Advice needed: Low maintenance coolant for small shop, with big equipment.

javand

javand

Joined
Oct 17, 2010
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Since I'm doing an unusual amount of drilling and cutting lately, it's got me back on a mission to figure out the proper coolant solution for my shop.

Currently the only machine I'm using pumped fluid to is my Startrite Horizontal bandsaw. I'm using Mobilcut 421 soluble cutting fluid in it. Unfortunately, with evaporation, and low use (a few cuts a day usually, unless I'm cutting up bar stock, but lately I'm getting it sheared anyway), it doesn't seem to be holding up great.

I've got a large tank and pump that goes with the surface grinder, which I'm not using yet, but i'd eventually like to be using flood to it, the larger drill and my mill. I plan on adding a full sized lathe this year also.

I'm wondering if I can't just set up a distribution system from this single tank, although I can set up seperate systems if needed. Most importantly, I'm looking for advice by those with first hand knowledge, what my best option for a low maintenance, long lasting coolant/cutting fluid option is for a low volume shop like mine. Soluble, oil, synthetic, semi synthetic, etc?

Most of the info on the machinist forums seems to come either second hand, be based on brand loyalty, or from high volume shops that specialize with one type of material. I'm mostly working with various steel and aluminum, but also some bronze, brass, copper, etc.


So what's my best general option, can I use one solution for all machines? What else do I need to consider? Any help is greatly appreciated.
 
This is a good question. I don't know the answer.

From my personal experience, I've had good luck with sump life using Trim Microsol 585XT semi synthetic. I have six wet sumps right now, some of which sit for months at a time and I haven't had any funk since master chemical reformulated the 585 into the new XT version a couple years ago. And it stays soft when it drys, not hard or sticky. No rust and no sump livers. Smells like cake batter. I skim it regularly and use a refractometer to keep the concentration in the correct range and I've never had any problems with it. I'm sure the same can be said of other quality formulations.

I'm not sure it plays nice with copper.

I've been considering consolidating coolant simply to decant it to remove micarta fines and skim the oil.
 
Ntathan, I was hoping you would chime in.

Are you using this same coolant for all cutting tasks? I can get by with doing the marginal amount of copper dry, if that's the primary trade off. Although Grainger's info lists it as copper compatible.

Is this diluted with water ,and if so, when adjusting concentration can you add water straight to it without issue? Do you need to monitor ph?


Thanks Nathan, I'm probabaly going to give this a shot. I've got a ph meter but need to pickup a refractometer.
 
You don't need to monitor PH unless you're machining something like PVC or other materials that can lower the PH. Once the PH gets down around 8.0 you can start getting rust. I had to machine a few tons of PVC a couple years ago and got a PH meter but haven't needed it in a long time.

It is used between 5 and 10%. This works out to something like 4 to 8 on a brix scale. I keep it above 5 brix and never have any rust.

You can add water directly to a sump if it has condensed. You can not add oil directly to the coolant. In fact, you'r not even supposed to build make up with coolant from the sump, you're supposed to use fresh water. Something about the micro emulation and the water in the sump already attached to tramp oil will prevent a stable solution and you lose it. When you mix it, you put clean water in a bucket and get somebody to stir while you add the coolant concentrate.

I've never seen it get funky in a sump. You know how an oil skimmer pulls out about as much coolant as it does oil? I had an old bucket of coolant with a cap of oil on it sit in the shop for months. With the oil cap it should have been nasty with anaerobic bacteria but I pulled the oil off for disposal and the coolant on the bottom looked and smelled okay so I put it in the bandsaw. (disclaimer, I hate that bandsaw)

It was designed for machining cast iron and titanium, but after a little research I eventually settled on it for some high volume plastic work. It has a good operator safety history and cleans off of parts with a water rinse. I get good finishes in aluminum and steel and even roll form tap with it. I use it on the saw, mills and lathe. I don't know how it will do on a grinder. I actually just did some grinding with it for the first time this afternoon. I'm not sure how compatible it will be with stones in the long term.
 
I've (admittedly) never seen anybody or had a need myself for coolant on a surface grinder. Usually not doing production grinding/heavy stock removal when using it. You can usually get away machining dry with the right speeds and feeds as a home shop user. However, I would want some coolant/lubricant with a lathe (I'm a mill guy, and can use all the help I can get when turning stuff). I would just get some cheap soluble oil from Enco, to use on all your applications, and a cutting/tapping fluid (Moly-dee, although since the crazy price increase, look for something cheaper) for reaming/tapping.
 
Thanks Nathan, I'm going to give it a shot.

