Kool Mist Problems

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mechanicalmagic
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Kool Mist Problems

Post by mechanicalmagic » Thu Jul 16, 2009 10:11 pm

I used Kool Misters for a few decades at work, neat thing. So, when SWMBO wanted to buy me a present, 7-9 years ago, I thought that would be a good thing for the mill.

It was never right.
First off there was a narrow adjustment for the vacuum, suck just fine one place, no vacuum a half turn away. So, I used an automotive vacuum gauge to adjust to the best vacuum, and made a spacer. Pict #1.

If it needed to draw coolant uphill, it took FOREVER. So I mounted the tank above the spray nozzle. But now it was a siphon, so I added solenoids connected to the spindle motor. Pict #2. (My apologies, the forum software doesn't like the rotated picture.) But now it spits. So, I added a coolant valve, Pict #4.

Sometimes I don't use the thing for well, months. It gets plugged up with gunk, so I added a filter. Pict #2, but it never seemed to gather any junk. But it was still getting plugged up. Recently I took the whole thing apart, and found gunk in the blue block, input side for the coolant. It was full of crap. Pict #3. As you can see, the anodize is gone, something has attacked the threads and internal surfaces. Fine, clean it out and it'll be good for a few months. Wrong, next week, it's plugged again, right when I need it most.

Having reached the end of my patience, I decided to figure out what the heck was going on. The only place clogging was in the Aluminum block, at the joint between the Brass fittings and the Aluminum block. Looking at the work function between Aluminum and Brass (Cu, Pb, Zn) it's obvious there is a potential for galvanic corrosion problems. My solution was a see thru block made from Lexan. Pict #4. Notice the extra vlave to control the coolant, sticking straight up.

Finally I have good control over the amount of air, and coolant, at one time. Don't know if it will work for the long term, but I like it now.
If anybody wants the drawing of the block, I can email it to them in several formats.

Dave J.
Attachments
Spacer.JPG
Spacer to set max Vacuum
Reservoir.JPG
Tank with Solenoids and Filter
OldBlock.JPG
Corroded Kool Mist block
Block.JPG
Lexan block with Valve
Every day I ask myself, "What's the most fun thing to do today."
9x48 BP clone, 12x36 lathe, TIG, MIG, Gas, 3 in 1 sheetmetal.

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JimGlass
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Post by JimGlass » Fri Jul 17, 2009 6:33 am

Good idea you have there.

Years ago I bought a spray mister on Ebay. Someone was making and marketing them for $20. I had to tinker with it to get it to work but finially did. It seems like it took a lot of air to work.

Someone gave me the idea of a drip coolant system which I made and still use today. It uses less air and droplets of coolant are dripped over a small steam of air where the air propels the coolant to the tool.

Image

I used a 2" pipe nipple X 18" for a tank. At the top is an air regulator to pressurize the tank and push coolant out the bottom via a few pounds (5 psi) of air pressure.

Below is the coolant delivery tubes. The top hose carries the coolant and the lower hose is the air. I used square brass tubing (From Lowes) soldered to the a brass mounting block. The ends of the brass tubes are held togeter another piece of round brass. There is no nozzle with this system.

Image

Not shown in the pic are two flow control valves, one to regulate coolant and another to regulate air flow.

Below is the system working.

Image

Notice there is no coolant fog. Coolant is dripped from the top tube and air from the lower tube propels the coolant.

I made this system to use on my CNC Bridgeport retrofit for applying WD40 when machining aluminum. I can run all day on a quart of WD40.
From the CNC program I start and stop the coolant application as needed.
There is such a small amount of coolant used it is absorbed by the chips so there is no coolant recovery required.

Jim
Tool & Die Maker/Electrician, Retired 2007

So much to learn and so little time.

www.outbackmachineshop.com

Black_Moons
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Post by Black_Moons » Fri Jul 17, 2009 8:19 am

Love the see through block, you can finaly tell when its getting cloged heh.

Jim: Thats a great cooling/lube system! praticaly like spreading it on with a dropper can or brush, just enough deposited RIGHT where you need it in drops too big to go anywhere/everywhere else.

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JimGlass
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Post by JimGlass » Sun Jul 19, 2009 9:50 am

Thanks,

Ya, it saves compressed air as well and most of the coolant goes to the tool instead of everywhere else.

Jim
Tool & Die Maker/Electrician, Retired 2007

So much to learn and so little time.

www.outbackmachineshop.com

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Mid Day Machining
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Location: San Clemente, CA

Spray coolant

Post by Mid Day Machining » Sun Jul 19, 2009 11:49 am

There is a spray mister called a Fog Buster. It is made by Hench Mfg. in San Clemente, CA. I use one on my Dyna-Mite mill and I only use about a quart of coolant a week. I put 40 psi in to the mister, and then regulate it down to 6 psi out. The 6 psi pressurizes the tank and pushes the coolant out, then I can regulate flow at the nozzles.

keith524
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Re: Kool Mist Problems

Post by keith524 » Thu Nov 22, 2012 1:44 am

hey can i get the drawings of the coolent block? and where could a man buy the hose's that have the hose inside of the hose for the air/water mix? my email is keithirwin35@gmail.com thanks so much!

RSG
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Re: Kool Mist Problems

Post by RSG » Fri Nov 23, 2012 8:35 am

Fantastic fix MM, it's gratifiying to get to the root of a hidden issue!

Not to hijack the thread but a quick question pertaining to the use of those types of systems - Do you wear a mask when using it? I'd imagine the vapours would be very toxic? They look a whole lot cleaner than a flood coolant system.

RG
Vision is not seeing things as they are, but as they will be.

Joe Gwinn
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Re: Kool Mist Problems

Post by Joe Gwinn » Sun Nov 25, 2012 4:26 pm

RSG wrote:Not to hijack the thread but a quick question pertaining to the use of those types of systems - Do you wear a mask when using it? I'd imagine the vapours would be very toxic? They look a whole lot cleaner than a flood coolant system.
It is a real problem. My shop would have a visible fog bank after a machining session, and I had to wear a 3M filter mask, or spend the next day coughing. I no longer use the mister, instead using flood or dribble cooling (of oil emulsion).

Joe Gwinn

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