Chainsaw inertia brake

[ben lightfoot]

With it turned off and chain brake off drop the nose of the bar onto an old tyre as this should activate it and will cause less potential damage than if dropped on a piece of wood

[treequip]

For God sake don't do the inertia test with the saw running. The chainbrake test is to yank the throttle open and push the brake on - the chain should stop dead and not run on!

 

The inertia test is to ensure the brake comes on if the bar is impacted in any way - kicking back and hitting your head is one way....ouch

 

But the chain brake would have applied then the saw kicked? Always assuming you had both hands on it. Using your face to trigger an inertia brake is an occupation reserved for Darwin awards candidates

[treequip]

Its not. The chain break test is testing if the chain break works...that doesnt mean to see your hand will activate the chain break in the event of a kick back. The inertia should kick in with a kick back also.....unless I am misunderstanding it, but I don't think so.

 

 

The brake will work on inertia alone and shouldn’t need the operation of the chain brake handle, that’s why they are different tests

 

Which takes me back to the original point that makes this ……

 

It means that you should check the chain stops when you have a kick back from the saw.

Wrong, it’s not kick back, its inertia, that’s why they have different names.

[morten]

The brake will work on inertia alone and shouldn’t need the operation of the chain brake handle, that’s why they are different tests

 

Which takes me back to the original point that makes this ……

 

 

Wrong, it’s not kick back, its inertia, that’s why they have different names.

 

I am sorry to tell you, but you are WRONG, and repeating your opinions does not make them any more true.

 

The inertia test will verify, that the chain break engages in case of a kick-back, i.e. when the saw accelerates suddenly.

 

The Husky link you quoted earlier tells you how to do the inertia test. It doesn't tell you WHY you should do the test (to ensure chain brake stops the chain in case of a kick-back).

 

This Stihl link does explain it, though: STIHL Quickstop® Chain Stopping System - Chain Braking System | STIHL USA

 

The STIHL Quickstop® chain brake is designed to stop the rotation of the chain if activated by the operator’s hand or by inertia if the saw kicks back with sufficient force.

Edited January 28, 2013 by morten

[Stephen Blair]

I have never heard of this test , very interesting, shall do it tomorrow.

As for chain break test, I do it everytime I start a saw.

[Steve Bullman]

Thank you Morten...I had given up arguing the point

[morten]

But the chain brake would have applied then the saw kicked? Always assuming you had both hands on it. Using your face to trigger an inertia brake is an occupation reserved for Darwin awards candidates

 

That assumes your left hand is at the TOP of the wrap handle. Most of the time it isn't, when you are not limbing, so your left wrist will NOT engage the chain brake handle. That is why the inertia break will provide some degree of protection against kick-back.

[treequip]

I am sorry to tell you, but you are WRONG, and repeating your opinions does not make them any more true.

 

The inertia test will verify, that the chain break engages in case of a kick-back, i.e. when the saw accelerates suddenly.

 

The Husky link you quoted earlier tells you how to do the inertia test. It doesn't tell you WHY you should do the test (to ensure chain brake stops the chain in case of a kick-back).

 

 

OK tomorrow I will take my 390 and swing it as fast as I can under full revs and you can put your arm in its path.

 

The inertia brake operates when the saw impacts, that’s why the manufacturers test is an impact test

 

The inertia test alone is not sufficient because the connection between the chain brake band and the operation handle can be broken, that’s why both tests are needed and described in the manufacturer’s instructions, or do you think they are wrong as well???

[Steve Bullman]

The drop test is performed because its the only way to test the inertia....unless you think that you are quick enough to snap the saw upwards to mimic the amount of inertia a kick back would produce???

 

You need to read up about inertia so you understand it better. Then you won't need to resort to the little quips(scuse the pun) below when you are losing the argument

 

OK tomorrow I will take my 390 and swing it as fast as I can under full revs and you can put your arm in its path.

 

[Steve Bullman]

ps...if im proved wrong i'll apologise and send you a free t-shirt