broken bands ejecting from saw

[muskoka guy]

After reading the manual for our new mx 34 Norwood bandmill front to back, I came away from it with the knowledge of how dangerous a broken blade can possibly be. As I am new to milling, I have yet to experience this. The manual states that the non operator side, where the sawdust ejects, must have a 50 ft safety zone when the mill is in motion and the blade is turning. It states 20 ft safety zone on the miller side. Basically the only safe place is behind the mill head at the operator position. I have been watching u tube videos of people cutting logs to try to get the best method for cutting. Some of the videos show people standing right beside the mill as it passes on the cut. Are these people in as much danger as the manual states. I have yet to break a blade, but I can picture hitting a nail or clothes line anchor or something and the blade shattering. What causes most broken blades. Is this as violent as I have it pictured in my mind. Does it cause damage to the machine or just the blade. I have an amatuer prospector type metal detector. Probably a good idea to use it if nails are suspected. Thanks

[POSTON WIDEHEAD]

I have never broken a blade by hitting metal. All the blade i beak have been due to it's end of life. I usually get a blade sharpened 8-10 times and that's if I have not hit metal during the life of the blade. My blades break during a cut and I've only had 1 break while out of a log. I've had a broke blade come out the sawdust chute and if someone had been standing there, it would have been possible they would have been injured.

Blades stretch, get stress cracks in them and when that break.....it scares the sap out of you.

I have a sign at my mill warning people to stay back. When a blade is turning that fast, if it hits something, there's no telling which way it may throw something.
I make people move way back when I mill. And who knows....sometimes accidents will happen that can't be explained.

Just do whatever it takes to be safe and keep others safe.

[catskillpond]

We have thrown a couple and broken 1 they do tare apart the plastic cover we riveted some 3/8 rubber inside to try to protect the cover but it still cuts through we are servicing ours for the season going to try to come up with another cover saw one guy on the road with a plywood one might go there

[BBTom]

I do not want to unscare you, as being scared of broken blades is one way to be safe. But on the other hand, I have broken hundreds of blades, and only one of them came out of the housing.  I do run a WM LT40 Super, so I cannot speak for other machines.  It is always prudent to stay safe.

[drobertson]

Never seen one escape the covers other than just around the blade guides, but a big narly mess still waits, safety first as usual, no need to stand in the path of the blade rotation regardless of which side one is standing.

[Jim_Rogers]

It can happen:



I don't want to scare you, or un-scare you either, but it took 12 years for the first blade to come out the sawdust chute.
But it can happen.

Jim Rogers

PS. I has happened to me at least twice.

[ladylake]

 

Jim  In 2.5 million bf thats the worst I've had on my mill almost exactly the same.  Good thing they put those metal fingers inside the chute to keep the band from flying out.  Steve

[cutterboy]

I think Norwood is covering itself from a liability standpoint by saying 50 feet on one side and 20 feet on the other. Don't worry about it. You will break a blade once in a while, and it will give you a start, but no one will get hurt.

Cutter

[ladylake]

 One other thing, the boards come off the chute side on my B20, I keep offbearers behind the head when sawing.  Steve

[hamish]

Don't use your hair dryer in the shower................................just covering there butts.  Sure it can happen, as to what extent, well mythbusters will have to get on the job.

Hand grenades have a lethal and danger zone, I still don't want to be one meter outside that danger zone.


Its pretty much common sense, same as you wouldn't mow your lawn and direct the discharge shoot towards your kids.

[beenthere]

Its pretty much common sense, same as you wouldn't mow your lawn and direct the discharge shoot towards your kids.

Right on, but sad to witness how often you see people doing just this. With people in the yard mowing away, back and forth.
I once turned around and went back to have a short talk with a guy who was mowing with a small lawn tractor while pulling his young son in a small wagon behind his tractor. Pitiful what could happen in a blink of an eye (or loss of the same). Some just do lack common sense.

[Ga Mtn Man]

The noise is what will really get you.  Sounds like a gun going off.  Not sure if the sound is from the blade breaking or the tension releasing in the saw head. Either way, it always makes me jump.

[thecfarm]

As was posted,it's to cover the saw maker. Not a bad idea to follow it,but I know hard at times too. I don't allow any one by the discharge. I'm more worried of a knot or a chip of wood MIGHT come out of the discharge. I myself am more concerned about that than a blade. BUT I'm not saying that won't happen either.

[Bibbyman]

Wood-Mizer has the best shielding I've seen.  But over the years we've had some dramatic blade breakage.



  

 

[fishpimp]

That's what I'm afraid of! Coming back toward the operator!
Yea I've looked thru my manual but what's the blade rpm of a wm lt40 series or similar ?

[Banjo picker]

Keep anything you value away from the discharge side of the mill....Mine has something like 1/2" or so bars on the discharge shoot, and one of them is bent from when a band broke when not in the wood....Just because it hasn't happened to one of these guys don't mean it won't....Be safe not sorry.  Banjo

[pineywoods]

The discharge chute on my mill connects to a sheet metal duct that's part of a sawdust extraction system. I've had pieces of a broken blade punch a hole completely through that sheet metal, twice. I had a bicycle speedometer hooked to one of the bandwheels. It shows the blade speed to be 55-60 mph..The real nasty scarey breaks are when the blade is up to speed, but not in the wood..

