2002 9:24:28 PM ET by Sgian Dubh

25. 
    gweisenburge | Aug 15, 2002 04:58am | #26

    Thanks, Sgian, for the infeed/outfeed table info, but I think I'll stick with my roll-around tables in my smallish, 1600-sf workspace. I use them for lunch counters, assembly tables, and to move finished stuff out to the flat bed truck.

    Gary

4. 
   SgianDubh | Aug 16, 2002 09:43am | #35

   RJT, white oak stained with strong green copperas (aka, ferrous sulphate which is a reactive stain[reacts with the tannin in the oak]) a thinned out light wash coat of lacquer to act as a barrier followed by grain filling with plaster of paris tinted with water soluble powder paint, and completed with two coats of sprayed pre-catalysed lacquer. Slainte, RJ.

   RJFurniture
5. 
   SgianDubh | Aug 21, 2002 07:43am | #36

   RJT, The Ferrous Sulphate reacts with the tannin in the (white) oak to give anything from a pale grey to an RAF blue depending on the strength mixed. In the example you were interested in the green copperas (aka Ferrous Sulphate) was a strong mix to act as a deep RAF blue background. Plaster of paris is an old method of grain filling much used prior to the advent of modern proprietary grain fillers available in a convenient can purchased at a polish supplier. The green you see is all in the plaster and intended to be a contrast and to highlight and showcase the open grain pattern of oak. I'd bet you could have some fun experimenting with the techniques involved. Typical in English Georgian furniture was the plan to fill the grain with colours that matched the background, so various 'brown' pigments were typically used to mix with the plaster. Matching or complementing the background dye or stain colour is still the most common treatment.

    Today we have water based powder paints in all sorts of colours that mix conveniently with plaster of paris, and it's quite easy to mix a bright colour with the white plaster or, if you prefer, a blending  colour. I chose a contrasting bright colour just for the fun and the hell of it. It's rather based on the oak liming or US termed 'pickling' process. I've never had a problem with the plaster of paris being brittle, but if you look at historical examples using the treatment you can sometimes see the white of the original 200+ year old plaster coming through. 

   For a full description of the techniques involved you might have to wait for the article to appear in a woodworking magazine, assuming the publisher in question accepts the manuscript.  The image below gives an idea of the result if anyone has dropped in and wondering what the hell RJT and I are rabbiting on about.  We certainly have got rather sidetracked from the topic of European style sliding table saws, ha, ha. Slainte, RJ. View Image

   RJFurniture
6. 
   SgianDubh | Aug 23, 2002 06:11am | #37

   Most likely Woodwork, out of Califruitcake, but I couldn't say even if they will, or when. They have become the publisher in the US that I have a good working relationship with, and I enjoy my end of the relationship. I just write whatever I feel like writing about and send it to them. They decide whether or not to use it, so maybe they'll find an edition in which it will work, or maybe not, ha, ha. Slainte, RJ.

   RJFurniture