[jduke]

Seems to me, that Kool mist is essentially a venturi valve to entrain some rust preventative with air to cool the tool.

I am thinking a cheap $15 air brush from HF with some of the solution that they sell should offer some cooling, but would it be enough?

Duke

[DMF_TomB]

you probably could try any paint sprayer that can handle oil and water for coolant. my experience is getting the right ratio as too much water makes rust and too little is a sticky gooey mess.

even if you use straight non detergent 30 weight oil it will help with machining but the fumes from mist is messy and not good to inhale. if you have an enclosed machine no problem, but an open machine maybe easier to use a plastic squeeze bottle and manually apply cutting fluid.

still with air cooling and manually applying oil works , just stand up wind and make sure down wind the fumes won't bother any equipment. computer keyboards and chips /oil covered is not good.

also some people have a skin reaction to coolants. you might want to use disposable rubber gloves. when you want clean hands, it is easy to throw the gloves away and get another pair.

[Mcgyver]

Seems to me, that Kool mist is essentially a venturi valve to entrain some rust preventative with air to cool the tool.

there's a little more to it than that....you're trying to replicate a mist coolant system?

the challenge is getting the right size of droplets so you are not make a fog in the shop. It is possible to have the droplets large enough and going at the right speed that they are actually deposited on the grinding wheel/cutter/whatever but not atomized fine enough the entire shop becomes a heath hazard. that's what does the cooling, not so much a blast of air. A great way to do it is pressurized coolant (water soluble coolant not just oil or rust inhibitor) and air with separate regulators. dimensions of mixing block and nozzle become important

there is a bunch of how to material on practical machinist and home shop bbs describing the diy construction of successful systems

[Karl_T]

I made one of the first.

See this thread for info

http://groups.google.com/group/rec.c...uthor:townsend

[jduke]

I made one of the first.

See this thread for info

http://groups.google.com/group/rec.c...uthor:townsend

I followed the link, and that sounds like exactly what I am looking for.

the links to pictures from your post didn't work, do you have any pictures that you could post here?

from your measurements, it sounds like the HVLP sprayer would just fill the shop with fog rather than provide a cooling mist.

Thanks
Duke

[Al_The_Man]

See the last files on the list.
http://www.metalworking.com/dropbox/...retired_files/
Al.

[Karl_T]

I followed the link, and that sounds like exactly what I am looking for.

the links to pictures from your post didn't work, do you have any pictures that you could post here?

from your measurements, it sounds like the HVLP sprayer would just fill the shop with fog rather than provide a cooling mist.

Thanks
Duke

Looks like the web master there organized a bit. Go to the bottom of this page.
http://www.metalworking.com/dropbox/...retired_files/

[wildwestpat]

Hi folks

This may be a bit off beam but I have just come in from spraying the roses and wonder if the common garden sprayer would be a quick way of achieving a mister? I don't have - as yet - an air compressor hence the question. Obviously a new clean sprayer would be needed as the 'roses' would die if sprayed in oil and I might die if the residue of the bug spray is still in the one used in the garden - hence I would need a new one for CNC.

Guess the day is fast approaching where I invest in a compressor - currently these are about four times the price of a garden sprayer. Just need to convince my wife as a compressor is too big and noisy to kreep in via the back gate!

Thanks Al for the link to the mister hope to read reports that the design is good. The drawing and the picture are just the ticket for a home brew.

Good luck at dispelling the fog.

Regards

Pat

[Al_The_Man]

Thanks Al for the link to the mister hope to read reports that the design is good. The drawing and the picture are just the ticket for a home brew.

I am just in the process of putting one together, I used the idea from Karl_T design for a propane tank for the coolant, but I am taking a slight different approach with the piping, without the need to drill the tank, I will post the results if it works out.
Al.

[wildwestpat]

Hi Al

I just knew you would not let us down. Experiment is rocket fuel for the mind.

Hope you achieve a good result.

Regards

Pat

[Al_The_Man]

I finally got the FogBuster together, it is based on the one built by Karl_T.
I used as much as possible from parts on hand, The local pnumatics dealer had regulators on sale so It cost around $60-$70 all in.
The expired tank I got for free.
I used a flexible pipe for the coolant in the tank, this allowed me to use the 3/4" pipe opening for the only entry into the tank, it is also used for filling.
I had a the chrome flexible coolant pipe with magnetic base on hand from previous coolant system.
I tapped the end out for a MIG nozzle, which was around .040" dia.
The air is switched on via a pnumatic valve that can be controlled directly from a supply 120v socket or 24vdc depending on what you use, or from the machine itself if an external socket is mounted on the enclosure that houses the CNC.
What I did not consider was the final weight when the unit is full it weighs almost 70lb.
For now I have a dolly to move it, later I will put castors on the bottom.
Al.

