Kickback intensity does it depend on the sharpness and/or size of the chainsaw?

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Length of bar and weight of saw effect it. A smaller saw will often kick back faster and harder than a larger saw, top handle saws are bad for it because even if using it with both hands your hands are very close together creating a pivot point and relying on the muscles in your wrist to resist the inertia
 
I would assume that a smaller bar on the same saw should in theory rotate faster then right? But if your hands are placed and everything else is identical I would wonder if the one with the larger bar has less rotating force. Also in your experience did the chain break engage and did that stop it fast enough if it did?
 
Kinetic energy release on a kickback. All of those factors would be at play. The potential energy stored in the mass of the moving chain and engine being released by the bite of the chain would create torque rotating around the axis of the saw. The sharpness of the chain would factor into the bite but the ultimate release would be tempered by the weight of the saw, bar and the chain having to overcome the inertia and resistance of gravity. Either way not something you want to be in front of.
 
Taking saw powerhead as pivot point,
nose/kickback as input force,
Longer bar would give same chain speed i'd think, but longer lever;
for higher concentration of forces into pivot/saw.
Would think same hub speed and size, same chain speed; perhaps more power per tooth engaged in wood on shorter bar?
.
Hand spread giving pivot and hold to saw in scenario as i read/ but would use bumper spikes;
as stated farther apart hands give more control/leverage.
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http://mytreelessons.com/rl/content/Hinging-Full.swf
 
Cut two times one from Husky 35 top handle saw abd one from Husky 266 24" bar both sharp very Sharp, both could have ripped my fingers off if they were anything but Sharp. Cut a pinky finger and index finger same hand left. Both times I was tired, one at the end of a long day and the other just as we were getting started in the morning driving about a new baby who is now 22 my number two Son.
Keep your saws Sharp and save the body parts,
 
I would assume that a smaller bar on the same saw should in theory rotate faster then right? But if your hands are placed and everything else is identical I would wonder if the one with the larger bar has less rotating force. Also in your experience did the chain break engage and did that stop it fast enough if it did?
I think the difference is weight and distance of travel with longer bars.
A 36" bar is about a pound heavier and a ft longer than a 24" therefore the longer bar would have a pound of extended weigh to carry one third more the distance.
That means in order for a 24" to kick 90° the tip would have to move a bit more than three ft. Basicaly the extra ft carrys a pound over 4.5 ft. Little saws will not kick as hard as a big saw because they don't have the inertia and power. It's not speed in my opinion as it stands right now but could bring forth an interesting discussion. The Top handle and little saws and little bars are more dangerous for reasons given on this thread. Not sure if this was mentioned but less respect is often given to smaller saws with hand grip and distance to body.

"The more she's 'tricked' the harder she kicks"
I find that to be true.
I remember having saftey meetings about the Simonized 372 about kick backs and that was with 33' bars. They did kick like a mule.
 
Length of bar and weight of saw effect it. A smaller saw will often kick back faster and harder than a larger saw, top handle saws are bad for it because even if using it with both hands your hands are very close together creating a pivot point and relying on the muscles in your wrist to resist the inertia
This all makes sense. I think it physically moves the saw more due to less weight/extended weight and possible a light grip. It moves move with less room for error.
 
Worst kickback I ever had was wide open in big wood chained buried past tip hit a pole barn nail the saw handle missed my groin but hit my pelvis and though no serious injury hurt like hell.
 
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