# No Fog Coolant Mister



## Terrywerm (Jan 5, 2014)

The plans listed below are for building your own no fog coolant system to use in your shop. Compressed air is required, but the design will apply coolant to your cutting tools without creating a foggy mist in the air when it is used properly. In practice, the air volume is turned up just enough to gently blow chips away from the cutting area, which will also carry small droplets of coolant to the tool. 

Most dimensions can be changed without issue, however there are two dimensions that are critical: the .040" hole in the mixing block, and the .040" hole in the nozzle.  The air passage through the mixing block must be large enough to slow the speed of the air flowing through it, but must be small enough for the air to travel fast enough to carry the droplets of coolant along.

I made my mixing block from brass for three reasons, but aluminum could be used: 1. I like the look of brass    2. It was what I had   3. Allows assembly by soldering if desired

The drawings show using only one regulator on the system, but two can be used, providing different pressure settings for the mixer air and for the fluid reservoir. 

This coolant system could be used with any light coolant, such as Kool Mist, WD-40, or even soluble oil. Heavy cutting oils will most likely not work well with this system.

The drawings and bill of materials depict the system as I am currently building mine. If it becomes necessary to make changes to a drawing, I will do so and post the revised drawing here, replacing the original, then will post a note to the thread. As always, some individuals will do some things differently, and that is okay.

Comments and ideas are welcome, let me know what you think.


View attachment NO_FOG_MISTER_001.pdf

	

		
			
		

		
	
   - Coolant system overview
View attachment NO_FOG_MISTER_002.pdf

	

		
			
		

		
	
   - Regulator and air fittings         
View attachment NO_FOG_MISTER_003.pdf

	

		
			
		

		
	
   - Reservoir and fittings
View attachment NO_FOG_MISTER_004.pdf

	

		
			
		

		
	
   - Reservoir modification details  
View attachment NO_FOG_MISTER_005.pdf

	

		
			
		

		
	
   - Mixer head assembly              
View attachment NO_FOG_MISTER_006.pdf

	

		
			
		

		
	
   - Mixer component details in English/Imperial measurements        
View attachment NO_FOG_MISTER_006M.pdf

	

		
			
		

		
	
   - Mixer component details in Metric measurements
View attachment NO_FOG_MISTER_007.pdf

	

		
			
		

		
	
   - Bill of materials


ON EDIT:  I discovered an error on one of the drawings regarding the nozzle size, and it has been increased from .040" to .090" and it works much better at this size. Alternatively, the nozzle could be eliminated and the coolant could exit directly from the extension tube. 

All drawings have been updated as of 1/11/2015


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## wrmiller (Jan 5, 2014)

Thanks Wermie! Already downloaded and queued for one of my next projects.  

Bill


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## bpratl (Jan 6, 2014)

Thanks again for a great project, design and layout.
Parts are now on order.


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## yohan (Jan 6, 2014)

Brilliant Idea! something I will be trying out shortly

Thanks for Sharing!

Johannes


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## Chucketn (Jan 6, 2014)

I also downloaded and printed the plans and the No Fog Mister is on the to do list. Thanks for sharing Terry!

Chuck


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## Terrywerm (Jan 6, 2014)

For those who work in the metric system and have already downloaded the plans, go back to the initial post in this thread, as I have added a metric version of drawing 6 which contains all of the critical dimensions. Sadly, not everything converted over correctly, but most things did. It should make things easier for you anyway.

One other thing: I mentioned assembly of the block by soldering if desired. After giving things more thought, I think it would be a good idea to thread the block, extension tube, and nozzle for assembly. This would allow disassembly in the event of foreign material getting into the mixer and plugging it up. Cleaning it all out would be much easier if it can be disassembled.


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## melsdad (Jan 14, 2014)

Thanks Wermie! This looks like a great project. The drawings and parts list are top notch!


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## LJP (Jan 14, 2014)

Nice set of drawings! Simpler than I thought it would be to make. Thanks


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## TomS (Jul 2, 2014)

terrywerm said:


> The plans listed below are for building your own no fog coolant system to use in your shop. Compressed air is required, but the design will apply coolant to your cutting tools without creating a foggy mist in the air when it is used properly. In practice, the air volume is turned up just enough to gently blow chips away from the cutting area, which will also carry small droplets of coolant to the tool.
> 
> Most dimensions can be changed without issue, however there are two dimensions that are critical: the .040" hole in the mixing block, and the .040" hole in the nozzle.  The air passage through the mixing block must be large enough to slow the speed of the air flowing through it, but must be small enough for the air to travel fast enough to carry the droplets of coolant along.
> 
> ...



After searching this forum on coolant delivery systems I came to the conclusion that flood and misting, while having good points, also have negatives that led me to your post on no fog cooling.  I liked the concept and decided this is the way I wanted to go.  Most of what I did was as described in your post and drawings.  I made a few changes mostly because parts and material were on-hand or could be purchased locally.  The following pictures show my installation.  

