Hello All, I got a rather gruesome reminder of an accident that I had about 12 years ago. Flexovit left a CD rom for my partner and I to look at and use to try to press home some of the things that can occur when using grinding wheels, cut-off wheels, thin blades, and many of the other types of friction cutting or grinding items. In my case, I was building some light duty frames from angle iron. I cut a bunch of parts on the friction saw and needed to deburr the ends, I also had a bunch of copes that needed to be cleaned up. That internal light bulb came on(THIS WAS ONE OF THE BIGGEST MISTAKES OF MY CAREER) that told me that using an air sander would be really quick and would be really light weight so that it wouldn't be hard to maneuver and manipulate. In the back of my mind I knew that the rpm. rating on the grinding wheel that I mounted on the sander wasn't rated for the speed of the sander, but I figured that I could throttle the trigger back and not have to worry about it. The larger the grinding wheel the lower the rpm. rating that it has, in my case, the air sander was capable of turning around 23,000 rpms., the wheel that I mounted on it was good for about 15,500. To make the long story short, I was in the process of taking a burr off of an end of a piece and all of the sudden WHAM...BOOM! Felt like someone sucker punched me. I did have safety glasses on and a face shield, but the shield went flying and so did the safety glasses. Reached up to rub my cheek and as I withdrew my hand I noticed quite a bit of blood. One of the other fellas in the shop came running over to see what had happened and by the look on his face I knew that there was something seriously wrong. I made my way over to the first aid shack with the help of my co-worker and the jobsite first responder met me there. Got the bleeding stopped and sent me on the way to the emergency room. The wheel exploded because of over-speeding on the air sander, as the wheel disintegrated one of the pieces hit me in the side of my face like a bullet, it almost went through to the inside of my mouth, left a gaping gash that was about 4" long and opened up like a split melon. Started about 1" to the side of my nose and went down around the corner of my mouth and towards my throat. Had x-rays to check for broken bones and teeth and spent 4 hours in surgery cleaning everything up and putting everything back into place and getting it all stitched up. I got lucky, my facial nerve was laying inside of the gaping crevice, but was untouched, similarly my salivary duct was also untouched, but definitely exposed. I could have ended up with a bunch of permanent damage to nerves and other things, as it is, I have a scar to remind me all the time of my stupidity. When my wife first saw me all she said was nice face Frankenstein, I had expected a bit of sympathy, but instead I got what I deserved from her. I tell my students this story all the time to try to impress upon them how important safety can be. I know first hand. The main point to this post is to try to put across how safety cannot be stressed enough with power tools. Any time you have a rotating mass that is capable of cutting, grinding, or gouging something, it won't think twice about having any consideration for your body or associated parts. The CD rom that Flexovit provided to us has actual photos of injuries that have been sustained by individuals who were using grinders, and other abrasive cutting tools. If you want to impress the importance of using guards, proper technique, and other safety issues for power tools, this is one compilation of photographs that will open your eyes and that of others. It is gruesome, but if that's what it takes to save someone from the heartbreak and pain of an injury I say show it to them. I will try to get the information for a contact to get copies of their package, as soon as I do I will try to attach it to this post.
good story, i should let my coworkers read this, just today i had to argue with someone about the exact same thing, using a 9 inch wheel on an air grinder that is made for 7 inch wheels, after showing him the ratings on wheels and grinders he agreed but hesitated to change it, after my rufusal to work next to him he finally changed it!
I've seen this with the disks that we use for underwater grinding, the water will slow the stone enough that you can use the air grinder with that wheel. But when you test it on the surface before sending it in the water you need to put a lot of pressure on the disk so that it doesn't grenade. I've always preached learn from others mistakes so that you can avoid injuries to yourself and others. Thanks for the reminder.
Charles Welch
DANG Allan.....good post and a helluva hard won lesson. You make me feel like a luky individual with a story like that.
