Check Your Blade Height

[LeftyTom]

I intended to cut a 1" shim (I know, mighty big for a shim) on the TS. All went well until the end of the cut. Then I got kickback, mashed my finger (not worthy of a pic), and broke my blade guard. :BangHead:

My error was the blade was set about 1/4" too low, from where I had made cuts earlier Tuesday.

Any suggestions for a replacement guard for a Jet 10" TS?

 

[Mike Davis]

I don't know anything about Jet, but I use a band saw for cutting shims. It's a lot safer for thin or narrow cuts and wedges.

 

[Glennbear]

Thanks for the reminder to check height. :icon_thum Now that I have one to use I echo Mike's thoughts on bandsaw usage. I am sorry for your incident but I am glad you had the guard in place, far too often they are removed for non through cuts and not put back :no:

 

[DavidF]

I have to say that I don't use a blade guard, but do use a push stick, a splitter and a feather board AND a great deal of caution! I set my blade to be a half tooth above the work piece. Sorry can't help on finding a new guard. Glad it wasn't too serious.

 

[Travis Porter]

I'm glad your injury was not more severe. As for a guard, you might want to check out shark guards.

I'm with Mike. I no longer make shims on the tablesaw. I got a shim "stuck" the last time I made one on the tablesaw and it ended up kicking the shim into my hand and I almost passed out it hit me so hard. This was over 15 years ago, but I have never forgotten it.

 

[CarvedTones]

Cannaworms!

I avoid using my TS and then usually use a jig if I can, but I find the argument for raising the blade pretty high to avoid kickback to be pretty logical. If the blade just barely clears the stock then the cutting teeth are coming in at an arc that has a lot of lateral force to it and more teeth are touching the wood at any given time to give it more "bite". If the blade is high, most of the force at the cut is downward and fewer teeth are involved. But there is significantly more steel in the airspace above the stock and the potential for a serious cut that could maim or kill you is higher. What to do? :dontknow:

 

[DavidF]

Cannaworms!

I avoid using my TS and then usually use a jig if I can, but I find the argument for raising the blade pretty high to avoid kickback to be pretty logical. If the blade just barely clears the stock then the cutting teeth are coming in at an arc that has a lot of lateral force to it and more teeth are touching the wood at any given time to give it more "bite". If the blade is high, most of the force at the cut is downward and fewer teeth are involved. But there is significantly more steel in the airspace above the stock and the potential for a serious cut that could maim or kill you is higher. What to do? :dontknow:

I had read the same thing and always had my blade up high and with a saw guard that is probably the way to go, but with the guard removed then I like to see as little blade above the wood as possible!

 

[CarvedTones]

I will hop back up on the fence again about the saw guard. I know this is partially due to having a low end model, but the guard and splitter are another source of mixed feelings. There is a little gremlin that lives in my saw; every time I power it on he pushes the splitter a tiny bit to one side or the other. At night he nibbles on the end of the blade guard so that it will catch on the end grain instead of smoothly sliding up on top of stock being pushed through. When he is really ornery he pushes the blade guard so hard it gets grazed. I don't tend to make the straightest cuts under these conditions; I pay so much attntion to the blade guard trying to catch a glimpse of the little devil that I sometimes let the board drift away from the fence a hair.

 

[LeftyTom]

Well, I found that the blade guard (only the plastic shroud) can be had from Jet for $15.95...plus $19 shipping .

I also found that I can remove that shroud, leaving me with an assembly that has a flat metal piece that extends forward 8", covering the top of the blade. Then there is the 1" lip that slopes down in front of the blade. That lip won't be in the way of most of the sawing I do, so I can work with that.

 

[Gotcha6]

Blade guard?

 

[Trent Mason]

I think I've almost injured myself more times when using a blade guard than when I've taken it off. For the same reasons Andy mentioned. I didn't even put it on my new TS and haven't had any problems. I don't run the blade up much higher than the piece I'm cutting though and always check the height before cutting. Sorry to hear about your bad experience.

 

[Gotcha6]

I guess I'm just 'old school' on this. I'd probably like to see guards on saws my children would use, but I learned a simple philosophy from a simple man many years ago. It concerned guns. He said he always kept his guns loaded. The theory was, if you assumed it was loaded, you would treat it as such, and be much more careful with it. If you were wrong, so what? But, if you kept it unloaded and you were wrong you could - and would - have a tragedy.
Same thing to me with blade guards. I tend to become complacent with these safety devices and in that I lose the respect necessary to operate the tool safely. Just MTCW.

 

[NCPete]

Tom, which JET do you have???? Installed the Merlin Splitter on my saw, and am not ever looking to reinstall the JET guard. If yours is the contractor style, perhaps mine will fit?

 

[Gofor]

Setting the blade high does nothing to prevent kickback unless you are using a splitter with anti-kickback dogs (and then only after the board is trapped by the dogs) or are using a featherboard. With the blade set high, the rear of the blade has the tendency to pick the board up and then follow the teeth around and launch it with tremendous force. This tendency can only be eliminated if the fence is absolutely straight and the board is fed straight. If, like many, someone uses the fence "kicked out" by a few thousands, the drop side can catch. If you wiggle the board, either side can catch.

Best to use additional kickback protection (ie featherboards, etc) and push blocks/jigs to keep hands away from blades, whether or not a guard is installed.

I have read on other forums of those who, like me, have the 110v saws and got complacent with sawing larger lumber without worrying about the kickback (weight of board and strength overpowers the saw and pops breaker, etc). Some who have upgraded to 3 hp+ or 12" saws found that they were in a new realm when it came to kick-back.