What troubles me is I can't get a steady flow of droplets.  I've varied the air pressure from 3 psi to 60 psi and adjusted the needle valves and either it intermittently spits out coolant or I get a steady stream of liquid out of the nozzle.  Tried it both with one regulator as shown on the drawings and with two regulators; one controlling the air pressure to the nozzle and the other controlling the air pressure to the filter housing.  The pressures are extremely sensitive to adjustments.  Is this normal? What pressure should I run at?  It's flowing way too much coolant and empties the filter housing in about three minutes of run time.  I'm missing something but can't put my finger on it.  Any help is appreciated.

Tom S




Photo 1 - Picture of the metering block.  The upper left needle valve is the air feed to the nozzle.  The nozzle is fed by the clear Tygon tube that loops down and under the metering block.  The bottom needle valve is fed from the outlet of the filter housing.  The metering block is drilled and tapped 1/8" NPT for the needle valves with a .040" diameter hole in the nozzle feed circuit. 




Photo 2 - Picture of the regulators.  The black hose is the air feed to the filter housing.  The left regulator is plumbed into a pipe tee that is not visible in the picture and is plumbed to the metering block.




Photo 3 - Not a good picture.  The nozzle tip has been fitted with a brass plug with a .040" diameter hole in it.




Photo 4 - Picture of the filter housing plumbing.  The black hose comes from the right hand regulator shown in Picture 2.  The 1/4" nylon tube on the outlet side of the housing feeds the lower needle valve on the metering block.




Picture 5 - Another picture of the metering valve plumbing.


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## Terrywerm (Jul 3, 2014)

Tom,

I would first try enlarging the hole in your nozzle, it's size is not so critical as the .040" hole in the mixing block. You might even try removing the nozzle. Once you've done that, you can use more air flow to carry the small droplets to the work. 

What is happening right now is that the air starts to carry the droplets at the mixing block as it is travelling at a velocity high enough to do so. Once the air/coolant stream hits the large inner diameter of your flex hose, the velocity is greatly reduced and the fluid droplets drop out of the slower moving air. Once the liquid forms a large enough 'puddle' in the flex hose, the air pushes all of it out at once. You also might be opening your fluid needle valve too far due to the perception that there is no coolant coming through. 

The original design called for a straight nozzle that is relatively short in length, and small enough in diameter to keep the air velocity high enough to still carry the droplets, but not so high that the droplets become atomized, thus not creating a fog in the room. The flex hose you are using may be what is causing the problem.

I made a prototype that worked reasonably well, but it was a bit bulky. The mixing block was too large, as were the needle valves that I used in the first design. The design in the drawings is a smaller version of that prototype, and I still need to build one of the smaller ones. The needle valves are sensitive, especially if they are overly large, but the sensitivity is not as bad at lower pressures. You should only need about 20 PSI at max, maybe a hair bit more, but probably less in most cases. You are looking for air volume, not pressure. A higher volume stream, at lower pressures, can carry tiny droplets of fluid in the air stream. Air will provide most of the cooling, aided by the cooling effect of a tiny bit of fluid. 

In use, you should turn on the air first. Get a nice flow going at a lower pressure, but not so much flow that it gets real noisy. Next, just crack the fluid valve open a tiny bit while holding a finger out ahead of the nozzle. When the fluid starts coming, you may not see it, but you will feel it as the temperature of the air stream will drop sharply. If you watch closely you will see that your finger is starting to get wet, but not dripping wet. That is all you need. One canister of coolant should last for several hours, as in all day or more. Granted, a heavier milling job will need a bit more coolant, but you will be surprised at just how little it really takes. 

Fiddle with your modifications a bit, then come back and let us know how you've done. Feel free to tell us what works and what doesn't, and don't be afraid to critique my design if you find a flaw with it, even if it is only a personal preference. I am going to be out of town for a couple of weeks, but will check back here when I return.


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## TomS (Jul 3, 2014)

terrywerm said:


> Tom,
> 
> I would first try enlarging the hole in your nozzle, it's size is not so critical as the .040" hole in the mixing block. You might even try removing the nozzle. Once you've done that, you can use more air flow to carry the small droplets to the work.
> 
> ...



Wermie,

Thanks for your explanation and suggestions.  I've got a kitchen remodel in progress so may not be able to get back to the coolant system for a few days.  But I will post what I did and the end results.  Enjoy your two weeks away, I'm assuming it's vacation.

Tom S


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## MikeWi (Jul 3, 2014)

terrywerm said:


> The original design called for a straight nozzle that is relatively short in length, and small enough in diameter to keep the air velocity high enough to still carry the droplets, but not so high that the droplets become atomized, thus not creating a fog in the room. The flex hose you are using may be what is causing the problem.