Warned a fellow about his untucked shirt once...shop full of unguarded wildcats with 10 inch wheels...later that day he had his shirt wrapped up in that wildcat up to his neck....he was lucky. I was using the same thing an unguarded wildcat under a 1 ton truck I was doing a long frame extension on.....caught an edge just right and bounced it into my left thigh....still got a 6 inch scar/depression on top of that muscle that makes people stare at the beach. Check cutoff wheels on chopsaws or anything else before you use them ....it does not take much pressure to crack one...(tubing bounced off the blade during rough handling...next guy was lucky he was standing to the side when he started it). I make a habit these days of testing new wheels by running whatever the tool is full rpm with my body out of its plane of rotation...I have had fresh brand new wheels let go right off the bat....I suppose because they had a crack or other defect I did not notice. And since we are on the subject...I caught a mechanic just the other day using a bench grinder (stone wheel) to grind a piece of aluminum....ummm wrong answer dude. It was the same grinder I use for tungsten and I am glad I seen him do it so I could dispose of the wheel. I asked for some placards to be put up for safety's sake. Allan I got a good story for you similar to yours involving a fork truck and a young weld shop supervisor in a hurry to finish up for a hot date....If I can ever catch you on msn or something I will tell it.
Best regards
Tommy
Hard lesson learned. Hopefully your experience will save another accident from happening to one of your students.
I would really appreciate info on how to obtain that cd-Rom. Would make for an interesting safety topic at our next meeting.
Hello new tito, I did find out that this was a safety presentation that came from flexovit and that it had been emailed to my partner at our school here. If you would like to email me I will forward a file of this presentation to you. That same offer goes to anyone else who would like a copy of this safety presentation. It is too large to attach here. Send me an email to: aevald@lcc.ctc.edu and title your email "safety presentation", I will try to forward this to anyone who is interested. Best regards, Allan
great presentation Allen, thanks i have already made a cd for our safety dept. and they plan on using it and posting some pics on our safety wall.
Hello ctacker, you're welcome. I do believe after seeing this a great many folks might reconsider putting themselves in the "Bite" so to speak. Best regards, Allan
i know i did, i have worked steel 30 years, and besides the occasional dust that settles in my eye,(i have always slept it out) i have never been to the doctor for an eye injury. never, not even for that little dust.
and i have always kinda rebelled against the face shield. but for the last 2 days, i have not picked up a grinder without one. it has had a great effect in our shop. again thanks!
It is amazing how long it takes for a grinder wound to mend!
We've all been there and dun that. It's a rite of passage.
"You can always tell a welder, but you can't tell him much."
My father always told me that pain was the best teacher. His only remark after the first and only warning went unheeded was, "Betcha don't do that again!"
Put the fork into the electric outlet, "Betcha don't do that again!" That got my attention!
Change a switch without pulling the fuse first, "Betcha don't do that again!" Saw black dots for the rest of the day!
Use a match to light an acetylene torch, "Betcha don't do that again!" No eyebrows for a month.
Put the five gallon gasoline can on the cab of the truck and suck on the siphon hose, "Betcha don't do that again!" Left gasoline rings in the toilet for a week after that one! Talk about smelly burps!
It's a wonder we live as long as we do!
Yes, the examples can go on for pages!
Best regards - Al
Hello people. I think the most problems are when you let your gaurd down, I mean not reminding yourself of the damage the gringers or cutters can do. I was cutting off a brace with a 0.45 cut off wheel on a 4 1/2" grinder with the sparks going away from me, and just when I thought how stupid it was it spun around in my hand, cut between the vains going parrell to my arm on my wrist. Got real lucky. The key is to stay alert, that's what I teach new people???
We use to take a chop saw blade and build a stand off of a Milwaukee hog grinder and 5/8" all thread rod bushed to blade for demo cutting many years ago, I was just a cub and my journeymen showed me. We got lucky nothing bad happend and yes it worked. I would never do it again! and reading this thread that was the first mental picture I had was that hog grinder with a 14" (l.o.l) blade spinning, with the centrigal force you could almost go airborn with this rig. Never again and I won't show my cubs that crazy trick (l.o.l)
yea crazy things happen, and when people who dont know what they are doing, trying to show others how to do it is really dangerous. they need to swallow there pride and ask for help. see it all the time.