[WH_Conley]

I have broke hundreds of blades. '97 model LT40. I sharpen and use them til they break or get too narrow. I have had one completely exit the machine. Far end of the blade to the mill, 37 feet. Most just ball up, sometimes can be a real pain to get out. I allow no one in front or discharge side of mill when blade turning. I usually saw with the discharge chute in the transport position, less shoveling.

[Brucer]

To make a straight cut, a bandsaw blade is moving at roughly 100 km/hr, or 60 MPH.

I've never had a blade come out the side (yet) but ...
- I've had blades break into two pieces and the shorter piece try to come out the chute.
- The middle safety finger in my chute is bend 1/4" from blade impacts.

And when I ran another guy's mill ...
- One of the safety fingers was broken completely off.
- The heavy rubber chute had a hole punched right through it by a broken blade.

And before I worked for him, he didn't fasten one of the bandwheel covers tightly. A blade came off the bandwheel, hit the cover, and threw it down the entire length of the mill. There's a 2" long slot in the cover that the blade cut before it got rid of that pesky cover.

Bottom line -- it doesn't happen often but when it does it can be lethal. It's so easy to not expose yourself (or anyone else), why take chances.

[Peter Drouin]

Over the 24+ years of sawing I had one come out of the chute by 2 to 3 ", most times it stays in the log and now with the super the blade all ways stays in the log, and I cut out all the fingers in the chute, some times a peace of bark would get in there and stop the saw dust coming out , I don't like that :D :D ;D

[woodandtractors]

On my Baker mill the worst broken bands are sticking out the sawdust chute about 6" and folded. I think I am more likely to have a heart attack from the sound than anything else. The only way to stay 100% safe when milling is keep your hands in your pockets and don't start the engine-won't get much done,but won't have to sue the manufacturer. After over 30 years of working in a large circular sawmill operation with all its hazards,running the bandmill(to me at least)seems about 90% safer. I know each brand may have its own hazards,but stick to basic safety rules and talk to the more experienced sawyers on this forum for their advice.
Mike

[bandmiller2]

Over rated danger,just stay away from the discharge,more sawyers are barked up handling DanG bands than from when they brake.Wooden covers on the front of the band guard tend to catch the band and not damage the teeth if it just runs off.Real danger is heavy logs dropping on body parts. Frank C.

[Chuck White]

Last summer I was sawing White Ash and powered up just in front of the log and "BANG", the blade broke.

So, I returned the sawhead to the front of the mill and took the covers off to remove the broken blade and, no blade!

I looked over on the exit side and there was the blade laying out flat on the ground!

The blade exited through the sawdust chute with the 4" rubber hose, completely out, and the closest end of the blade was about 6 feet from the mill.  I never saw or heard the blade exit.

About 2 hours later, I had installed 2 bolts up through the sawdust exit to stop the next blade, haven't had a blade exit since!  ;)

[AdamT]

When I picked up my mill from Wood-Mizer, they told me not to cut out those fingers. He said some people do, and when we service a machine with the fingers removed, we have to reinstall them.

They're there for a reason so I'll keep em.

[Dave Shepard]

They do eject with some force. That's pretty heavy wall ducting and it went right through. I always warn people to stay away from that side of the mill, and shut down if anybody goes near the sawdust chute when it's running.

[dboyt]

I've broken a few blades on the Norwood MX34, always due to blade fatigue, and it happens fast.  I've never had one come out of the chute, but the plastic wouldn't slow it down, so the 50' precaution is a good idea.  Also, there is the distraction factor.  You can pay more attention to the job if you aren't worried about people standing in potentially dangerous places.  Teach the people working with you or watching you how to stay out of the way!  All my bruises, dislocations & lost fingernails have been from handling the logs.  Oh yes, when you replace the blade, someone will invariably step in to help.  Don't let them!

[Ianab]

As well as the basic speed the blade is travelling at, I'm also guessing it's possible it could get caught, bent into a tension situation, and then break into smaller (and faster) fragments from the tension it was momentarily put under? Means all sorts of weird pieces of shrapnel could start bouncing around.

There is a good reason to have those guards, and keep a safe distance. Not because it happens often, but the consequences of being hit are serious. 99% of the time the broken band is well behaved. 99% of the remaining time the guards will contain the shrapnel. But it's still more likely to happen than say winning the lottery. You improve your odds even further by not standing there...  :D

Ian

[trapper]

I make everyone stay to the front of the mill when I am sawing.  Once had to shut down the mill to get a maintainance mechanic from work who I was sawing for stay in a safe area.  With all the safety training we had he should have known better.

[GDinMaine]

The previous owner of my mill cautioned me about not letting anyone stand near the sawdust chute.  In about 20 years of sawing he had two broken, but complete blades come out the chute.  I take his word for it and keep people well away from there, while the blade is turning.

[muskoka guy]

Thanks for the input. Just makes sense to stay away from potential danger. Happy milling.

[schakey]

Spent 27 years in a machine shop,saw a lot of things happen that wasn't suppose to on both manual and cnc machines.
Don't be gun shy but always be alert and most of all be safe and have fun sawing.