Graphite

[TimTaylor]

Personally I wouldn't be overly concerned about breathing a bit of graphite dust. Of course you don't want to be choking in the stuff, but a little floating around in the air isn't likely to do much to you. It's just carbon and the particulate size produced by machining would be far larger than those produced from a campfire or even a burning candle. To keep the mess down I mount the nozzle of a shop-vac close to the chuck and run it when I'm machining. It does a pretty good job of containing the mess.

https://www.tedpella.com/MSDS_html/Carbon and Graphite Products msds.pdf

 

[moerman]

I don't know if artists supplies graphite can be used. It can be found in 3/4 inch diameter and about 6 inch long and comes in various grades. The hard variaties look suitable for making pistons.

 

[Rolland]

Tim
Thanks for the info sheet, helps a lot since this is my first attempt to work with graphite

 

[Cogsy]

https://www.tedpella.com/MSDS_html/Carbon and Graphite Products msds.pdf

That document pretty well mirrors what I said - no known chronic effects, so breathing a small amount would be just fine. The list of possible effects (coughing, etc.) is talking about breathing clouds of the stuff (which I certainly wouldn't recommend) and would be almost identical on a MSDS for water. It is not a carcinogen or toxic, which is what we're really concerned about.

 

[TimTaylor]

That document pretty well mirrors what I said - no known chronic effects, so breathing a small amount would be just fine. The list of possible effects (coughing, etc.) is talking about breathing clouds of the stuff (which I certainly wouldn't recommend) and would be almost identical on a MSDS for water. It is not a carcinogen or toxic, which is what we're really concerned about.

I don't disagree in principle with intermittent light exposure, but significant exposure to any dust can cause pneumoconiosis, and some individuals are more susceptible than others. The good news is that unlike silica and asbestos (neither of which is toxic or carcinogenic by the way) graphite dust does not cause fibrosis. Eye irritation from the dust is probably the most likely problem anyone would encounter.

Another factor to consider is that while that may be true of pure graphite, many graphite compounds contain binders or fillers to improve mechanical characteristics or control porosity, and it may not be true of those.

The likelihood of a hobbyist suffering any adverse reactions from machining graphite are minimal - I'm more concerned with the mess it makes. Cleaning up graphite dust can be a real pain, so I prefer to minimize the need as much as possible.

But why take a chance? We all wear ANSI approved eye protection when machining and a dust mask when grinding, at least I hope we do. Wearing appropriate PPE and controlling the dust generated will reduce any risk to almost nil.