Just adding a plus 1 to this.  The length will be a problem too, but the bends and restriction are certain to turn it back into an atomizer.


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## JimDawson (Jul 3, 2014)

I wonder if this would work.  http://www.homedepot.com/p/Simpson-Strong-Tie-Epoxy-Mixing-Nozzle-5-Pack-EMN22i-RP5/100659424  Might be interesting to try.

http://en.wikipedia.org/wiki/Static_mixer


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## TomS (Jul 4, 2014)

JimDawson said:


> I wonder if this would work.  http://www.homedepot.com/p/Simpson-Strong-Tie-Epoxy-Mixing-Nozzle-5-Pack-EMN22i-RP5/100659424  Might be interesting to try.
> 
> http://en.wikipedia.org/wiki/Static_mixer
> 
> View attachment 79591



My local Home Depot has them in stock.  Might give them a try.

Tom S


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## TomS (Jul 6, 2014)

TomS said:


> Wermie,
> 
> Thanks for your explanation and suggestions.  I've got a kitchen remodel in progress so may not be able to get back to the coolant system for a few days.  But I will post what I did and the end results.  Enjoy your two weeks away, I'm assuming it's vacation.
> 
> Tom S



Broke away from the kitchen remodel yesterday and played with the no fog mister.  I opened up the brass plug in the end of the nozzle from .040" to .125" and re-plumbed the system with one regulator.  With the air pressure set to 20 psi it works much better.  You are correct that the coolant feed needle valve is ultra sensitive.  Maybe the local PetSmart or Petco stores will have an aquarium valve smaller than the 1/8" NPT valve I'm using.  Still need to play around with the inlet air pressure and possibly replace the flexible nozzle with a small diameter rigid tube.  The volume of coolant used is also greatly reduced.  Did about five hours of milling and the level is down about 1" - 1-1/2".

All this being said this is a great system.  Got some heavy milling to do (building a sheetmetal brake for my hydraulic press) so we'll see how it works under those conditions.  Nuf said, heading to the shop.

Tom S.


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## Restorer (Jul 31, 2014)

Wermie,

When I was a young fellow and working in a toolroom, the boss hired an additional man.  He had some gaps in his education and did not understand using proper feeds and speeds on a Bridgeport.
He ordered a "Cool Tool" mister to help reduce his consumption of end mills.  When in use, the small vial on the mister emptyed quickly.  One day Jerry had a "Brainstorm" and removed the vial and plugged on a syphon hose, hung the One Gallon can of "Cool Tool" with heavy wire to the collet rack and went to work!  He had a one inch endmill working on a block of A-2 Tool Steel.   Very soon my Van Norman mill and I were engulfed in a "Blue Cloud" even though it was 10 feet away from the main event!   The tool room was about 20 by 30 feet in size.  I soon walked out of the room.

The plant superintendent came along five minutes later and ask what I was doing?...  I replied waiting for the air to clear! ......

The "Blue Cloud" now had emerged into (3) adjacent areas.  As the Super. looked around the cloud was approx. 10 feet into the area I was standing in.
His face turned BRIGHT RED and he stalked into the "Blue Cloud", dissapearing totally from site.  His yelling could be heard over the racket of a press room.

That was the end of the spray mist!

I have not used one in my home shop, remembering the stench and mess, but will try yours.  Have you tested any of the water mix coolants?

Reguards,
Restorer


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## Terrywerm (Aug 1, 2014)

I used some Kool Mist and some Syn-Kool in my prototype and both worked quite well. A few ounces will last for quite a long time if the unit is set properly. No problems with odor or mist. Air does most of the cooling, with the aid of just a bit of moisture from the coolant itself. 

I still have to build my final design and do a build article on it, but time in the shop has been really tough to come by as of late.


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## wheeler34man (Oct 31, 2014)

I look at this project and I like it. However I have maybe a silly question. When you mix the water and oil is there any concern that the water will completely separate from the oil and cause rust and corrosion on my mill table and/or vice? I dont typically wipe down things immediately after a quitting for the day. But maybe I need to start. I have a heated garage so I don't have worries or rust otherwise. Just a question I have. Thanks! 




terrywerm said:


> I used some Kool Mist and some Syn-Kool in my prototype and both worked quite well. A few ounces will last for quite a long time if the unit is set properly. No problems with odor or mist. Air does most of the cooling, with the aid of just a bit of moisture from the coolant itself.
> 
> I still have to build my final design and do a build article on it, but time in the shop has been really tough to come by as of late.


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## Terrywerm (Oct 31, 2014)

No such thing as a silly question!!  Glad you asked!  The coolant is not very oily, but does have some lubricating qualities. Kool Mist and Syn-Kool both come as a concentrate, and you mix them with water at an amazingly light mixture. I have not had them separate at all, even when unused for several weeks. I have not seen it separate if left in a small puddle either.