Please be careful, especially those that upgrade to higher hp. However, from what I have seen, most accidents occur with smaller pieces and thinner lumber, regardless of old pro or novice. (That is also especially true with miter saws).

Go

 

[CarvedTones]

Setting the blade high does nothing to prevent kickback unless you are using a splitter with anti-kickback dogs (and then only after the board is trapped by the dogs) or are using a featherboard. With the blade set high, the rear of the blade has the tendency to pick the board up and then follow the teeth around and launch it with tremendous force. This tendency can only be eliminated if the fence is absolutely straight and the board is fed straight. If, like many, someone uses the fence "kicked out" by a few thousands, the drop side can catch. If you wiggle the board, either side can catch.

I never wiggle the board, honest - but that little guy under the blade guard... :evil3:

I am not advocating ignoring safe practices, but I respectfully disagree with you about the board getting picked up on a little wiggle; it cuts and/or burns but the kerf constrains it too much for a tooth to get far enough out of the slot to get enough grip to lift the board unless it were a really light board that wasn't being held down at all. This is exactly how I get the not straight cuts I complained about earlier. If you get off the line the blade does bind a little, but most of the surface area in contact with the wood is just smooth steel on the face of the blade. There ae a few teeth, but they are mostly vertical and half are pushing up and half down with the ones pushing down getting a better bite as they are being fed fresh wood, not just abrely getting out of an open kerf by a few thou. If you lower the blade, far more teeth are in the wood and several are pushing in the same horizontal direction.

I really didn't think there was much question that a higher blade setting reduces the chance of kickback. It seems quite obvious that it does. The question is whether the tradeoff of having a greater risk of a very serious blade injury makes sense or not. I don't know.

I do agree that there are other ways to reduce kickback; it just seems that a lot of us have trouble using them and getting consitently accurate cuts.

 

[tom hintz]

I got into a bit of a confrontation with my publisher when some dink tech editor added a spot in my book about raising the blade high above the wood to prevent a kickback. Unfortunately, I totally disagreed, as did every saw manufacturer I talked to about it. To them, this is very simple. Kickbacks most often start at the back of the blade when the wood for whatever reson touches the blade and gets lifted. Raising the blade fully does put downward force at the front, but we now have almost straight up force at the back. Not a good plan if ANYTHING varies as the wood passes.
I have a story on my site abouut this very issue at the link below.

http://www.newwoodworker.com/bldhtkick.html

I went guardless for years like many others. Now, I use them whenever I can and have discovered it is not that tough, especially with a good guard system like that on my PM2000.

 

[CarvedTones]

Tom,

I think what is really hard about this is how little "real" data there is. I read your page and I agree about the additional danger of the raised blade. Then at the end you mentioned that you have had just one kickback in 30 years. I have had two in about 12 years. This doesn't mean I know more about kickbacks, but that I know less about properly tuning a saw and setting up a cut. One issue that hasn't been discussed much in this thread is hands and sticks. I usually use one hand at the fence away from the blade to hold the board down and against the fence, standing to the side of the saw on the fence side. This is why I have no issue with lifting. It burns and cuts off line and would probably lift if I didn't hold it down if thre is wiggle or kerf closing. The hand is usually my left hand initially pushing and then I switch to my right pulling later in the cut so that neither hand is ever very near the blade. I have a clamping sled for short pieces. I use the push stick near the blade pushing down and pulling toward the fence and the push stick is usually the source of any wiggle I get and to clear the off cut. I never stand in front of the saw. I have not had a kickback doing it this way. Both kickbacks occured with the guard and splitter on, blade low and worthless little pawls in contact with the wood. What factors contributed most?

 

[4yanks]

In 15 years of woodworking I have only had one (very minor) injury on the table saw. It indeed occured as a 1/4 ply drawer bottom was picked up by the back of the blade, then spun over the top of the blade and into my stomach. It felt like a very hard punch to the gut. I now always use a splitter.

 

[tom hintz]

Andy,

I really do agree that if things go perfectly, the actual blade height has little to do with much. However, it is when things don't quite go perfectly, which for all of us is pretty regular, a very small error or wiggle can grow to dangerous proportions with a bunch of blade exposed.
I never use a push stick but rather a push handle, and I use that all of the time unless I am cutting a very large piece of sheet stock. I hate the simple push stick, like the ones most saw manufacutrers include, because they provide virtually no directional control like a good push handle or rubber-soled push block will. Even so, a second or two of inattention and I am afraid a fully raidsed blade can instantly become a serious liability. I have heard from several guys who even with a splitter in place, had had a piece of wood flipped out. Thankfully, the splitter kept the wood from going across the blade where it seems the major power is generated but they did get whacked none the less. No big injuries other than bruises and one broken finger I am aware of.
I think this just shows us that regardless of having a splitter and guard in place, we can't go brain dead. We remain the most significant safety deveice around any woodworking machine.

 

[CarvedTones]

Tom,

I have a push block/shoe also and it does give me better control, but using it my hand will be much closer to the blade at some point than it will with a push stick, so I only use it on really wide cuts, which I don't often do. I use the plastic push sticks manufactured as push sticks. But I agree about the operator being crucial. If we use our numbers, which are too small for much accuracy, you are 5 times less likely to get a kickback than I am (you have averaged 1 in 30 years and I average 1 in 6). Actually, it's probably worse than that when hours on the machine are factored in. But I haven't had one in about 5 years; maybe I am learning. If you keep the wood straight and on the table, it won't kickback. If you keep your hands away from the blade you can't get cut. But stuff happens - someone comes in the door and you look up or there is some bizarre stress in the wood or whatever. I just wish I could get the same accuracy with guards in place. As I mentioned earlier, it is partly due to my low end equipment.