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In multiple questions (this is one) having to do with sliding miter saws, we have been admonished how to correctly make cuts - to wit: with the motor off, pull the saw outward, push the saw down, turn on the motor, push the saw forward, turn off the motor. This is described as the safe way and even shows up in instructions provided by manufacturers.

Now, when I use my radial arm saw, I pretty much do the opposite, to wit: setup the cut, turn on the motor, pull the saw outward, push the saw back, turn off the motor. I think this is the safe way to do it - have made thousands of cuts without mishap and I'm sure it's the accepted procedure.

So my question is: why is the safe way to make the miter saw cut to push, and for the radial arm saw to pull?

In both cases the blade is turning the same direction and on both saws the cut board is against a fence.

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You are, indeed, using your radial arm saw correctly, but it's important to note the critical differences between the two tools.

In both cases, you would be making a climb cut when pulling the blade toward you. A climb cut is generally less safe because the blade literally tries to "climb" over the wood as it pulls itself into and over the wood. If you are not used to using a radial arm saw, it can be difficult to control and can pull itself toward you faster than you may expect, especially if the blade's teeth have a positive hook.

Using a blade with a negative hook angle makes a climb cut easier to control.

So my question is: why is the safe way to make the miter saw cut to push, and for the radial arm saw to pull?

Let's start with the second part of that question--simply put, it is impractical to use the radial arm saw any other way. First, you cannot easily raise the blade over the workpiece. Second, it pushes the workpiece down into the table. The blade's ability to climb over the workpiece is limited by the fact that the blade's height cannot be raised accidentally in the middle of a cut on a properly set up saw. To make a cut with a radial arm saw by pushing the blade instead of pulling it toward you, you would need to pull the blade toward you, position your workpiece behind it, and clamp the workpiece down (to prevent the saw from potentially lifting it off the table).

In contrast, a sliding miter saw does have the ability to raise the blade over your workpiece. However, it does not have any feature to lock its blade down at a fixed height, allowing it even more climbing ability if used to make a climb cut rather than following the recommended procedure.

  • In other words, they're used differently because they're designed differently, and the miter saw as been winning because, while it may be slightly less versatile, it is far more portable and arguably somewhat safer. – keshlam Jan 27 '16 at 14:47
  • This is a great answer. – Reactgular Jan 27 '16 at 16:40
  • Each edit has made your answer better. The essence is in the last paragraph. Any thoughts about why there is no locking feature on the blade height? – Ast Pace Jan 28 '16 at 6:28
  • Most Radial arms saws I have worked with have also had some sort of counterweighting setup to pull the blade towards the fence, so you literally have to work to pull it forward, and then if it encounters any interference, or the user looses grip, it will retract automatically. This safety feature becomes a hazard if you try to push through the cut instead of pulling. – Jacob Edmond Mar 30 '17 at 18:03
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I believe that the problem appears with the introduction of the sliding capability. If—in the cutting motion—the saw blade merely tilts, the forces onto the piece are always down/or to the fence, hence there is no force trying to lift the piece (on square cuts). Instead, when cutting a wide piece- as wide as allowed by the sliding stroke, and the saw is pushed back - the resulting force onto the piece might result being upwards which might be quite dangerous. For those reasons:

  1. The sliding motion is a limited fraction of the blade diameter

  2. The saw manufacturer ask you to always block down the piece

It's very clear that a sliding saw should be used in a pulling motion after it has been tilted in the rear position. At the end of the tilting stroke, a trigger stop should keep the saw at the dawn position, when the pulling motion begins, then the saw behavior should be identical to that of a radial arm saw.

The problem is that, for real safety you will need that that trigger stop, should additionally block the pulling motion if the saw didn't reach its lower position.

But it happens that this trigger stop has not (yet) been incorporated, hence by limiting the ratio sliding stroke to blade diameter a reasonable safety compromise has been reached. Beyond that, it is better to clamp the piece while pushing for cross cutting.

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