Angle grinders...

[NP99]

I have a 4,5 and 9 in angle grinders and recently had trouble using the 4in doing some cutting jobs. The discs shattered and broke pretty easy. The job was just cutting some aluminium posts.

After researching the web and reading about some of my bad habits which I wasn't aware of, I thought this the place to ask of those in the trade.

What disc for what job and how to apply disc size and wattage of the grinder to a particular job.

Also read that the 9in grinders have been banned on worksites!

[megatexture]

I use my 9" heaps and demo saw a fair bit and never heard anything like that yet ?

[TPC]

All building and mine sites in SA have banned 9 inch grinders.

[megatexture]

Next they will try and make you keep guards on them!

[NP99]

The 9inch is a monster of a tool. I can see why they have been banned.

[Clunk]

From my understanding and from what I've been told, when ally is cut and heats up it can clog the normal cutting discs (mild steel) which can cause them the catch on what your cutting and then shatter. I've been told if you rub plenty of surfboard wax on the discs it will help prevent clogging but you have to keep the disc waxed up. I've been told cutting discs for Ally are not for the faint hearted either and it's probably best to use a saw............

Not my opinion but just passing on what I've been told by someone in the know.

[jack]

Aluminium is fairly difficult to cut with an angle grinder.
I recently purchased some checker plate and had it cut close to size with a guillotine but knew it needed some more minor cutting when I got home. I discussed this with the fabricators and they told me to use the thinnest blade possible and to lubricate the blade to keep it cool. They used pig fat on thier angle grinder. Because Aluminium is such a soft metal it melts into the blade, try using a bench grinder and see how quickly it blocks the stone wheel.

Also 9" grinders are banned at all BHP sites and I think all WA mining sites as well.

Edit: just saw Clunks post

[TPC]

I was told when I did my apprenticeship a few decades ago that aluminium does not go near grinders or linishers, the guys in the metal shop would string you up if you tried.

[NP99]

After doing it........can't agree more!

[Ben-e-boy]

1mm turbo wheels, a grinders best friend.

Most sites I have been on ban 9in grinders BUT.... You can use a 7in grinder which has the same size motor but smaller disk.