Unless your grinding some of the exotic inserts and inhaling the dust, or machining beryllium, you are probably no worse off handling the more common alloy steels than you would be eating a Big Mac. Not that there's anything wrong with that... ;) Bob, what company did you work for? Guy Quoting Bob Grant <bobmgrant@hotmail.com>:
Joe-
Can you direct me to a source detailing more specific hazards of machining steel?
Yes, I do cut steel, and you probably have too, if you've ever used a hack saw. I'm certainly no expert on this topic, but by expressing my thoughts, maybe we can get input from others. My dad died from asbestos inhalation dating back to the aftermath of the Pearl Harbor attack, and in a sense became a victim of the attack (through corporate negligence of the known hazards) 50 years after the fact. I'd like to know of any hazards that I might be exposing myself to, so, y'all, please speak up. I think that steel is one of the more benign materials to work with. (Coolants and cutting fluids present their own hazards.) I have never heard of any dangers from the components of steel due to machining it, and I have just spent 9 years selling cutting tools to manufacturers and machine shops. I'd like to know more about what you are referring to. Some of the alloying elements in steel might be hazardous in the elemental states, but the worst of these (in commonly available steel) that I can think of off the top of my head are lead, sulfur and phosphorus. Sulfur, and I think lead, were considered safe enough to have come in my childhood chemistry set. These are locked in the crystalline matrix of the steel, probably aren't released in the machining process, and typically make up only .05 to .30 percent of the steel. Steels are dipped into nasty pickling stuff for either heat treating or metal plating operations. The plating plants that I have visited were noxious! Plating is usually done after a part is machined, so cutting plated steel is not very common in manufacturing. It is common for field operations or repair work, such as plumbers cutting threads in galvanized pipe. But at this point, only the metallic plating is present, and not the chemicals used to apply it. I know that welding plated steels can produce toxic gases. Galvanized steel is very common, and a steel that I know not to weld for safety reasons, but I have never heard that it is unsafe to machine. Outside of steel, I have heard that some more exotic bronzes are hazardous to machine, but I believe that this is due to an inhalation problem with the dust it produces. I see a lot more risk with dust producing materials like wood and fiberglass than I do with steel, which forms an elongated, continuous chip in most cases. Cast iron sometimes forms a dust-like chip when it is machined, as would steel on a grinder or sander, so these are cases where breathing protection may be warranted. However, these heavier materials drop out of the air faster than something like wood or fiberglass. Magnesium and titanium can catch fire when being machined, and these fires are difficult to put out. I've heard that machining mag wheels can get exciting real fast, and I've talked to customers who have had titanium fires, but these are pretty rare. I machined my eyepieces from titanium without the least worry of conflagration. I've visited the MagCorp plant west of the Great Salt Lake several times. The chemicals present in their process are so hazardous (chlorine, I believe) that I got turned away at the gate on my first visit because I was wearing contact lenses. You have to keep a respirator on your body the whole time you are on site, but magnesium itself is as safe to touch as aluminum. The tungsten carbide cutting tools I sold came with a hazard label on the boxes, but this referred only to grinding the tungsten carbide, where dust could be a problem. No mention was made of any hazard when using these products for metal-cutting, for which they were intended.
Bob Grant
----- Original Message ----- From: "Joe Bauman" <bau@desnews.com> To: "Utah Astronomy" <utah-astronomy@mailman.xmission.com> Sent: Sunday, October 31, 2004 5:30 PM Subject: Re: [Utah-astronomy] Surveyor Tripod Adapter
Bob, I'm wondering, do you ever cut steel? I know that is a dangerous proposition because steel has some nasty pickling stuff in it. But what's your take on that? Thanks, Joe
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