Projects Anybody plagued with cutting wheel explosions !!!

I have use cut-off wheels for many many years at work and home and could count the times the wheel
"flew-apart"/exploded on one hand. (Most of the time it was operator error...)
BUTT......here lately I have had two disintegrate within weeks of each other !!
As you guyz know.......that's a scary thing. Especially when there is no guard on the grinder.
Is it just me or......??!
I did learn years ago to not stand directly behind the grinder while using it but the shrapnel still flies al over the shop!.
Harbor Freight is NOT know for high quality stuff so I may have answered my own question.
Have y'all noticed more explostions ?!!
6sally6

 

Our tool room person purchased a different brand of wheel , not cheap but cheaper than our normal brand. We had two explode in one month. She no longer buys the cheaper brand.

 

No problem so far.

 

I've had good luck with the Harbor Freight 4 1/2" ones.

Gary

 

When I ran the school bus shop, I started using the 3m Green Corp cut off wheels. The difference is night and day between them and all the others. The shop I work for buys the cheap ones and they just don’t last. Cut off wheels are truly an item where you get what you pay for.

 

I had one on a 9 in Wildcat Grinder explode , a piece flew 20 feet hit my Buddy in his chest hard enough to knock him down , cut through his shirt . That left a mark !

 

3M green Corp all the way if you can get them there fazing them out for the crappie purple ones don't go cheap on these and put that guard back on you will thank me later.

 

I avoid any H.F.'s sandpaper and cutting wheels. They wear too quickly and are prone to failure.

 

used to do testing on all the stuff pratt whitney bought for production. nothing like drilling/tapping thousands of holes per day. cut-off wheels, grinding wheels, etc have rpm limits depending on material AND who made them. norton products were the best to buy. think norton got bought out too, beware. best is to read up the stuff. ask those in the metal trade what they use/buy.
we use to have a big cut off wheel machine. think the wheel was like 24''. we would cut everything in it. wood, plastic, whatever. think the wheels were $150 ea then. we blew them up all the time. lol

 

money is always a issue , but in this case cheap will will sent you to ER , been there !

 

25/30 years ago I was doing the purchasing for the maintenance department of a big fruit juice processing plant. We were using the "thin" cut off disks a lot and it was those that were shattering most of the time. We just quit buying those and just used the thicker ones and didn't seem to have the problems that we had with the thin ones.

I'm thinking that a lot of guys on here who may be having disks shatter too often are using thin blades on double layers of sheet metal to get a precise cut for a butt weld and have them bind up a bit.

Last but not least, check the disk over every time you pick up the grinder to cut something, I've had them get knocked over and damage a disk/blade and other crap happen to them that may have damaged them.

 

Show of hands, who knows that abrasives have a shelf life? Old stock thanks to the shutdowns are a plague for sure.

 

I use the Harbor Freight smaller ones on my die grinder, and never had a failure. I do not run it at full speed. I know the media they sell is cheap, so I think it's a bit safer going slower. I guess I have been lucky so far.

 

And for peats sake use a face shield over your safety glasses.

 

I buy USA only on Ebay. They seem to last a decent length of time if you run them a bit slower. When I explode one, it's usually my fault.

 

Price, age, and thickness all play a role in cut off wheels exploding.
I break more cut off wheels by having the tool roll off the bench then I've ever had while in use. I buy the thicker, more expensive cut off wheels, and I only buy a box of 50 at a time (lasts me a bit less then a year).

 

I have had a few blow up over the years but the moments before they did I always had a suspicion I was getting a little too western.

 

Age? Why shouldn't this surprise me... ;( .
So what it that ages out? Resin, moisture absorption? IDK, which is why I'm asking. & just how long can you keep the discs, since I don't remember ever seeing a "use-by" date, although I do have some old-age vision issues. TIA.
Marcus...

 

We have very specific rules at work about cutting discs. They are dated (3 years from manufacture max) and have to be stored in a certain way. They’re used outside and any that get wet are thrown away.

 

Gotta be a use by date issue, or just switch to a different brand.

For the love of god please keep the guard on, if you have to take it off you're using the wrong tool in my mind. Not worth the risk.

 

Yep, two within a weekend. I buy a pretty good brand (Flexovit), as never had an issue with them and two went in one weekend. I thought it may have been a batch issue so hit the last 6 with a hammer (cant be used) and threw them away. I went and bought a new packet and no issues. I am pretty relaxed with guards and things but I put it back on and wore safety glasses! Pretty scary when you think what can happen.

 

really, who does that ?
I never use a grinder without a guard.
And 30 plus years ago when a teenager I knew, lost an important part of his anatomy from a 9” grinding disc going awol, I learned to reposition whatever I was grinding on……..

always buy quality grinding discs………see above comment in this post for the reason……..

 

I was a Jet Mechanic in the Air Force eons ago. We were always aware of the engine's "Plane of Rotation". The fan disc has a red line painted adjacent to it painted on the plane that tells you if the thing grenades, this is where it's going, so we always avoided being in that area. Same applies here, don't position your body in such a way that shrapnel can get you.

 

I use only Walter brand “zip cut” wheels on my 4.5” grinder. They last better than any other brand I’ve tried over the years. Not cheap, but worth it in my opinion On my air cut off tool I use the smaller 3M green core when I can get them. As someone else said, I think they’re being phased out for the purple trizact type.

 

Also a point to make: statements of "Lasting well" or "Wearing too fast" can show a slight lack of understanding of how an abrasive wheel works. Its not a saw, as a rule, if its wearing its working.

Make sure you are using the right disc for the right job.

 

Their sawzall blades bite the dust almost instantly too. Ace has decent cutting stuff usually on a display behind the counter on the wall. Well worth the money.

 

No guard is asking for a Darwin Award. I didn't know about shelf life, though.

 

Many of my thin disks have never lasted very long
they usually get broken as said prior by rolling off the bench
or stepped on when left on the floor
never had one explode

 

I always use the guard on my angle grinders and other tools. To not use one is asking for it. I don't use the super thin cutting discs either, too much potential for failure. Also, I always wear a face shield when using the grinder or rotary cut-off tools of any sort. It only takes a second for an incident that could change your whole life.

 

A guy I have helped build a couple of cars with was telling me his father ( who does wood working ) would snag the cut off wheels we had thrown away due to chips and use them. Before we could have a long talk with him, this happened. After the piece went through his cheek, it went through his gums and removed several teeth. He does not snag those wheels anymore.