I always try to give my machines a quick wipe down when I am done with them, its just a good habit to get into I think. I used to leave things sit and then go on a cleaning binge once in a while. Getting in the habit of cleaning up as soon as I am done helps me to keep my shop area much cleaner. It is nice walking into a clean shop to start on a project, rather than walking in and having to clean up a mess first!


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## middle.road (Nov 1, 2014)

On the first run with my (soon to be converted) ltl Mister, I had the flow set too high. I was using Boelube concentrate which if it's left to
sit seems to attract rust or corrosion.
I was making shackles for the Jeep springs and it was around 2am when I knocked off. I had quite a mess on the mill so being lazy I grab
some fine sawdust I keep in a box and sprinkled it on the mess and hoped the shop gremlins would clean up overnight.
The next morning they hadn't so over coffee I cleaned it up. The surprising thing was that with the sawdust mixed with the chips and coolant,
the shopvac seemed to pick it all up easier. I then wiped it down and tossed on a coat of lube.
Another interesting thing about boelube is that when it does sit it will break down the 'grime' in the t-slots and such. Almost like a caustic degreaser.

_Dan


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## TomS (Nov 1, 2014)

wheeler34man said:


> I look at this project and I like it. However I have maybe a silly question. When you mix the water and oil is there any concern that the water will completely separate from the oil and cause rust and corrosion on my mill table and/or vice? I dont typically wipe down things immediately after a quitting for the day. But maybe I need to start. I have a heated garage so I don't have worries or rust otherwise. Just a question I have. Thanks!



I use Kool Mist in my No Fog Mister mixed per the instructions on the container.  My shop is not heated and I have not yet had a problem with rust.  However, it does get under the vice and discolors the table.  

For info I'm converting a PM-932 to CNC and will use the no Fog Mister on it too.  No flood coolant for me.

Tom S


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## Ski (Jan 1, 2015)

terrywerm said:


> I used some Kool Mist and some Syn-Kool in my prototype and both worked quite well. A few ounces will last for quite a long time if the unit is set properly. No problems with odor or mist. Air does most of the cooling, with the aid of just a bit of moisture from the coolant itself.
> 
> I still have to build my final design and do a build article on it, but time in the shop has been really tough to come by as of late.


 Hi Wermie, How is the final design coming? I have my Lagun about ready to go except for the cooling system. Ski


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## Terrywerm (Jan 3, 2015)

It is done. I managed to work on it a little here and there, and have used it a couple of times now. I just need to get some photos taken and posted. Will try to get that done this afternoon.


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## Terrywerm (Jan 11, 2015)

I discovered that the .040" ID for the nozzle was an error, it works much better at .090".  Alternatively, the nozzle could be eliminated altogether, as the extension tube also has an ID of  .090".  I have updated all of the drawings, all are noted as being placed in the public domain, and they are now available in post #1 of this thread.

I also have photos!  

The first one shows the mixing block assembly mounted on the Clausing mill. The Mini Mag mount works quite well, and the arms and clamp assemblies are of my own making. The clamp assemblies are made from black acetal and the rods are simply 5/16" mild steel rods. The clamp assemblies required the use of fine thread bolts to get enough clamping pressure to keep everything in place.  The valve on the left side of the mixing block controls the air flow, and the one on the bottom controls the volume of coolant. It can be adjusted to use only air, only coolant, or a mixture of the two. The ideal setting using a nice flow of air, with just enough coolant to barely get things damp. It works well anywhere from 10 to 25 PSI.  High pressures and flow rates could potentially cause it to atomize the coolant, creating the dreaded fog in the air, not what we want!







The next photos are shots taken from various angles, showing the whole system off of the mill.  The coolant in the reservoir has been in there since the tool was completed, which was back in September or October. It is a heavy mixture of Rustlick Synkool (thus the blue color) and it has not had any problem with bacterial growth. I brought the entire system in from the garage and placed it in the basement before the freezing weather came this past fall. No problems so far. The nozzle could be omitted since it's ID is the same as that of the extension tube, but it helps to counterbalance the mixing block. These photos also show the small ball valve between the regulator and the reservoir. It is used to stop and start the flow of air and coolant without disturbing the pressure regulator or the needle valve settings.  You can ignore the female quick coupler for compressed air, I needed a pipe plug for that port of the brass cross and didn't have one, also did not have a tee instead of the cross, so the coupler is a stand-in.








So far I am quite satisfied with it, and plan to make another one for WD40. As I mentioned elsewhere, I plan to mount both of them on an old IV stand on wheels, allowing me to easily switch to the proper coolant for ferrous materials or for aluminum, and will allow me to easily move them back and forth between the lathe and the mill. When I make the new one for the WD40, I will take photos as I go and post them here as well. Construction is very straight forward, and is quite easy. The only thing I will recommend is to take your time when drilling the .040" coolant passage in the mixing block. Use a high RPM, and advance the drill slowly, bringing it back out often to clear the chips. If you drill the .090" air passage first, be extremely careful to not break the .040" drill bit when it breaks through into the .090" passage. 

