Chain shot question

[Randy88]

Was running my bell super t the last few days and all of the sudden I got to thinking about chain shot.   You guys know how it is, your focusing on what your doing and before long it becomes second nature and you just forget about anything but getting the job at hand done.    

I then noticed the bar guard on the front window, the bars run vertically, not horizontally and then after all the hours in it, I noticed the window, its just thin plexiglass, not bullet proof glass by any means.     

I've read a lot over the years about chain shot, never seen it firsthand though.      

So the question for the day is this, what should a guy do for a front window to help prevent chain shot, and how do you get away from being in the plane of travel of the chain in a bell when doing cut up type work.    When you pick up material and cut it up, you can only move a certain amount of distance and you usually end up in the line of fire of the chain in some way shape or form.        

My lower window has the grid guard on it, don't think I can even put a thicker window in it without doing major refab work to it.

Anyone familiar with the bells, want to offer some advice on this issue, doing felling work, it should be a non issue, but cut up work is a whole different ball game.    Thanks in advance for any insight.    

[Gearbox]

There should be a chain catcher just behind the sprocket . looks like a thread spool .

[gspren]

If the window really is just Plexiglas replace it with polycarbonate (Lexan), much more impact resistant. 

[chevytaHOE5674]

Get the thickest piece of polycarbonate in it possible. Chain shot is no joke, I saw a chunk of lexan windshield that was probably 1/2" thick with a piece of chain 99% of the way thru. You wont get a steel mesh fine enough to stop anything and still be able to see thru.

[Skeans1]

 

 We are required to all snow holes plated and to process to the side you're not looking at the bar tip besides the full lexan. Years ago a local guy was killed by chain shot here well processing in the brush.

[Randy88]

I'm not sure if you realize on a bell, there is no moving the head to the side, in order to pick up anything and cut it up, your looking at the bar tip or bar back, granted when its the bar tip, its cutting down and away from you.    

The polycarbonate, is that what's referred to as bullet proof glass?     Somewhere I have a sheet of 1/2 or 5/8 inch bullet proof glass, a 4x8 sheet that a business had left over when they shut down years back, is there any way to tell for sure that's actually what it is?

I believe the chain catcher is on it, I'd have to double check it, that is supposed to stop the whip action, but really won't stop any fragments from going out, or did I misunderstand that? 

I've read somewhere, there is a 15 degree arc from the sides of the chain, is that from anywhere along the bar length, or off the tip or back only?    

[Skeans1]

This shows the cone for chain shot but the biggest thing is don't have the bar tip pointing at your self ever.

Extremely long link fixed by admin

[gspren]

The polycarbonate, is that what's referred to as bullet proof glass?   

I'm retired from the Army Research Lab, weapons and materials directorate, and there is no such thing as "bullet proof glass" only bullet resistant glass and yes that's normally a form of polycarbonate, often a few layers laminated. Sometimes actual tempered glass was used in layers with the polycarbonate, try sawing into it with a normal hacksaw and if it cuts it's the poly and there should be some noticeable flex in a full sheet, if it's glass the hacksaw won't cut it. 

[Randy88]

For the time being, we're going to use the sheet of 5/8th inch thick we have found on hand, it cuts with a saw and have done some reading on bullet resistant material and will wait till next week and make some calls to see what they have to say about thicker material.   I know there's no such thing as 100 percent safe, its just not possible, anything can ricochet and bounce off anything.    From the reading I was doing online about accident reports where people were killed, if I understood them right, even plate steel is required to a certain thickness in order to be safe inside the cab.       One report claimed the best defense against chain shot was to throw the chains away after about five sharpening's and to never fix a harvester chain that's been broken even once.............armed with that info, I think I'll make up a batch of new chains and toss away all the old ones.

How come this has never really been mentioned with hand held saws, I get it that most have shields to protect the whipping action off the backside of the saw, but nothing off the front side??    When two or three guys are working in the same vicinity felling and limbing I'd hate to venture a guess how many times per day someone has a saw pointed or aimed at someone else, even if they are 50-100 feet away.   I get it hp plays a huge role in the equation along with chain speed, but still, are there incidents that didn't get reported or am I not looking in the wrong place for those reports?