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  #11  
Old 05-13-2014, 07:52 AM
Phil Minton Phil Minton is offline
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"I never use a grinding or cutting disc without a guard, I can't believe anyone would." - David

I totally agree David, though I did know a work colleague who did ( believe it or not a firefighter) He removed the guard to fit a larger cutting disc. This broke up at high speed and a large chunk went through his chest, knocking him off his feet and putting a cut in his aorta.

In his words " I felt alright laying there on the garage floor until I heard my mate (another firefighter) calling for an ambulance in the house and screaming down the phone "Hurry up, he's ****ing dying out there!"

He's still here to tell the tale but - Stupid, Stupid, Stupid......
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  #12  
Old 05-13-2014, 08:55 AM
Bob Foster Bob Foster is offline
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The guy's tatoo says it all. Those cut-off wheels are unforgiving when they cut loose!
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  #13  
Old 05-13-2014, 10:52 AM
weldtoride weldtoride is offline
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So far in this thread I haven't seen mention of matching disc speeds to the tool, other than these two consequences of NOT matching:

Quote:
Originally Posted by David Gardiner View Post
... American Chopper where they use discs which are far too big for the grinder without any guard....

Quote:
Originally Posted by Phil Minton View Post
.......a work colleague who did ( believe it or not a firefighter) He removed the guard to fit a larger cutting disc. This broke up at high speed and a large chunk went through his chest, knocking him off his feet and putting a cut in his aorta. .....
Forgive me if the old shop teacher inside surfaces for a minute: Every grinder; bench, hand, whatever, has a max no load speed. Larger diameter grinders turn slower. I just glanced at Milwaukee's catalog right now, one of their 7-9" grinders runs 6000 rpm; their 5-6" runs 9000 rpm, and one of their 4 1/2" units runs 11000 rpm, almost twice that of the larger.

Every disc in turn has a maximum safe speed. Putting a disc, even a correct diameter one, on a faster turning arbor than its design limit is asking for trouble.

Putting a larger diameter disc on a smaller grinder than it is designed for is begging for trouble, as the maximum safe speed is likely to be far less on a larger diameter disc.

When I taught shop, I had to keep all the abrasive discs in my office, after I caught a student installing a hard grinding disc rated at 12k max safe rpm on an air sanding tool rated at 20k no load speed. It fit perfectly well, and it was the same diameter, so why not?....

I have mentioned this before, quality abrasives can save money through better wear characteristics. I might add now that they can also save on drama.
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Last edited by weldtoride; 05-15-2014 at 12:45 AM.
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  #14  
Old 05-13-2014, 11:10 PM
fred26t fred26t is offline
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Default No guards

My 40+ year old Milwaukee never had a guard and I have felt the wheel a time or two. Felt it the most with a shrinking disk. I could see my knee cap (without the skin.) Fred 26t
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  #15  
Old 05-14-2014, 09:12 AM
Lister1
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Sand disc.
Was not too big in diameter, but the disc is caught the edge of the sheet, rip off the grinder out of my hand and stopped on the leg.
It caught pants with such force that it stopped, but it was still plugged


44.jpg
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  #16  
Old 05-14-2014, 09:22 AM
David Gardiner David Gardiner is offline
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Lis imagine what would have happened if you had a cutting disc on it.

David
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  #17  
Old 05-14-2014, 12:21 PM
lots2learn lots2learn is offline
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I bought a metabo 5 inch grinder specifically for using with cutoff wheels. It has a guard that adjusts without tools and a built in clutch. Also use a standard welding helmet with flip up lens and leather gloves when cutting.

Am also surprised that more people have not cut off fingers or had discs impaled in their faces more often. I’m not a safety Nazi by any stretch as I do many unsafe things but these cutoff discs just seem so obvious.
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  #18  
Old 05-14-2014, 03:40 PM
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Marty Comstock Marty Comstock is offline
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Only problem with cut off discs are operator error. Been suing them many years and only Tim's I got hurt or had close calls is,when I was doing something I.shouldn't have.

They come with a handle for a reason. Use it.

Blow the sparks towards you, that way if it grabs, the tool goes away from you.

Brace yourself, and your arms. Use your hands or fingers as a kickstand to the panel for stability.

Always assume the grinder will catch, keep yourself out of the line of fire.

You can do some very fine and intricate work with a cut off or grinder, if you follow these tips. Too many people are not skilled enough at grinding. Like welding, it takes practice.
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  #19  
Old 05-14-2014, 04:25 PM
Lister1
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Quote:
Originally Posted by lots2learn View Post
It has a guard that adjusts without tools and a built in clutch.
I have not seen such a grinder in the stores near me. Can you put a picture or link me to a page where I could see the grinder.
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  #20  
Old 05-14-2014, 06:58 PM
lots2learn lots2learn is offline
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http://www.metabo.us/Product-catalog...856a1cd.0.html

In the states they are sold at welding supply or safety & industrial stores. Never seen them at big box stores, Home Depot etc. Too expensive to put next to the dewalt and makita grinders.
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