If anyone is interested in drawings for the rod clamps, I have included it here also:  
	

		
			
		

		
	

View attachment Rod Clamp.pdf


Enjoy!!


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## 18w (Jan 11, 2015)

Thank you Terry for the updated information. Looks like you saved me from having to buy the Noga unit.


Regards
Darrell


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## Uglydog (Feb 15, 2015)

Thank you,

Daryl
MN


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## ericg (Mar 5, 2015)

Thanks Terry, 

I have built this no fog mister as per your plans but cannot seem to get it to work as expected, I either get no mist at all or it starts to drip when the needle valve is opened a touch more then it sprays coolant everywhere if opened more.

The only variations to your design is due to Australia using the metric system so I cannot get everything exact, the spray tube is 0.1mm ID instead of 0.09mm ID, the small hole for the coolant is 1mm instead of 1.016mm and the tube inside the reservoir is 8mm instead of 6.25mm, otherwise everything is identical, I have the air pressure set to around 20psi and have varied that up and down to no avail.

I have no idea where to look for solutions, I can post pictures, but it would look pretty much identical to your images.

Any suggestions would be appreciated.

Eric


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## Terrywerm (Mar 6, 2015)

Hi, Eric. Thanks for posting about your problem. I wonder if your expectations were different from what the design is meant to deliver? I see no problems with the dimensions that you used, they are very, very close to the originals and should work just fine.

In operation, turn on the air first, just that it is blowing a little bit, but it should not be hissing loudly. Next turn on the coolant, only slightly, just enough that your finger barely starts to get wet if you hold your finger in front of the nozzle. The amount of coolant coming out will be so little that it is almost invisible, but it is enough to lubricate and cool your cutters.

It is not meant to be a 'mist' system at all, in fact the desire is to not have any mist so that it does not hang in the air in your shop. Instead, it produces very small droplets, but does not atomize the coolant. Some coolants will appear to come through in larger droplets, which is okay too. The old siphon mist systems require quite a bit of air flow in most cases and tend to atomize the coolant, allowing it to create a fog or mist in the air. This design uses air pressure to push the coolant to the mixing block, then uses moving air to carry the fluid out to the work.

Is it possible to atomize the fluid with this system? Yes, if you use high air pressures and high air flow rates. So, keep the pressure at or below 20 PSI, keep the flow rate low also. With the nozzle placed within a couple of inches (40 mm) of the cutter, there should be just enough air moving to blow small chips away from the cutter. Air at that rate will be moving fast enough to carry the small droplets of coolant to the work.

I will see about doing a video of mine this weekend, if there is time. I have a class to teach this evening, and have to go out of town for work already on Sunday, but I might get time on Saturday. If not, I will put it at the top of my list for the following weekend.


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## ericg (Mar 8, 2015)

Thanks for the reply Terry, I used the wrong term when I said 'mist' I simply meant minute coolant drops, which is what I was looking for, I tried many settings with a tissue in front of the nozzle but saw no moisture except when it started to drip, I'll keep experimenting and look forward to your video.

Eric


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## j ferguson (Apr 4, 2015)

Hi Terry,
Thanks for sharing all of this.  I have a Sherline 2000 CNC for which I've just built an enclosure (see thread under Sherline)  with the hope of confining swarf and vagrant coolant.  I'll be cutting complex surfaces out to the machine's horizontal limits but not a lot of Z.  Aluminum.  Your device looks like just the thing in terms of getting some coolant effect without a lot of mess.  It also looks like the straight tube is necessary although since it's easy to make, maybe subject to some experimenting in terms of length and maybe curvature .  Size of the Sherline encourages getting the size of this thing down to minimum.  I also need to mount it on the spindle head and can add a bracket to the motor mount to support the device.

Before I get into this, have you had any other thoughts or experiences with yours which might influence what I do?

John


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## Terrywerm (Apr 4, 2015)

John, you could shorten the extension tube to whatever length works best for you, and you could eliminate the nozzle also. Keep in mind that the extension tube is what gives you some "reach" so that the mixing block does not need to be right near the cutter.

The only thing that I need to change is the clamps for my support bars. The original clamps were made of acetal, but it is too slippery to properly hold the 5/16" rod without slipping. I am planning to make some new clamps from aluminum and see if they work any better. Right now it is difficult to get the nozzle to stay where I put it.

Eric, I have not forgotten about you, either. I still plan to make a short video and post it here, I just have not had any shop time lately.


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## j ferguson (Apr 4, 2015)

Thanks much Terry.  this thing looks like what I need.  I'll post photo when i get it done - few weeks

best regards,
john


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## j ferguson (Apr 9, 2015)

Hi Terry,
I found it interesting that the air passage is drilled to .125 and not the .0.90 diameter of the tube.  I assumed this was to avoid any venturi effect where the .040 coolant passage lets the coolant into the flow.  Pretty subtle.

