OK so I’m stupid. I agree with you..
I removed my splitter because it was to wide for a thin kerf blade I was using to cut some 1/4 inch Jatoba Plywood. I was cutting a Hexagon..
Well, BIG mistake! This is the third time in my many years of using a TS that I have been hit with a hunk of wood from kickback.
I’m lucky it hit my head so it didden’t hurt anything inside me that I use often!.
For a year or two I have been seriously considering getting a Powermatic 2000 with the router lift (50 inch). Mainly because it is rated a very good saw and has a riving knife AND a lift for moving it.
I have a small shop and this is important to me.
I am happy with my current so called ‘junk saw’ but maybe getting a saw with a riving knife may keep me alive for a few more years!
With the splitter there are no options other than removing it or making a different width one. I could have done this but I gave away most of my metal working machines I had.
Now my real question. I have used saws with a riving knife but I never looked into it’s details in relation to the blade thickness.
If your TS has a riving knife I would assume you have to remove it for certain operations but what about using different thickness blades? My gut feel is I’d be back where I started!
I’m I right or wrong.
HELP, I need it!
Replies
"Am I right or wrong."
Yes and no. It depends on the saw manufacturer. Some offer different thickness riving knives to suit different thicknesses of saw blade plate. On the other hand there are saw users that make their own additional riving knife or two to suit their collection of blades. Slainte.
Richard Jones Furniture
Glad to hear that you weren't hurt.
Since the splitters that come on most saws are as cheesy as they are (flimsy, bendy, cra-ppy steel- call it what you want), why not get a piece of 1/8" steel and make a new one for thin kerf and a better one for regular kerf? Two bolts usually hold it on and if you have access to a machine shop with a surface grinder, the new ones will be a lot stronger and there will be less adjusting after they're on. A little smoothing and tapering to keep the wood from catching on the rear edge of the splitter/knife and maybe some paint or powder coat and it should last a lot longer than the POS that comes with it.
Did you have the fence in position when you cut the plywood? I don't know if I have just been lucky, careful or just did it the best way possible but I have made many cuts free-hand and nothing has kicked back at me. The only times I have had anything like kickback was when it pinched between the fence and blade. I will never free-hand small pieces and I won't do it if anyone could come into the garage. I'm not telling you to free-hand anything but feed rate and pinching are the things that come to my mind when I hear about kickback.
A jig attached to a crosscut sled would make cutting polygons easy, if you find that you need to repeat this.
"I cut this piece four times and it's still too short."
Edited 9/23/2007 1:29 pm by highfigh
Making freehand cuts on the tablesaw? Wow, I think that's a bad idea. For Will George: I have used tablesaws for about 25 years with no kickbacks. I do use the "POS" splitter and blade guard that comes with the saw. I think that John White, the shop manager at Taunton, is a good source of information regarding tablesaw usage.That said, here's my take:Now you were using a thin kerf blade to cut quarter inch plywood - I don't really get that, but I think the tablesaw is a good piece of equipment for cutting plywood. I have a Freud combo blade on mine (one of the ones with the red teflon coating) and I have the fence and scale adjusted in such a way that I can throw a 4 X 3 foot piece of plywood on the saw, cut it, safely, and the cut will be square to within less than 1/2 a degree and accurate in measurement to within 1/128th of an inch. There's little to no tearout. The fence is adjusted correctly so that the word "binding" doesn't come into play. The splitter works like its 'sposed to.My Dad was a shop teacher who taught me how to use the tablesaw. He's old and feeble now, but I think if he heard anything about freehand cuts on the tablesaw, even though I'm 46 years old (47 next week), he'd probably feel entitled to come take my saw away from me and not give it back for a couple years. That, or I might turn to a pillar of salt, or something.Take care, Ed
Cutting freehand isn't for crosscutting and it needs to be done with the blade raised, so the teeth are pulling downward, not toward the user. As I said, I'm not recommending that this be done unless the user feels safe and keeps their hands far enough from the blade that if the board does flip or is kicked, they can't go into the teeth. Paying attention to the pressure required to keep the cut line and blade aligned and proper foot position/balance are absolutely necessary. I was shown how to do this in my high school shop class and at a table saw technique demonstration.
"I cut this piece four times and it's still too short."
Well good luck and stay safe. Definitely not a technique for me. Take care, Ed
Now you were using a thin kerf blade to cut quarter inch plywood - I don't really get that..I was cutting the ply. Hexagons after cutting some Purpleheart trim for the project. I just did not bother to change the blade.Purpleheart tends to splinter and I find that a thin kerf blade helps preventing that. Seems to help... ???(47 next week)! Damn your a 'Whipper Snapper' as my grandpa use to say.. HAPPY BIRTHDAY!
I have a JESSEM slider on my saw. But I was not using it. I guess I should have!
