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Boucher
07-04-2009, 12:36 PM
I see references to coolant going bad fairly frequently in different threads. There are even aerators being advertised recently to prevent this problem. I have never had this happen. My system is unused for long periods of time. I use Rustlick 5050 and Ashburn 9000. Is this like the pilot that flies retractable aircraft landing with the wheels up. There are those that have, those that will and those that will again. Is it just a matter of time before I experience this first hand ? What is going on ?

Mcgyver
07-04-2009, 12:51 PM
just be glad. its my understanding that they are all oils in one form or another and eventually bacteria will feed on them. As the bugs don't like oxygen, I use fish tank aquarium aerators in each tank after i had a tank of cooltool go bad....ask me in six months how well its working.

Rich Carlstedt
07-05-2009, 03:07 PM
You don't want organics in the tank.
A common problem in machine shops, because guys eat at the machine, or spit in the sump ( yeah, I know)

I have had my soluable oil in my mill for----9 years.
Same oil.
I add water due to evaporation and some new oil when the level gets low.
The secret is simple.
I have a black light ( UV bulb)
I skim the tramp oil (way lube) off the top and exposed the coolant by placing a UV light in the sump,
and I force the return to waterfall over a screeen into the sump so all the coolant gets exposed.

You need to protect your eyes from seeing the bulb, and prevent the coolant from splashing on the
hot bulb which will explode.

Coolant providers don't tell you that UV kills all bacteria.. they would loose sales
Without bacteria, no odor and as we know, oil never wears out.

Rich

bobw53
07-05-2009, 03:52 PM
My theory, and that of Blaser is that you are not looking to kill all bacteria, but to have a bacterial balance, where they eat each others excrement, much like a fish tank.

Pretty simple, going on two years with some sumps in the shop now, the only time I've run into problems is when the concentration gets low and then it just
gets a bit musty, and some of the sumps occasionally sit for weeks at a time.

I'll definitely agree with keeping the organics out, sunflower seeds, tobacco spit, leftover coffee, urine, sawdust. You can also get into trouble playing amateur chemist, best to stick to a quality coolant. If you can order up a drum of coolant, some floor wax and a case of toilet paper from the same company, I'd stay away from it.

Quick story, a friends sister was doing an internship at a large manufacturer. They had huge coolant stink problems, changed brands, all kinds of analysis, nothing worked, still huge amounts of rancid coolant. Finally had a detailed analysis done. The culprit, semen, seems somebody on 3rd shift was really excited about their job.

websterz
07-05-2009, 04:32 PM
My theory, and that of Blaser is that you are not looking to kill all bacteria, but to have a bacterial balance, where they eat each others excrement, much like a fish tank.

Pretty simple, going on two years with some sumps in the shop now, the only time I've run into problems is when the concentration gets low and then it just
gets a bit musty, and some of the sumps occasionally sit for weeks at a time.

I'll definitely agree with keeping the organics out, sunflower seeds, tobacco spit, leftover coffee, urine, sawdust. You can also get into trouble playing amateur chemist, best to stick to a quality coolant. If you can order up a drum of coolant, some floor wax and a case of toilet paper from the same company, I'd stay away from it.

Quick story, a friends sister was doing an internship at a large manufacturer. They had huge coolant stink problems, changed brands, all kinds of analysis, nothing worked, still huge amounts of rancid coolant. Finally had a detailed analysis done. The culprit, semen, seems somebody on 3rd shift was really excited about their job.

Some things you wish you could go back and UN-read...:eek:

Mark Hockett
07-05-2009, 05:35 PM
The secret is simple.
I have a black light ( UV bulb)
I skim the tramp oil (way lube) off the top and exposed the coolant by placing a UV light in the sump,
and I force the return to waterfall over a screeen into the sump so all the coolant gets exposed.

