Lapidaryforum.net
Gadgets, Gizmos, and Dohickeys => Cutting, Grinding, Polishing => Topic started by: ToTheSummit on August 12, 2019, 03:58:56 PM
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So heres the situation. Due to some unavoidable life situations this summer has been slow in my shop. Ok, lets be honest, I've barely cut anything this summer. Just a handful of cabs. And the 18" saw hasn't even been opened since late April. This week I got the bug to cut some rough so I went over to the 18" slab saw and opened it up. I looked down and thought "Damn, that oil looks dark!". So I grabbed a flashlight and shined it into the saw only to find that my oil had turned an amazing green color.
I've cut many different kinds of rock, and with the exception of psilomelane (don't ever cut that damn stuff until you are ready to change your oil) I have never had anything so dramatically effect the color of my oil. Even when I cut messy things like some red jaspers that stain everything the oil will always settle to a nice clear color when left to sit. In fact, my memory of the last time I looked into the saw the oil had settled clear. The mud at the bottom is still the usual brown muck you see in any slab saw that cuts a variety of different stones.
So of course when I see a bold green color like this I immediately think "copper". Then I remember that one of the things I picked up at Quartzsite in January was a big chink of Kingston Copper Ore and I slabbed it up in this saw in February. That ore is absolutely full of raw, natural copper. It makes dramatic slabs and cabs. But I know the oil did not turn green right away. Like I said, when it was last in use in April it still looked normal.
So my thinking is that somehow over the last few months as my saw sat in the summer heat of my garage some chemical reaction has taken place that dissolved the copper into the oil creating some sort of solution composed of mineral oil and copper. I dipped out some of the oil into a clear container to take pictures of it for you to see also. The color looks about the same under sunlight or my shop lights, and the pictures are pretty true to what the naked eye sees.
Now my question. I do not worry about this affecting any other stones I cut in it since I doubt this will discolor any other stones (although I might try a test run on some things that seem more porous just to see), but my main concern is could there be a health risk involved here? And has anyone else ever had such a thing happen to their oil before? Any thoughts you guys have would be appreciated.
(https://live.staticflickr.com/65535/48523811316_321f94ee7b_o.jpg) (https://flic.kr/p/2gVTdyu)SawOil (https://flic.kr/p/2gVTdyu) by Karl Camp (https://www.flickr.com/photos/160670260@N04/), on Flickr
(https://live.staticflickr.com/65535/48523978677_a2ac3dcebb_o.jpg) (https://flic.kr/p/2gVU5j2)SawOil2 (https://flic.kr/p/2gVU5j2) by Karl Camp (https://www.flickr.com/photos/160670260@N04/), on Flickr
(https://live.staticflickr.com/65535/48523978617_87b83d37d0_o.jpg) (https://flic.kr/p/2gVU5hZ)SawOil3 (https://flic.kr/p/2gVU5hZ) by Karl Camp (https://www.flickr.com/photos/160670260@N04/), on Flickr
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Copper is used to treat some plant diseases and is absolutely deadly to fish and aquatic invertebrates.I have read that it is best to minimize skin exposure.
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Just looked up copper toxicity and it was quite serious for humans .
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I'm not a chemist but oil is used to protect copper from oxidation. I would be more worried about biologics. How does it smell. At the very least I would add a biocide and then filter the oil. Wear a mask.
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My oil did that a couple of years ago, but did so immediately while cutting old Bisbee chrysocolla/azurite/malachite.
First thought was dye, but the slabs showed no typical signs of being dyed. The color never did filter or settle out.
I was also concerned about health risks, but still don't know why it turned that color.
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Here's the link to that old thread:
http://lapidaryforum.net/group/index.php?topic=2183.msg17010#msg17010
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It looks like the deadly water in the Berkley pit in Butte.Almost all the rocks we cut are considered acid rocks as are the rocks that form the pit in Butte. It could have something to do with the ph helping the copper to go in solution.
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I have about 10 gallons of used oil that has never lost the green tint that it picked up after I cut some copper ore. I still use it and filter it as normal oil but it has been green for several years now.
Tony
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Thanks everyone. Glad to hear you had a similar experience Tony. I didn't think I could have been the first person this ever happened to. I will probably just dispose of the green oil.
Its time to clean all the saws anyway so I'm working on finding some oil to change them out. I have been on the phone with people from Idaho to Pennsylvania trying to source some oil locally at a decent price. I have a supplier I need to stop at after work tomorrow, and if that doesn't pan out I may be stuck paying more than I would like. But I'm not messing around anymore with trying to find substitutes. Its white mineral oil or nothing for me. But its amazing what a broad range of "white mineral oils" there are! I've learned quite a bit about them this week.
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Was your criteria for choosing a type the flashpoint?
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I've never really even taken the flashpoint into consideration when looking at coolants for my saws. Although I suppose it is possible I've never actually heard of anyone having a fire or explosion related to oil in their rock saw. Mineral oil just fits the bill nicely. Clear in color. Pretty much odor free. Non-toxic, even food grade if you buy the right ones. Comes in a range of viscosities so you can get it thin enough to even run through a pump easily. Seems to last almost forever (does anyone know what the shelf life of mineral oil is)? I'm sure theres other pluses I'm overlooking at the moment.
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I'm with you on the white oil. Here's what we've been buying locally:
http://www.commerciallubricators.net/sites/commlubricators/uploads/documents/SDS/FINAVESTAN_U_85_NF.pdf
I like the viscosity - it pumps almost like water - and all our saws and blades like it. It has a very slight tint to it, but is still very close to clear.
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So what do you pay for that oil locally? Cheapest thing I can find in my area is around $90 for a 5gal bucket. I can buy what I want for $30 a bucket but I have to drive 7 1/2 hours.
:angry:
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We pay about the same for the Finavestan here in AZ. Only about 30 minutes away from here, though.
That's also what we used to pay for Duoprime 90, but for some reason the price on that went sky-high a few years ago.
Someone said the viscosity of this stuff ( https://www.scahealth.com/scah/product/mineral-oil-light ) is similar, but at $14/gal we've stayed with what we know. With recycling I only buy about 5 gallons a year.
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Finally cleaned out the 18" saw today. Its been running for a few years without a full cleanout...damn what a messy job!! I didn't realize just how thick the layer of sludge was at the bottom until I started the job. But it is spic-n-span inside right now just waiting for new oil. All the old (green) oil and the sludge is straining and I will be interested to see what I get out of it after it has a chance to strain out good. Its going through a pillowcase at the moment, and if its not clear enough I will run it through a paper bag after that. I figure the whole straining process could take the rest of the winter. Its in my shed and out of the way so I can just let it sit. I don't know why I'm bothering with it because I will most likely just dispose of the old oil that has been tainted. I'm just curious to see what I recover from the process.
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Cut some tiger eye, it well turn the green to Orange. Trump Orange.