Dan: I get what you're saying, and I've tried to get by that way, but I do tend to find myself doing bigger wierder stuff than the average home shop. I've got some big gear for a home shop. Big 7,000lb K&T mill, Landis Hydraulic Feed Surface Grinder, a couple of big saws, plans for a fairly large engine lathe, and a universal grinder.

Last week I was sawing and boring 6x6 A2 for instance. Not huge, in the scheme, but not something I can dry cut, and I keep heading in the direction of bigger and bigger work. So, this is an issue I'm feeling compelled to address.
 
javand,

Props on your collection of cast iron, plus the work to go with it! You may be best served talking to a local distributor then for coolants. Castrol,etc.

Congrats on the work. I know what you mean about bigger and bigger work. I have pretty much specialized in big work the past couple of years. All my mills/routers I run have 144" travels X and pretty close in the Y.
 
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I know I'm bringing this back from the dead but I was wondering how you guys dispose of the 585XT in a safe manner...? looking for exactly all the benefits of this stuff but yet it be biodegradable or something easy to dispose of when done.

Edit: also I have a few more questions:

1. I see that I need a refractometer to measure accuracty of this during use, any recommendations on something that will work decent price range?
2. I have looked up instructions but can't seem to find mixing instructions... do you just gauge this w/ the refractometer until you are in the right range?
3. How much will 1 gal make of coolant suitable for grinding (estimate)?
4. What do you use to filter and recycle this stuff? Or do you just drain it into a seperate bucket and toss when used?

Thanks guys. Great thread!
 
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Since this thread is back from the dead do you guys still like the Trim Microsol 585XT or have you moved on to something else?
 
Not sure Nathan is still using it but I am. Very happy with it.

I moved my shop about a year ago and replaced the coolant in my saw sump, but other than that, I just add make up solution when it gets low enough to need it. I never test it with a refractometer.

It's probably not ideal this way but for my use is fine. The mills get a little more attention, but pretty much the same ease of maintenance. Stuff stays stable pretty much no matter how long I neglect it. Only issue is getting waste oil from other processes mixed in and having to skim. That's an issue with any.

Overall I'm very pleased with the product, and thankful to Nathan for recommending it.

1 gallon mixed at 10-20 to 1 produces a lot of coolant for small sumps.
 
We use it at 5-10% so 5 gallons is good for 50-100 gallons of coolant.

We never discard the stuff. We use oil skimmers to pull the tramp oil off the top of it. That get decanted, the oil pulled off and recycled and the coolant goes back in.

Most people don't need to filter their coolant, but if you're cutting a lot of G10 and micarta you will. Our sumps are set up for continuous filtration, but just occasional use you can use a centrifugal pump and a sock filter to pump your sump out into a garbage can then clean out any chips in the sump by hand then pump the coolant back into the sump. This is called mucking the sump and needs to be done every few years.
 
javand said:
Not sure Nathan is still using it but I am. Very happy with it.

I moved my shop about a year ago and replaced the coolant in my saw sump, but other than that, I just add make up solution when it gets low enough to need it. I never test it with a refractometer.

It's probably not ideal this way but for my use is fine. The mills get a little more attention, but pretty much the same ease of maintenance. Stuff stays stable pretty much no matter how long I neglect it. Only issue is getting waste oil from other processes mixed in and having to skim. That's an issue with any.

Overall I'm very pleased with the product, and thankful to Nathan for recommending it.

1 gallon mixed at 10-20 to 1 produces a lot of coolant for small sumps.
Click to expand...

Nathan the Machinist said:
We use it at 5-10% so 5 gallons is good for 50-100 gallons of coolant.

We never discard the stuff. We use oil skimmers to pull the tramp oil off the top of it. That get decanted, the oil pulled off and recycled and the coolant goes back in.

Most people don't need to filter their coolant, but if you're cutting a lot of G10 and micarta you will. Our sumps are set up for continuous filtration, but just occasional use you can use a centrifugal pump and a sock filter to pump your sump out into a garbage can then clean out any chips in the sump by hand then pump the coolant back into the sump. This is called mucking the sump and needs to be done every few years.
Click to expand...

Thanks for the input guys. Well I am using it for wet grinding and the problem w/ that is that the coolant has to be super clean... so any ideas on filters? Something as fine as a coffee filter would probably be good. I am thinking about filtering the exhaust coolant before it goes back into the bucket. right now I have suction from one bucket and exhaust into a separate one and toss that when it gets full. I suppose I could do the same thing w/ this as it is not that expensive w/ the dilution ratio, but it may save even more $ to just filter.
 
I'm gonna resurrect this thread again, to mention that I was looking for coolant recommendations for my surface grinder and managed to unearth this little jewel of info. Thanks Nathan! I'm gonna buy some too.
 
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