Good one Allan, must have been your lucky. I have a similar incedent that occoured for different reason to buddy because agrinder was set on the ground with the disc in the dirt, it had been stepped on and cracked and buddy did not notice it so when he picked it up and put it to steel the disc exploded he came close to loosing an eye. So for that reason a pet peeve of mine is all grinders are layed down with the disc faceing up.
My story is kinda pale compared to some but I am a farmer not a welder so I'm allowed to lag behind, maybe. I was using a plain little 4" B&D like we all have, paused to check my progress, and instead of setting it on the ground, grabbed it between my knees. Heard the switch click and quickly, instinctively dropped it without damage to anything. But, when I think what coulda got ground........ The point is to never lose focus when working with ANY KIND of power tool.
Amen ,that could've been bad
Lucky.
I've had wheels jam up, and that can easily throw a grinder at you, even a 4" one.
That's one thing I really like about my Metabo grinder. The safety clutch.
It just slips if a cutoff wheel grabs in the work.
The slow spool up of a Metabo is also a really nice safety feature. This weekend a co-worker was cutting straps out of an inconel on carbon tube test coupon. When he started it up he had one hand on the trigger and was moving his left hand onto the body of the grinder(6" Dewalt w/ a cutoff wheel). The torque immediately spun the wheel into the skin between thumb and forefinger, cutting an artery and requiring 4 staples. He was wearing leather gloves, ear plugs and a faceshield, he had used this exact grinder in similar situations many times before. The company had a safety stand down and complacency and job sitution comfort were found to be the root cause factors. 7/12's doesn't help matters either. Our work will always be as dangerous as we allow it to be.
Ouch! I simply cannot read that without cringing.
I'm just a hobbyist, so with a budget of $0 its real easy to be tempted in by HF tools and prices, but I've been careful to stick to the good stuff that comes with the safety features. Added longevity, smoother running, and more power than the chinese tools, is just icing on the cake for me. Dewalt makes great stuff, but with welding as bad/ugly as mine, I had to get the best grinder available. :)
Of course, cool safety features are never a substitute for proper safety procedures. That's something I wish I had more formal training in.
My grandfather got his first set of dentures from an exploding bench stone(pre vitrified bond).
Power tools- they are stronger than you and faster than you.
My Opinion" those 4 1/2 inch wire wheels made for a side grinder are one of the most dangerous tools on the planet. Guard in place or not. I had on all prescribed safety gear and that little devil bound up in a channel iron, jumped out of my hands and went right across my wrist. Luckily, I only got a road rash, but it could just as easily have taken out all those suicide arteries. And even if all goes well, those little wires can and do imbed in your body and you may not even notice it.
As an added bonus, I had it on a dewalt with the lock on switch and was using my welding hood as a shield so I could not tell which way it went after it chewed on me and it was still running. Last time for that!
Hello mooseye, you won't hear me say that I disagree with you. Unless there is some really good reason for me to use one I avoid them like the plague. Just like you, I have had them come after me and get a hold of me on an occasion or two. Have seen the little black spot that looked and felt like an ingrown hair only to find a length of wire brush embedded in the old body. Much rather use a sanding disc, flap wheel, needle scaler, sandblaster or some other less intrusive method. And yes you really have to look out for those trigger locks on any sort of grinder. Although the wire wheels do have their place in our working world and one only hopes that the folks who end up using them will take extra care not to feel their bite. Best regards, Allan
what I do with those stupid trigger locks is (on my makitas, that's all I own): take your grinder handle apart to get to the trigger assembly, take a pair of side cutters and cut off the lock-on pin, usually the remainder of the pin falls out the bottom side, re-assemble and whalla. Now you got a grinder that's a little safer. And if you re-assemble and the grinder won't turn on when the switch is pulled then there's still a little piece of the trigger lock pin left in the trigger assembly, In my opinion doing this in no way compromises any sort of operator safety because even if it don't succesfully remove all of the pin your grinder just won't start, there's no way those pieces can keep the grinder running at all.
