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View Full Version : Grinding wheel Regs. (One for the Trainers!)







Grizzly
21-05-2013, 08:45 PM
Having done the above Several times during my career.
I am confused with the regard to slitting disks.

I was always taught you did not grind or cut (with disc's) non ferrous materials.
As these materials have a tendency to clog the pores of the disc or wheel.

Which, when heated by the friction generated in their use.
Would cause the clogged particles to expand and shatter the disk or wheel.

Nowadays with these much thinner and denser cutting disc's, is it acceptable to use these on say!
Copper pipe?
Thanks.
Grizzly

install monkey
21-05-2013, 08:51 PM
i use 4 1/2 inch grinder all the time- usually inox discs- 1mm thick, cut steel,copper,even cut floor tiles with em- as long as you only cut theres no issues, any use of the side wall of the disc can cause it to shatter, also discs have a shelf life again that can create failure- even cutting slotted channel, if the material twists and grips the disc its gonna result in consequences

Grizzly
21-05-2013, 09:14 PM
Thanks IM.
I knew about feeding them correctly and all that.
It's just I was nervous about copying the younger guys that did not have the same reservations, when it comes to slitting Disc's on non ferrous.
I myself use them all the time when slitting Ferrous and stainless steel.
Grizzly

Andy AC
21-05-2013, 10:02 PM
I've got a 125mm cordless grinder and I use those discs for just about anything- unistrut, stud bar, plastic trunking, cutting out old copper pipe etc. Even with a chunk missing out of it, they just keep going. If I was using them on a mains powered grinder I would be a bit more careful because of the higher speeds.cutting copper pipe eats the discs very quick, but much quicker than a junior hacksaw.

andy32
01-06-2013, 12:05 AM
will they work on wheel clamps

Rob White
01-06-2013, 01:15 AM
Having done the above Several times during my career.
I am confused with the regard to slitting disks.

I was always taught you did not grind or cut (with disc's) non ferrous materials.
As these materials have a tendency to clog the pores of the disc or wheel.

Which, when heated by the friction generated in their use.
Would cause the clogged particles to expand and shatter the disk or wheel.

Nowadays with these much thinner and denser cutting disc's, is it acceptable to use these on say!
Copper pipe?
Thanks.
Grizzly


Hi Grizz.

I don't think it is such an issue nowadays because
of the way they are made, I use sliting discs to cut copper
and I have never been told not to.

I do know someone who teaches the abrasive wheel course
though and I'll ask him next week.

Regards

Rob

.

Rob White
01-06-2013, 01:16 AM
will they work on wheel clamps

Yes............... :D

Rob

.

Grizzly
01-06-2013, 10:28 AM
An update would be good Rob!
I have been using the ultra thin ones that are used on stainless steel.
To cut 3 1/8" this last week. Very impressive!

Grizzly

glenn1340
03-06-2013, 08:01 PM
Abrasive wheels course? I did mine in 1970 from what I remember you shouldn`t use non ferrous material on a grinding wheel as it can load the voids between the grits and you`ll end up with a smooth surface that`ll need re-dressing which makes the diameter smaller every time that`s done. A loaded disc an angle grinder is not a problem as the wheels are inexpensive but on a fixed grinder they can be pricey and you can`t nip into Screwfix to get one.

Rob White
07-06-2013, 09:29 AM
.

I've had a word with a colleague who teaches abrasive wheels
and believe it or not there is no national standard for this qualification.
Basically anyone can deliver the training and issue a certificate,
the training is classed as "in house training".

So when it comes down to what you can and can't cut with cutting
discs it is always put back onto the manufacturer's instructions.

If the manufacturer says don't cut non-ferrous metals, then don't and
if they say it will cut anything then use them for anything.

Where there is an issue or an accident, if you where using
the blade to cut copper and the instructions stated not to be used with
non-ferrous then there might be issues if you are trying to claim on insurance.

Basically the training is for guidance and manufacturers instructions should be
followed at all times.

He then went on to say that most good quality cutting discs now will deal with
copper swarf because they are so dense the swarf can't get into the disc.

Rob

Ps Found on tinter web

Summary of Tips for successful cutting

In general ferrous materials are cut with a bonded aluminium oxide
cutting blade whereas bonded silicon carbide cutting blades are used
for non ferrous materials

.

Grizzly
07-06-2013, 04:59 PM
Thanks for the input Rob.
You are right about the training.
When i did it originally in 1974 (When the regs first came out).
The emphasis was on Machine shop / tool rooms.
Which was 6 1/2 day courses at the local Poly!
But they where very specific about grinding Non ferrous.

The one I did a couple of years ago was the same day and I don't think it was a long one at that!

I have yet to find a disk that is marked up as suitable for non ferrous.
But to be fair the very hard and thin ones that cut Stainless seem impervious.

That said.
The official answer is no then?

Grizzly

Rob White
07-06-2013, 08:17 PM
Thanks for the input Rob.
You are right about the training.
When i did it originally in 1974 (When the regs first came out).
The emphasis was on Machine shop / tool rooms.
Which was 6 1/2 day courses at the local Poly!
But they where very specific about grinding Non ferrous.

The one I did a couple of years ago was the same day and I don't think it was a long one at that!

I have yet to find a disk that is marked up as suitable for non ferrous.
But to be fair the very hard and thin ones that cut Stainless seem impervious.

That said.
The official answer is no then?

Grizzly


It always seems to be no when health and safety guys are around :D

Rob

.

Grizzly
07-06-2013, 08:59 PM
It always seems to be no when health and safety guys are around :D

Rob

.

No disrespect to others.
But you are too grounded to be a trainer Rob.

I feel Health and Safety was hijacked somewhere along the way, together with HR.
Which was always about a mutually benificial compromise or resolution.
But is now about limitting Liability!

Grizzly

andy32
16-06-2013, 10:24 PM
only if you dont get caught