I’ve been kicking this can down the road for years, but I finally got a job that involves cutting so much melamine board there’s no way I’m doing it with a circular saw.
I watched multiple safety videos before even opening the package, and now I’m just sitting here staring at it wondering whether I should fire it up and cut off a finger or two. I’m fucking terrified of this thing.
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Table saws are dangerous tools. Healthy caution and a big amount of respect is warranted. A circular saw of any type can maim you in ways doctors can’t fix, and the table saw by its nature is most likely to do so.
Do me a big personal favor and always wear your safety glasses and hearing protection. Believe you me, the fun stops when you’re halfway through ripping a board and your eyes reflexively shut because you got sawdust in them. Also: table saws never have anything interesting or useful to say. Don’t listen to them.
Okay that last part is me trying to be humorous, actually do listen to the saw, if you hear strange noises it can be indicative of problems. You can hear those through approved earmuffs or plugs.
Something I would do: practice hitting the off button. Get to know where it is, by feel. With your hand and your knee. You’re unlikely to put your fingers through the blade during an otherwise safe cut; it can happen, but that’s an intuitive problem. Push sticks solve that problem. I’ve cut myself on the push stick thousands of times with table saws. Doesn’t hurt at all. Push sticks are If you can touch the blade with your thumb and the fence with your pinky, use a push stick or push block. Also, get or make a featherboard and learn how to use it. Another useful device for keeping the fingies attached.
The unintuitive problem is kickbacks. Watch this video: https://www.youtube.com/watch?v=u7sRrC2Jpp4 If a piece of wood is trapped between the fence and the blade, and isn’t well constrained by the fence, it’ll pivot, dig into the back, rising edge of the blade, tension builds up, and then it gets thrown backward. If you’re holding onto that board when it kicks back, it can take your hand back through the blade with it. This is why they tell you not to use the fence and miter gauge together: The severed piece is now loose and unconstrained between the fence and the blade near the far edge of the blade, it almost certainly will kick back.
“Don’t crosscut with the rip fence.”I hate that phraseology, I’m gonna cross it out, because I’ve seen an injury caused by it. I enjoyed it a lot at the time because it was my high school bully that hurt himself, but I still learned this lesson: He was manufacturing rectangles of plywood 3.5 inches wide by 2 feet long. He ripped strips of plywood 3.5 inches wide, and then set the fence to 2 feet to cut them to length. I warned him to set up a stop block. He goes off on me about how it’s plywood, there’s no real grain direction so “crosscut” and “rip” don’t mean anything. I go back to what I was doing, not five minutes later I hear his saw strain, I hear a bang, I turn around to see him doubled over hugging a piece of plywood. It has nothing to do with the grain, it has to do with the shape. That same kickback could happen if you’re cutting acrylic, which is an amorphous solid.Don’t use the rip fence unless you have AT LEAST 12 inches of contact between the fence and the board/sheet. If you can’t do that, you may need to use a sled or a panel cutter instead of the fence.
Start out with basic operations, do a crosscut with the miter gauge, hold the board and the miter gauge with both hands, feed it gently. Then try some rips.
Oh, one final thing about ripping: The edge of the board or sheet that touches the fence must be rather straight, you don’t want to put an apprentice’s jigsaw job against the fence because the board might not be well constrained, it may pivot and kick back. There are ways to straighten that edge if needed, learn them.
Holy fuck. That intentional accident genuinely upset my stomach. I don’t think I know anything about table saw safety. I guess it’s good I don’t own one but at least now I know what the shark fin is for. I’ve had my fair share of incidents with chop saws, handheld circular saws, and chainsaw wheels but chop and table saws stills care me more than cutoff wheels.
It’s called a riving knife. Sounds like a Klingon wedding implement but it’s a massively important safety feature.
Based on the context in the video, it seems like people remove it. Why?
Well there’s lots of reasons why you might.
On my table saw, you have to remove the riving knife to install the blade guard and splitter. They plug into the same port.
You can get wide and narrow riving knives for my table saw to match wide or narrow blades.
On my table saw, the biggest reason I remove my riving knife and run it without is for dadoing. A standard saw blade is 10 inches in diameter, a dado stack is 8 inches in diameter. The riving knife is too tall. On my saw it has to come out for dado use, on others it retracts. It’s not hard to forget to reinstall/extend it.
Sometimes you’ll use a table saw with jigs or fixtures that would interfere with the riving knife, so you remove it. In those
You’ll also see folks remove it for use with a zero clearance insert. There’s a large hole in the table top that the blade comes out, it has to be fairly large so you can change the blade. Most of it is filled with a removable plate called the throat plate or table insert. PLastic or metal ones have fairly large gaps around the blade which can present a problem, thin offcuts might fall in there. So folks will make them out of wood, and simply raise the blade through it with the table saw running to cut the slot for the blade. Well the riving knife won’t cut its own hole. So you either have to do that some other way or do without.
Oh, it’s worth mentioning: Riving knives have only been required equipment on new table saws since 2003, in the US at least. A lot of table saws out there don’t have the provision to install one.
Ah, very interesting. At some point I’ll clear room and take my dad’s saw. That predates 2003 for sure, but I remember it having a flappy clear cover over the saw and two serrated tails to prevent material slide back (not sure if that’s also kickback). It mounts into where the riving knife would be and I assume it’s mount is, effectively, a riving knife itself. We never did fancy work though, just plywood shelf cutting (now replaced with a battery circular saw) and ripping 2x4s like idiots.
That blade guard almost certainly mounts to a splitter, which does pretty much the same job as a riving knife. The technical difference is a splitter is mounted to the table, a riving knife is mounted to the motor/blade assembly. Those serrated tails are called anti-kickback pawls, they are indeed meant to arrest a board (sheet, really) during a kickback by digging into the stock by digging into it.