About doing the above (trigger lock mod): i assume you'd have to keep the switch pulled the whole time you're grinding, right?.. or would the switch just stay there?
i'm tired of my dewalts, i guess they don't last very long. heard bad reviews about their grinders. so, i did some research and just got a set of makita's. it was either makita or metabo, and nothing else.
Wich DeWalt models were You having problems with?
Not sure what model my Dewalt is but is a small 5 amp grinder. Switch started acting up the first week I used it. Got to hold it all the time.I still have my first grinder that I bought 25 years ago,and it still works fine,use it all the time out in the oil patch. It`s a Metabo.
It is hard to beat those older Metabos. I have quite a few of the Black & Decker/Dewalt 4 1/2" grinders with the metal gear case and the paddle switch, most of them are the older 6 amp model, the newer ones are 7.5 amp. These are good ones, not made in China. I think they are presently made in Mexico. Some of Mine were sold by Sears or True Value and have a handle like a big grinder, but the motor & gear case is the same. The Black & Decker/Dewalt "Wildcat" 7"-9" grinders with the aluminum motor housing are good ones if You come across any, I got Mine used from pawn shops & flea markets.
I have to say Dave I have dropped wildcats off 18ft dia tanks to concrete with no ill effect. Wildcats are serious heavy grinders...I am not a huge fan of B&D but I have had 'certain"drills and definitely any wildcat hold up under the WORST of conditions. Reconditioning service on the wildcats is good to...they rebuild them right. Actually I do not think there is a better Heavy 10" grinder out there....sorry I have just seen them take WAY to much abuse...stuff that would bring any milwakee (made after 70) and any dewalt to the junk pile. Matter of fact my last one was stolen so if one of you want to dump yours PM me...I might buy it.
Tommy,
We have a shop full of those grinders, approx. 50 in the 9" variety and one that is 4.5". They do take some abuse, many of our guys have put saddles on them and rode them...LOL. We keep tons of parts in stock to completely rebuild them. They get dropped on the concrete all the time, usually hard enough to bend the adapter that holds the grinding disc, or even break the cast housing, but they bring em into the maintenance shop and rebuild the entire grinder in just a few minutes, whether the motor is burnt up, gears stripped out of the nose, housing busted, or what have you, they can get it fixed back up and put back in service. Rarely do they ever throw away a grinder and replace with a new one.
I like and have had good service from the "Professional" and "Industry and Construction" lines from Black & Decker. The home owner stuff they made is junk, built to a low price & quality level for people who don't know any better. Those 10 amp 1/2" & 3/4" drills are monsters. One of My 14" portable chopsaws has the same motor as a Wildcat grinder, but a different gear drive. For a while the "Craftsman Commercial" line was the heavy duty B&D products, but often the older model, and with a cheaper cord. Sears had to do something to screw it up. Some of the heavy duty B&D tools came in yellow with the DeWalt label, I don't know which if any of those are still avalable new.
If the sticker shock won't cause the nerve from your hand to your wallet to spasm then the Hilti grinders are worth the toll. Years ago in Los Angeles I worked alongside a group of guys called "sackers." These are the guys who repair the casting defects in conreete tilt up panels to make them look so pretty! They grind concrete all day every day and their equipment takes a beating as a result. Picture if you can, grinding concrete with the dust from the operation being constantly cycled throught the body of the grinder by the cooling fan within. Quite a sight for sure. Anyway they all use Hilti Grinders cause they hold up to this torture. None of these guys had a back up grinder on the jobsite either. I used one of their well used grinders one day and liked the ergonomics so I bought one. Now ten years later with the same 4.5" grinder and only a new power cord as repair I can say they are well worth the money. Only problem is fact that others like them too and I have had to "retrieve" my wayward grinder from another mans possession more than once.
