KICKBACK - Page 2A - Kickback Variables
Type of Cut
....As noted earlier, ripping against the fence presents opportunities for a kickback. A fence leaning into the blade or a blade leaning towards the fence can force the back of the cut board into the rear teeth. A fence that isn't parallel to the blade from front to back can result in the same problem. The result can be the classic "spear chuckin'" kickback.
....Cross cutting, using the fence to postion the board and the miter gauge to hold it as it is fed to the blade, presents an opportunity for a "flippin' and flyin" kickback. If the cut off gets trapped between the spinning blade and the fence it can make contact with the teeth at the back of the blade which will lift it and throw it. BUT - worse yet, while doing that, it can also deform the blade into the board being cut. The animation below illustrates what can happen if that occurs. The "flippin' and flyin'" kickback is a scary one because the flying stock is on the left side of the blade - "the safe side" when ripping.
To minimize the likely hood of the "flippin' and flyin'" kickback look at the two diagrams below the animation and read the text. If you take the pecaution shown in the second diagram you will significiantly decrease having the "flippin'and flyin'" kickback happen to you. Worst case, it'll be the small cut off that goes flying and not the rest of the board.
....If you use the fence and miter gauge for cutting dados or rabbets, you run the risk of a "flippin' and flyin'" kickback. Using a stand off board clamped to the fence in front of the blade can signicantly reduce the risk.
USE THE SPLITTER OR BETTER YET A RIVING KNIFE!
(pointed out by MadMark - see links on the last page of kickback to get to his safety page)
....Small stock can be harder to control than large stock, especially towards the back of the blade where bad things can start to happen. Small pieces get thrown a lot faster than larger, more massive pieces.
....An unexpected stop during cutting can be distracting and cause you to lose control of the stock. Having an obstruction in the outfeed path of the cut stock means you have to stop and clear the path. Letting go of the stock to turn the saw off can be distracting and can result in losing control of the stock - not a good idea. BEFORE you start the saw, check the outfeed path and verify that it's clear. If you're using a roller stand, make sure it's set to the proper height - too high and it can stop your feeding of the stock or get knocked over by the stock and be totally ineffective. Too low and the stock being cut can be raised up into the horizontally spinning teeth as you finish the cut and that's just when you're hands and body are closest to the spinning blade.