Cheers.


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## Terrywerm (Apr 10, 2015)

John, sorry I did not reply sooner, I've been out of town since Monday morning, just got home this evening.

I am glad you brought this up about the diameter of the air passage. When the mixing block was first designed, the .125 dimension was somewhat arbitrary, but the block was designed and made before I had any brass tubing on hand. The tubing with it's .090" ID  was based entirely on what was available.

This all leads up to a problem that a few users have talked about with the unit 'sputtering' where the coolant seems to come in spurts. I wonder if a smaller diameter for the air passage would help to reduce that problem??  There is no reason that the air passage could not be .090" instead of .125"     If you have not yet built yours, John, would you mind trying yours with a .090" air passage and let us know how it works?  At some point this summer I plan to make another one and will try the smaller hole, but I have too many irons in the fire to make a new one right now.


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## ericg (Apr 10, 2015)

Hi Terry,
Like yourself I have not had much shop time and had not got the mister working, I was lying in bed recently and a brainwave struck me (very unusual occurrence!), pressure pack spray cans have small pressures and tiny orifices and work well. I thought I would make a nozzle that had an outlet as small as I could drill which was 0.8mm (1/32" or .03"). I tried that which reduced my outlet size by at least 2/3rds and 'bingo' everything is working really well now.
Just thought I would pass my experience on for what it's worth, and thanks again for the project, I will now make a second one to hold WD40 for aluminium.

regards  Eric


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## j ferguson (Apr 10, 2015)

Hah.  I made a very nice block out of 6061 - how I love to fly-cut.  But guess what? first hole and so far only hole was through at .125.  So too late unless I make another one.

Eric are you getting droplets and not mist with your version?

John


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## ericg (Apr 11, 2015)

Definitely fine droplets, no mist that I notice, and the 20psi pressure blows chips away with this smaller opening, however, I still have to properly mount it and use it on a job, just been experimenting so far.
Funny you mentioned fly cutting, that seems to be my latest stumbling block, I cannot seem to get it right, sometimes I do, sometimes not, more practice needed.

Eric


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## Terrywerm (Apr 11, 2015)

Thanks for the input fellas!!  I find it surprising that a smaller nozzle did the trick for you, Eric.  My nozzle was originally .040" and I increased its size to .090" and it worked better at the larger size. Maybe smaller would have been better??  Guess I will have to make a new nozzle when I have the chance and give it a try.


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## j ferguson (Apr 11, 2015)

I haven't completed this thing yet.  My air-compressor showed up today. It's a one horse California ultraquiet - no snickering.  It will only be used for blowing chips and powering the no-fogger.  Mine has to be a stealth shop so noise has to be minimal, and besides i'm only making little things.  I'm also considering pulsing the liquid flow by solenoid valve and timer.  But have to complete no-fogger first, then mess with other modifications.

And thanks Terry for thinking of this thing and Eric for your thoughts.

On flycutting, I'm using Sherline's carbide cutter set to about 2 1/2 inch circle and I don't run it very fast.  I take shallow cuts until piece cleans up then feed out slowly and back even more slowly.  I get a mirror finish.

I worked in a shop when I was a kid 55 years ago.  We built manufacturing machinery.  These projects were assembled out of aluminum plate and cold-rolled.  All the connections were counter-bored socket-head cap screws. Where alignment was critical joints were keyed or pinned.  Every surface including the ones you couldn't see was faced off with a fly-cutter.  These things were beautiful.

All we needed to do was get one machine into a customer's plant and after that we got all the custom jobs.  They loved the conspicuous precision even where it didn't matter.  I loved the work.  As Oskar Trumbull Scalbom, the proprietor used to say, "Just like downtown."'

So my designs may not be intelligent, but they tend to look good.


cheers,

John


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## Terrywerm (Apr 12, 2015)

You will love that California Air Tools compressor. I have one of the 3/4 HP units for the basement shop and it certainly is quiet. It is more than adequate for supplying air for the No Fog Mister and for lightly blowing the chips out of an occasional blind hole. Nobody even hears it run, but my 6 HP unit out in the garage makes its presence known to us and the neighbors every time it fires up.


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## j ferguson (Apr 15, 2015)

Hopefully the rest of the ingredients will show up today.  Following Eric's lead, I'm going to make a nozzle. 'Ought to be a bit of a challenge without a lathe, but I'll forgo the tapered nose.  Terry, you were right about drilling the .040 hole.  It took two tries, fortunately, the bit that broke hadn't penetrated into the .125 passage.  I had planned to use two regulators, one for the air and one for the fluid, but decided that with the needle valves on each line there were too many variables and the thing would be hard to control.

