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View Full Version : Should I wear a dust mask while cutting steel with an angle-grinder?



Rocker
7th February 2007, 04:46 PM
I was using an angle-grinder today to cut up some rebar which had been used to make cages around trees on my block. I noticed that the abrasive disk is reinforced by threads of what looks suspiciously like asbestos cord. Is it advisable to wear a dust mask while using an angle-grinder to cut steel?

Rocker

SPIRIT
7th February 2007, 05:02 PM
never seen or been told to and l worked in a full on worksafe site
so l say no :no:
could be wrong :? see what andy will have to say

martrix
7th February 2007, 05:27 PM
don't recall any warnings to use dust mask when angle grinding but I might in the future.

Have been doing a fair bit of metalwork lately and notice that I do get blackish snotty crud in the nose.:(

Its probably a good idea to go by the rule that any thing other than oxygen inhaled will have long term effects over a long period of time.
I also try not to breathe when I clean up the white wheel on my grinder with a diamond dresser and the big puff of white dust is released, isn't that silica?

Wallace
7th February 2007, 05:27 PM
Rocker/Spirit
The composition of the cutting disc is not the problem - but I ain't a great fan of inhaling rust dust and other shrapnel if I can help it - I try to slap on a mask at any opportunity - but in the tropics they get hot wet and sloppy fairly fast - and then hard to breath through - TAKE YER CHOICE KEEL OVER FROM LACK OF AIR OR PULL IT OFF.:doh:


HAPPY GRINDING GUYS

WALLACE:)

martrix
7th February 2007, 05:38 PM
I noticed that the abrasive disk is reinforced by threads of what looks suspiciously like asbestos cord.

Rocker

Could those threads be Fibreglass or Kevlar?:shrug:

Wood Butcher
7th February 2007, 05:50 PM
Rocker, it certainly wouldn't hurt to wear a mask. As Wallace said there is fine metal particles that float around in the air, mainly from the ceramics that form the disc.

Mirboo
7th February 2007, 06:36 PM
I reckon you should wear a dust mask.

On page 58 of the current Lee Valley Woodworking Tools catalogue, in the power sharpening section, the following information is given.

"You should protect yourself from the dust of dry grinding. In the mid-1800's in Sheffield, the life expectancy of an apprentice tool grinder was less than 20 years. This varied from 16 years for a fork grinder to 25 years for a knife grinder. They inhaled grinding dust for 60 hours per week. It is easy enough to rig an old vacuum cleaner, central vac or dust collector to control the dust. It is a favour you should do yourself, if not your heirs."

Rocker
7th February 2007, 06:37 PM
Could those threads be Fibreglass or Kevlar?:shrug:

You are probably right; but if they are fibreglass, it would probably pay to wear a mask. I suspect that the scarring that x-rays of my lungs reveal is probably due to inhaling glass fibres when installing glass fibre insulation batts in my house when I lived in the Old Dart.

Rocker

ozwinner
7th February 2007, 08:48 PM
I think fibreglass will be the new asbestos of the future .

Al :(

BobL
7th February 2007, 10:56 PM
Unless you have a really old or exotic disc the reinforcement will be fibreglass. During the grinding process the disc does not generate particles entirely back to its constituent parts (abrasive; eg Al203, reinforcement; eg glass fibre, and binder; eg epoxy) but dusts containing all 3 components, plus metal fragments. A fragment of Al203/binder/glass is not as dangerous as straight glass fibres. Despite this there will still be some straight glass fibres hence wearing a mask is still a good idea.

A more significant problem at times is not the discs but what is being cut or ground. If a piece of angle iron or tube has been attached to fibreglass or asbestos, or a bolt is poking through a piece of asbestos. then grinding these will certainly spray the stuff around

Skew ChiDAMN!!
8th February 2007, 01:07 AM
The answer is easy: if you aren't sure, then YES!

Always better to be safe than sorry. :rolleyes:

Wild Dingo
8th February 2007, 02:26 AM
Too bloody right!!

I mean have you ever coped a bunch of them red hot bits of metal up the snotter? BLOODY HURTS like buggary!! mind you a couple in the eyesockets aint to flash neither... wear the mask AND the glasses/shield

And for gawds sake stand UPwind of the bloody thing :doh:

Rocker
8th February 2007, 03:34 AM
Well thanks for the info. Actually I rarely use the angle-grinder for cutting metal; I usually use it for sanding wood with a sanding disk. But then I wear a dust helmet. In view of what you all have said, I will wear the dust helmet whenever I use it.

Rocker

martrix
9th February 2007, 11:21 AM
I have another question regarding an inhalant and working with steel.

When drilling steel in the drill press and using a cutting fluid there is a generous amount of smoke produced for a few seconds when the bit is fully cutting which comes from the cutting fluid.

I am using "Rapid Tap" and it says it is made from Paraffin, Chlorinated? It also says it does not contain 1,1,1-Trichloroethane and No Californian Prop.65 material.

What chemicals would be in the smoke?
As a caution on the tin, it says "inhalation-mild lung irritation"

Probably not as bad a cigarette though:rolleyes: :- .

BobL
10th February 2007, 01:56 AM
I have another question regarding an inhalant and working with steel.

When drilling steel in the drill press and using a cutting fluid there is a generous amount of smoke produced for a few seconds when the bit is fully cutting which comes from the cutting fluid.

I am using "Rapid Tap" and it says it is made from Paraffin, Chlorinated? It also says it does not contain 1,1,1-Trichloroethane and No Californian Prop.65 material.

What chemicals would be in the smoke?
As a caution on the tin, it says "inhalation-mild lung irritation"

Probably not as bad a cigarette though:rolleyes: :- .


An MSDS sheet is available for Rapid Tap from, http://www.barrettdiamond.com/carbide/pdf/nrtmsds.pdf
The general Health Saftey rating is low so it should be relatively safe to have around the shed.

However, as far as when it burns, the MSDS says. Combustion can produce acid gases (hydrogen chloride, hydrogen sulfide) and these are what would give you any irritation.

If you do this very often I would use a gas mask, for moderate - occasional use a fan to blow the smoke away from you for those few seconds when the smoke is generated would be sufficient to dilute the acid vapour. Since my DC vents outside my shed, I have a couple of ends of ducts that end in flexible hose so I hook the the end of one of these hoses to my DP table and it seems to catch most of this sort of thing.

Cheers
BobL

Gil Jones
11th February 2007, 05:07 PM
The only time you need the mask around dust is if you are breathing.
If you are not breathing you probably needed the mask, but it is already too late. I wear mine (with the proper filter cartridges) whenever I am breathing air with something in it besides air. Lungs are hard to replace :) .