2 of the B&D "Wildcat" grinders and 1 of the 4 1/2" B&Ds that I have were used by granite or terazzo guys, that does fill them with grit. These came from pawn shops. I did see a lot of Wildcats that had been used on stone or cement, the silicon carbide cup wheel would be a giveaway even if they cleaned the crud off. I have seen Hilti grinders in pawn shops, but not often.
My old boss told me about wire wheels. He was using one to clean a vertical joint, and it bound up into his flannel shirt and his gloves. He was unhurt, but his hands were locked up in his shirt, and just about the time he was thinking about how to get his hands free, he noticed that the trigger was still on, and the motor started smoking. Fortunately he was able to yell to a buddy and get the extension cord unplugged. I always think about that when I am at my shop working alone.
I was on a pipeline job on the Western slope of Colorado and witnessed a helper take a brand new 7" wheel and smack it repeatedly against a scrap piece of metal, putting small grooves in the edge of the disk. I immediatly stopped him and informed him of the dangers of a fractured wheel. He told me he was taught to do this in order to make the wheel grind more effectivly. I will never condone this practice but was just wondering if there are any pipeliners(is say pipeliners due to the fact this was the only time I had witnessed it) out there that could elaborate on this practice?
Sounds like a quick way to end up in the ER....
Yeah, he stated that his granpa showed his daddy and his daddy showed him and his best pal "DeeWaayne" said for him to do it as well. Scary to think that people that care about someone would give them such bad advise.
thats a bunch of bs i mean come on common sense
michealb I found out a while back that common sense ain't very common.
Common sense is only common to those who have it.
Yikes, thats scary.
I've used grinding wheel dressers to remove the glazed surface you sometimes get on wheels. It definitely speeds the grinding up, but I've only done this on 4.5" wheels.
Hello guys,
Another one that is all too common and pretty damn scary is with the "drop" saw or cut off saw. Not sure if that is the name you use in the US.
Forever see people cutting bolts or round / square bar in them and then using the side of the cut off blade to clean of the burrs/sharp edges etc. Hold it on for long enough and it creates a groove in the blade.
Then someone else comes along to cut something, puts a bit of weight on the blade and it explodes.
Not a pretty sight !!!!
Regards,
Shane
I have seen this happen as well. It truly is scary to see. I honestly beleive that practices like this should be thoroughly covered in oreintation and listed as a terminatable offense for the first offense. When a chopsaw blade or large grinding wheel explodes, it does not discriminate about who it will injur. It can take out the person operating the grinder/saw as well as bystanders who have no control over the situation.
John
Hot day. Unbuttoned shirt. Old Sioux grinder (lots of power) with wire cup buffing wheel. I was young. Had my shirt wrapped up in the wheel in about 1/10th of a second with the cup right under my chin. I, too, had difficulty letting go of the trigger, but just enough strength to fight the wheel off. No injuries (lucky). When I was a leadman, I ALWAYS had guards on my 7" grinders. One of my guys transferred to another crew for a day. He forgot that that leadman didn't insist on guarded grinders and let the still spinning wheel rest against his "privates" for just a second. Cut through his pants and made his wife unhappy for a week or two. Also very lucky. (He said the worst part was having the nurse scrub the wound)!
Dan
OUCH! It only takes, as you have stated about 1/10th of a second to gain a very high level of respect for a grinder, especially large ones. I have had a few close calls that thankfully did not result in anything but very minor injurys and a very high pulse rate for a few minutes. But I have been witness to some nasty injurys resulting from careless use of grinders, and believe you me, when I say this, I took those experiances TO THE BANK!
jrw
A 4 1/2" grinder with a new wheel going at 10,000 RPM, if you could set this on the ground it would go around 160 MPH. You need some pretty quick reflexes to beat the grinder speed.
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