I thought I saw a Jessem in one of your photos. If I had one, I would have used it. If I made repeated angle cuts like that, I would probably make a jig that holds the piece at the center and use a piece of scrap with parallel edges after laying the shape out on the wood I needed for the project. With a compass, protractor and straightedge, I'd be dangerous! Also, the fence wouldn't even be needed, other than for lining the cut so it's aligne4d to the blade.Oh, well, at least you didn't get dinged up too badly.
"I cut this piece four times and it's still too short."
I have an INCA tilting arbor table saw with rifing knife. I have never removed the blade for any cut (Forrest) BUT if I had a thinner kerf blade I would follow the advice of the INCA mfg. This table saw allows the end of the saw fence to be clamped anywhere forward or back. If the operator places the end of the fence just past the arbor, your cut will be made to exact width and without the chance of kickback.
I always use with the end of the fence at the rear of the saw like most conventional guys BUT the above info in valid and works.
Don
"I always use with the end of the fence at the rear of the saw like most conventional guys BUT the above info in valid and works."
Don, using the fence as you describe, fully extended, is conventional in North America.
Here in Europe such practices are considered unconventional and dangerous for rip cuts because they trap the dimensioned piece of wood between the fence and the upcutting rear teeth of the saw blade.
Regulations here insist that we set the front end of the fence 'short ' for ripping much as you described in the earlier part of your post. Slainte.Richard Jones Furniture
I have an INCA tilting arbor table saw with rifing knife..I have no idea what is being described. Is this a fence with a positional auxiliary 'stop block' or some kind of slider attached to it?I'm old and slow sometimes!
Sorry Will, Don and I were sidetracking somewhat as we got talking about the position of the rip fence-- set 'long' US style, or set 'short', European style. In the image you should be able to see how the fence is set 'short' for ripping.
This allows the wood on the right of the saw blade as seen from the infeed side to be free of the fence after the cut is made. This set-up is standard practice in the UK where the long rip fence is considered dangerous. It's considered dangerous because if the wood opens up after the cut a long rip fence forces the cut wood tight against the saw blade. A 'short' fence lets the wood go free. Slainte.
View ImageRichard Jones Furniture
I hzvae the PM2000 and the riving knife system is just one of the reasons I like it so much. Very easy to work with and they do offer riving knives (low profile and full-plate for the guard system) in both full and narrow kerf versions.
I have a review of this machine with more on the splitter arrangement at the link below if that would help.
http://www.newwoodworker.com/reviews/pm2000rvu.html
Tom Hintz
Because there is always more to learn!
Thank you. I reviewed that post yesterday but I guess I can't read..I'll have to read it again because as I remember it was stated the riving knife was a available. I read it as a option. Sorry, I tend to read things into written word that is not there or somehow get it mixed up with something from some place else.I went to the powermatic web page (at least I think it was theirs!) and the specification listed a riving knife so I guess it is standard.I also went to my local Rockler and Woodcraft stores this morning and looked at the PM2000 on display. I asked each about the riving knife and they never mentioned about different riving knifes being available and I wasen't smart enough to ask! LOL...I guess I'll just E-MAIL powermatic and ask!
One of the confusing points I am just becoming aware of is that the manufacturers call the splitter plate (that the blade guard and anti-kickback pawls mount to) a riving knife also. the lower one most of us think of as a riving knife is often refered to as a low profile riving knife by the manufacturers.
To my knowledge, the "low profile" riving knife is still an accessory with the PM2000. Of course, to my knowledge, my wife thinks I am cute and my Mother is sure I can do anything. Proceed with caution.Tom Hintz
Because there is always more to learn!
Will George, good for you for coming to your senses. Lends a whole new meaning to the phrase "Knocked up 'side the head with a 2x4" doesn't it?
While you're deciding on the PM2000, you could at least put a splitter pin in the insert of your current saw. Better than nothing. But get thee a good saw! Glad you weren't hurt.
Well, I was hurt but I'll live and I heal quickly so I'm lucky.Just doing a operation I do all the time and WHAM! I'm not sure what I did to cause it. I was reaching for the OFF Lever and I guess I turned the Hexagon. I was cutting some Jatoba Ply and it has a really 'slick' surface AND I keep my saw table waxed.. Yes.. I was using the fence for reference but I started the cut off of a 2 inch wide block clamped to it. I do this all the time.All in all, I guess that block should have been wider than the Hexagon I was cutting. Live? and Learn?But get thee a good saw!.. I LIKE MY RIDGID saw. It performs well on everything I want to do but I think it needs a NEW operator!!!
WG, I just noticed the "1/4 inch plywood" part of your post. Thin plywood is one of the most ornery of culprits. Might I recommend using a board clamped to your fence to provide a "channel" for the ply to ride in??
Also, if you are cutting "freehand" as a couple of people have assumed, I think there's a safer way to cut hexagons, which is essentially template-cutting on the table saw. If you'd like info about that, LMK, and I'll scan in some stuff for you.
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