Having a single regulator does provoke a question, though.  The height of the fluid container relative to the mixing block will affect flow if the air pressure to the fluid container and the block is the same.  Has either of you messed with this?


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## Terrywerm (Apr 18, 2015)

I have not experimented with it, but have always kept my reservoir below the height of the nozzle. When I shut off the air, the flow of fluid ceases as well and it does not continue to siphon out through the nozzle as it would if the reservoir were higher.


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## j ferguson (Apr 18, 2015)

Thanks for the note, Terry.  My mixer is finished, photo to follow.  Being latheless, threading the brass tube was a bit of a challenge, but I finally hit on chucking it in the drill press and putting a die in holder on the table.  I was able to turn the chuck by hand to get about 3/8 inch of thread which seemed enough.  Filter holder was ordered from filtersfast which despite their name is none too swift, I'm still waiting.


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## Terrywerm (Apr 18, 2015)

Hmmm.   When I ordered from them I got everything rather quickly. Sorry to hear you are experiencing a delay.

Keep in mind that when I listed Filtersfast.com on the bill of materials I chose them only because they had everything I needed and the prices were reasonable. Other builders can choose another supplier if they wish, but I had good luck with the vendors listed on the BOM.


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## j ferguson (Apr 19, 2015)

Hi Guys,
This is what my effort produced:





The filter holder showed up on Saturday.  Terry you chose well, the thing is really substantial.  I'm going to try it with the.090 throat first and then if that doesn't work, I bought the 1/4 inch hex brass to make a nozzle with. 

And again, thanks to you all for a useful design.

john


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## Silverbullet (May 15, 2015)

When I get my mill mounted to its new table ,I'll have to make this mister too. Love the fact it dosent use gallons of fluid to work. Thanks for the plans .


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## j ferguson (Jun 27, 2015)

At long last, I cleared my backlog of the less fun things, and got started on my SlimVise project.  First act was to make two smaller pieces out of a big one.  This was more of an experiment to see how the no-fogger worked than the best way to do this.  





It worked just fine, and without a nozzle.  i ran 20 psi on the system.  The adjustment of the coolant valve is really twitchy though, possibly because this HomeDepot valve is not intended to meter.  So next "improvement" is to find a real metering valve.  The thing that's nice about this is that you can feel the air stream cool when the coolant starts to feed and also you can see very small droplets accumulate if you aim it at a piece of paper.

I'm glad i made this thing.


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## Terrywerm (Jun 27, 2015)

Mine is touchy about its adjustment also, so it might not be your valve. I am considering making my own needle valve so that I can better regulate the coolant flow, but there are too many other projects going right now. Another method that I have considered is to use two regulators.  One set at about 20 PSI for the air flow through the mixer, and the other set at 30 or 40 PSI to provide pressure for the fluid. I believe that the surface tension of the fluid is high enough that at 20 PSI there is not enough pressure to keep the fluid moving past the needle valve when it is barely even open. More pressure behind the fluid might help, but I don't know for sure.


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## j ferguson (Jun 27, 2015)

Hi Terry,
I bought two regulators with the thought that the fluid and air feeds might work better with different pressures although I was thinking of less pressure on the fluid, maybe depending more on venturi effect to pick it up.  The valves I have are not really needle valves like you used to use for air-correction in carburetors so it's more of an off-and-more-or-less-on choice, not a a gently ramping increase in flow.  You may be right that the stickiness of the coolant could clog a real metering valve.  I guess I'll have to see if i can find one, and then maybe also mess with the air-pressure too.

I have some old propane valves around which have long needles, maybe one of them can be modified to do this job better.


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## JimDawson (Jun 27, 2015)

terrywerm said:


> Mine is touchy about its adjustment also, so it might not be your valve. I am considering making my own needle valve so that I can better regulate the coolant flow, but there are too many other projects going right now. Another method that I have considered is to use two regulators.  One set at about 20 PSI for the air flow through the mixer, and the other set at 30 or 40 PSI to provide pressure for the fluid. I believe that the surface tension of the fluid is high enough that at 20 PSI there is not enough pressure to keep the fluid moving past the needle valve when it is barely even open. More pressure behind the fluid might help, but I don't know for sure.





j ferguson said:


> Hi Terry,
> I bought two regulators with the thought that the fluid and air feeds might work better with different pressures although I was thinking of less pressure on the fluid, maybe depending more on venturi effect to pick it up.  The valves I have are not really needle valves like you used to use for air-correction in carburetors so it's more of an off-and-more-or-less-on choice, not a a gently ramping increase in flow.  You may be right that the stickiness of the coolant could clog a real metering valve.  I guess I'll have to see if i can find one, and then maybe also mess with the air-pressure too.
> 
> I have some old propane valves around which have long needles, maybe one of them can be modified to do this job better.