[wildwestpat]

Hi Al

Have you - or - anyone else - a ball park figure for the air consumption of this type of device. I have a little air brush compressor that gives arround 3/4 cu ft per minute free air and is capable of 30 to 40 psi but all you guys appear to have 7 cu ft + compressors. I still do't fancy the din of a garage type compressor hence the question.

Thanks for the pics and the refference to the origional - you are begining to make me see there is more to cooling than a simple flood system.

Regards

Pat

[Karl_T]

Hi Al

Have you - or - anyone else - a ball park figure for the air consumption of this type of device. I have a little air brush compressor that gives arround 3/4 cu ft per minute free air and is capable of 30 to 40 psi but all you guys appear to have 7 cu ft + compressors. I still do't fancy the din of a garage type compressor hence the question.

Thanks for the pics and the refference to the origional - you are begining to make me see there is more to cooling than a simple flood system.

Regards

Pat

Mine don't use much air but I got no measurement. Use it only when cutting and you should be fine.

[Karl_T]

Hi folks

This may be a bit off beam but I have just come in from spraying the roses and wonder if the common garden sprayer would be a quick way of achieving a mister? I don't have - as yet - an air compressor hence the question. Obviously a new clean sprayer would be needed as the 'roses' would die if sprayed in oil and I might die if the residue of the bug spray is still in the one used in the garden - hence I would need a new one for CNC.

It would work but a couple issues. You get much larger droplet size and much higher flow rate. I adjust mine to maybe 2 gal/hr run time. Can set it to much less. Most spray nozzles would be in the range of 30+ gal/hr. How do you keep refilling the tank? And you need all the guarding for flood.

Karl

[wildwestpat]

Hi Karl

Many thanks - good point about the quantity of fluid used by a modified garden sprayer. I am interested in gear wheel cutting so the run length is less than 30 minutes. But it looks best to bite the bullet and go with a proper mist cooler now that the design has been cracked and reduced to a home made device for our own use.

Need to raid the scrap box for the materials and get going. Thanks to all contributers to this thread for providing the push to progress from flood / WD30 aerosol practice!

Kind regards

Pat

[kanton]

Al,

Could you provide a parts list or at least some idea of what type of regulator and compressor is needed for this rig?

Thanks

[Al_The_Man]

I have a 2hp twin piston that is about 15cfm, I am not sure what the minimum could be, but I would say 10cfm min.
The adjustable regulators are standard pneumatic 0-150lbs 1/4 or 3/8 input, these particular ones were 3/8 on sale, the rest is fittings and tubing I had kicking around.
Those quick disconnect fittings are neat, just push them together and they seal, they even use this principle for auto gas lines
The pneumatic needle valve was surplus off equipment I had picked up.
I used a small MAC N.C. air valve to switch it on when required.
And of course, an expired propane tank.
Al.

[kanton]

I will begin this post by stating that I know very little about airbrushes or mist cooling.

If I were cutting metal on a CNC Seig X2 would it be possible to use a modified compressor and airbrush kit as a mist cooler? For example, if you modified this Harbor Freight Airbrush Kit by attaching a larger liquid container and aimed the nozzle at the cutting area would this be enough?

Link to Harbor Freight Airbrush Kit : http://www.harborfreight.com/cpi/cta...emnumber=95630

[Al_The_Man]

For any shop compressor you need to add a reservoir tank, these small diaphragm compressors are intended for small dedicated low CFM applications.
These would be OK for constant air flow, but would not keep up with fogbuster type coolant system.
Al.

[Steve Seebold]

I have been using the Hench FogBuster since 2004. They are absolutely the best mister I have found to date.

I pressurize the tank with 40 PSI and I pressurize the nozzle with 6 to 10 PSI.

There is not much mist coming from the nozzle. Actually, if you can see the mist, that's too much.

I have the 1/2 gallon dual nozzle mister on all 3 of my machines, and that amount of coolant will last about 2 weeks when I work about 6 hours a day.