DANGEROUS new trend in internet table saw videos? You decide…
a few viewers have asked me if this is safe this isn't a new question it's just the most recent example I've been asked many times if it's safe to cut or carve wood by passing it laterally across the top of a saw blade essentially cutting with the sides of the teeth some people see that and they automatically assume it's a sketchy or irresponsible way to use a table saw and I do have an opinion about this technique that may surprise you but first I have to be clear that a table saw is a dangerous tool and you assume some risk anytime you turn it on things can happen that we just don't expect which is why we use safety devices like blade guards and driving knives and safety glasses and push sticks and that's why as a general rule if something doesn't feel right to you you just shouldn't do it no matter what anyone on YouTube or anyone else says even myself of course that doesn't mean anything goes as long as you feel comfortable with it recently I saw someone trying to freehand cut a circle on a table saw he might have been comfortable with it but that doesn't make it any less Reckless the difference between Reckless and reasonable when it comes to assessing risk is best determined by asking yourself two questions what could go wrong and how can you protect yourself if it does now let's apply these questions to these techniques the first person I saw do this was Izzy Swan many years ago it's a process for turning dowels or Furniture Parts such as chair legs on a table saw because you can achieve a consistent size and shape on multiple pieces much faster and easier than an unskilled Turner could do with a regular lathe a very similar process can be used to turn Bulls on a table saw in fact I made a video about this some years back it works but to determine if the risk it poses is reasonable or Reckless we have to first ask what could go wrong now some folks believe that the saw blade was not designed to withstand pressure on the sides of the teeth and they worry that a tooth could break off and then become a projectile I don't agree with that assessment for one thing you aren't cutting with the full side of the tooth you're taking shallow cuts that only engage the top corner of each teeth and you're not applying that much pressure here I'm turning this bowl by hand I can feel how much pressure I'm putting on the blade and it's not that much I compare it to pressing as hard as I can with my thumb on the side of a tooth and there's no way I'm going to snap off a carbide tooth with that level of pressure think about what a saw blade goes through under normal cutting conditions each of these teeth hit the wood at about 140 miles per hour that's a massively hard collision and it happens over and over about 4 000 times every second sure when a tooth strikes the wood with its face under normal operations the steel of the blade is backing it up but the cutting is not really done with the face of the tooth as much as with the tip and those tips generally extend up above the steel blade plate and those 4 000 collisions with the wood per second are direct impacts during conventional cutting while it's only a side swiping action that occurs with the teeth when you're feeding the wood in a sideways or angled Direction of course the quality of your saw blade would be a factor I'm not sure I do this with a cheap blade of questionable quality but I wouldn't recommend making any cuts at all with a blade that's been poorly manufactured I like to see nice clean braising around each of the teeth on my saw blades the second thing that could potentially go wrong is the work piece could theoretically catch on the blade and possibly get away from you maybe if you're taking too deep of a cut and then it can become a projectile in itself in this case the work piece is held between two Center points one is sticking into each end and I do mean that literally there is a bolt driven deeply into each end of the wood work piece it would take a hammer and a fair amount of pounding to get that thing to break free I don't believe there is any danger of it coming loose while cutting on the table saw the bowl is held in place by hand now is that less safe well unless you've done it yourself it's difficult to describe how little effort it takes to hold and turn the bowl within the jig in fact I could take my hands off it completely and it's still not going to go anywhere incidentally this is a very similar process to what has been used to cut coves on the table saw for a hundred years or more wood is fed directly across the top of the blade either at an angle or sometimes directly perpendicular the rotational direction of the blade and The Jig that guides the work piece makes it virtually impossible for that work piece to be ejected the third potential problem with these techniques is the effect such lateral or pressure may have on the Saw's bearings are they able to withstand that much force again my response is that the force is pretty minimal if you have a very old saw with worn bearings then you probably shouldn't do anything that may add unneeded stress to them but a saw of decent quality and condition should hold up fine now those are the things that at least theoretically could go wrong and as much as I think they're unlikely to happen we still have to ask the second question if we're going to determine whether a technique is reckless or reasonable how can we protect ourselves should one of these things happen well the most obvious answer is to wear safety glasses in case something does fly back at you and most importantly be sure the jig itself keeps your hands away from the blade notice how her hands are positioned with lots of things between them and the blade while the Saw's blade guard had to be removed the jig itself becomes the guard if something goes wrong if she's startled or something breaks her hands are never over the blade or in its path likewise here there's an inch of hardwood between my hands and the blade and in this case The Jig itself makes it impossible to inadvertently get my hands too close in fact in both those bowl cutting cases the blade itself was fully covered during the entire process so I was even protected from a flying tooth so in my opinion these techniques are not reckless in fact they're relatively common and have been for Generations particularly cutting across the top of a saw blade to form a Cove you've just perhaps never seen them before but one question remains while these techniques may not be particularly unsafe are they the best way to do the job frankly if you have a lathe you're going to find it more enjoyable to make a bowl in the conventional way than with a table saw the same is true with Furniture legs but there are cases particularly when you need long straight cylinders or multiple copies of the same simple shape when a table saw jig can be useful now you want to see something else useful Rich carbide is the best kept secret in woodworking I kid you n