Rich

Rich,
Can you elaborate on the black light? Size and spec of bulb, where its mounted and maybe a picture. Do you leave it on all the time?
I have a skimmer, aeration pump and my return coolant goes over a waterfall on to a screen but I have never tried the UV light. I just got a 55 gallon drum of coolant with an automatic mixer and was going to change out all my machines this week. I would like to try the UV bulb too because changing out coolant in my shop is a real pain in the a$$, the VMC alone holds 40 gallons and the tank is buried.

I also wonder if this would work on my anodizing dye tanks as bacteria can be a huge problem with them.


The machine shop I use to work in busted one of the night guys pissing in a machine another guy was operating.

Rich Carlstedt
07-06-2009, 03:03 PM
Mark here are a couple of photos

The light bulb is a GE 60 watt Black light.
My spare is shown in the photo
Costs 3 bucks at Walmart.
The light in the bucket is a 25 watt that I put in just for the photo, as the black light was too dark for picture taking.
When starting up and planning to use the coolant, I check it , clean the tramp oil, and then start circulation and the light.
You could run it all the time, but eevaporation is the issue there. the bulb does get VERY hot and that may add to the problem.


The setup I have is super simple.
After almost dying from cleaning out a soured machine sump (3 years of bacteria growth -no use) on a mill I bought, I made things simple.
I use a 6 gallon bucket, some PVC fittings, a Garden pump, a half gallon plastic bucket, and some 'knee high stockings" (box of ten for 3 bucks)
The garden pump sits inside the plastic pail at the bottom of the bucket.
This prevents 'fines" from being sucked into the pump.
The pump is the white object hidden by the near wall of the bucket.
My Mill table is screened. Return coolant travels down two tubes into the permanent elbows at the top of the bucket.
I tie off a stocking with twist wrap over the downward facing elbows.
It is that stringy thing behind the electric cord
The stocking acts a a filter screen and because it has a natural tendency to narrow, the chips stay inside and the coolant is forced to the outside surface where it is exposed to light. When the sox gets heavy with chips, I pull it out and let it drain , then toss it. clean and easy, as a new one is put in its place. Very cheap clean up for a super fine mess screen !
If you look in the middle of the picture, you see the pressure line from the pump with coolant still in it.
This clear tube also exposes the coolant to light.
I have not used the mill for a bit, so the tramp oil is still on top.
When I don't plan to use the mill for awhile, I drain off some coolant into a storage container. The pail is coverecd when not in use
The light bulb is turned on when I start the mill up and the soluable oil is stirred to check on condition. when it settles down in a few minutes, I skim the tramp oil off and adjust the light fixture which clamps to the side of the bucket.. I leave the light on about 80 percent of the time the coolant pump is running. One time after a long hospital stay, I started it up and the coolant was pink. I turned the UV light on and after an hour of circulation, the color was tan again.
The light should not be looked at and the splashes are minimal from the sox filter.
This technique is used by many labs. They generally flood a tube of liquid (like my pressure line) with UV to stearalise the liquid.
I preffer the sox idea as it exposes more coolant and a tube can become opaque over time.
The 60 watt is WAY overkill.
If I ran the system all the time, I could do the same work with 10 watts. but it works......and that is the important thing.

Rich
Sorry for the long post


http://i273.photobucket.com/albums/jj220/StationarySteam/Shop%20Tools/P7060002.jpg

http://i273.photobucket.com/albums/jj220/StationarySteam/Shop%20Tools/P7060001.jpg

Quetico Bob
07-06-2009, 03:12 PM
QUOTE
A common problem in machine shops, because guys eat at the machine, or spit in the sump ( yeah, I know)
QUOTE

Don’t forget, “man do I have to take a leak”

Have never have a problem with mine, 2 years same sump. Just maintain levels, reduce as much air exposure to the surface as possible and diligently skim the way oils.

Cheers, Bob

Mark Hockett
07-06-2009, 11:17 PM
Rich,
Thanks for the explanation, I will definitely try it. I have known about the nylon trick for a while. My machine has long channels that the coolant flows down to get back to the tank. The nylons fit around the ends of the channels and sit on the screens that are on top of the tank. They really help keep chips from getting in the tank and plugging up the screen.