I run mine at a 15 PSI differential, 45 on the air and 60 on the fluid.  That way I'm assured of having fluid flow at all delivery rates.  I'm using pneumatic flow controls for the fine adjustment, about 16 inches back from the outlet for both fluid and air at the mixing tee.


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## j ferguson (Jul 1, 2015)

After another session with my no-fog coolant device, i have it adjusted exactly right.  It turns out that it just needed more fussing than I had expected, but it now works beautifully, and amazingly doesn't make much of a mess.  the longer handles on the valves make them pretty easy to fine-adjust.


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## Terrywerm (Jul 3, 2015)

Good to hear that you have yours working well. I agree, the valves do require a bit of fussing to get them just right. I keep having trouble with the coolant valve slowly closing itself after I get it set. I attribute that to the rubber o-ring inside the valve. The o-ring always seems to pull the valve back a bit. I have been thinking about making some new seals out of UHMW and see if that resolves the setting problem.


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## j ferguson (Jul 14, 2015)

I was finally able to muster enough smarts to devise a 3 hour CNC run - aluminum.  The difference between none and a bit too much is REALLY twitchy on my coolant valve.  Because I have the little handle and fiber-gland under the cap, I can set it so it's ok, but it is a struggle - I must have just lucked out on earlier short runs.  So I'm going shopping for a finer coolant valve.  I think they call them metering valves.  But no mater what I do, there is NO FOG.


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## j ferguson (Sep 10, 2015)

I finally caved in and bought a proper metering valve, a Parker 1715-003381100.  I think I paid $24 for it on Amazon.

It has a wonderful micrometer adjuster which makes getting the right amount of coolant in the mix EASY.





This is how the whole thing looks:





can never have enough detail:





As you can see, this thing has gotten pretty bulky.  the next move may be to mount the valves on another block of aluminum and just run the tubing into simple fittings on the mister itself.

In any case, the twitchiness on getting just the right amount of coolant in the airstream is gone.


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## Terrywerm (Sep 10, 2015)

Ooooo   sweeeeet!!    Would you mind sharing your source and a ballpark price on that valve?


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## Doubleeboy (Sep 10, 2015)

Terry, they are $24 on Amazon.
michael


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## JPigg55 (Sep 10, 2015)

Just what I've been looking for, thanks Terry.
I know you stated the nozzle isn't necessary, but got me wondering if using Mig welder tips might work and be an easy addition.
Thinking of experimenting with a flexible metal line as well.


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## Terrywerm (Sep 10, 2015)

Thanks Michael!!  I think they would be well worth looking into. I found that the little rubber o-ring in the valves that I used is what is causing the problem there. When you stop turning the screw, the rubber pulls it back slightly, making it difficult to get it set correctly.

JPigg55, it certainly will not hurt to experiment a little. That's how these sorts of projects get better! I've still got the original nozzle on mine and it works just fine. As for the flex nozzle, I think it will give you trouble. Another member tried that some time back and the moving air was unable to carry the droplets inside that 'rough' tube. Straight, laminar flow seems to be an important part of making it work properly. With the flex line the coolant dropped out of the air and built up inside the nozzle until the air could manage to 'grab' it again and spit it out in spurts. Not trying to discourage you, but just letting you know what we saw happen before.


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## JPigg55 (Sep 10, 2015)

terrywerm said:


> As for the flex nozzle, I think it will give you trouble. Another member tried that some time back and the moving air was unable to carry the droplets inside that 'rough' tube. Straight, laminar flow seems to be an important part of making it work properly.


Yeah, I read that and saw the picture. Was thinking more of a flexible line like the old oil cans used, metal, spiral wound type. Might work, might not, never know until you try I guess.


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## Terrywerm (Sep 10, 2015)

Ah, yes. It may certainly be worth a try!  Another material I thought of that may work would be the type of plastic that are used for the suction tubes at the dentist office. They are hard plastic, smooth on the inside, but can be bent and they retain their shape.


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## j ferguson (Sep 11, 2015)

http://www.amazon.com/Parker-003381...441945657&sr=8-2&keywords=parker+needle+valve


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## JPigg55 (Oct 26, 2015)

For convenience, I combined all the PDF files into one file.


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## j ferguson (Dec 8, 2015)

FWIW, I now have a lot of experience with the Parker metering valve.  using 20 psi into both the fluid and air ports, I find that the setting for the metering valve which produces the best flow (very slightly wet) is still tricky - very close to fully closed, BUT, and it's a big BUT, it can be found and once set seems to hold through a run, which for my jobs can be an hour or two.  It's pretty hard to see the actual output of the tube at this setting, but what I've been doing is adjusting until I see some fluid coming out the tube, then reducing the flow until i still see fluid accumulating on workpiece but cannot see stream itself.  I've mostly been cutting aluminum and get good finishes and no  chip-sticking.  chips do clump up though and I have to blow them away from time to time.

It's amazing how little fluid gets used in two hours yet there's enough to see on the workpiece.
Useful.


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