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firetrappe
31-10-2014, 12:22 PM
I've been looking at buying or building one of these systems for the past few weeks. Lubricating a cutter and clearing chips manually with my airbrush is getting old quickly!

Ideally i'd like a system where I can use just air to clear chips (useful for materials such as acrylic) or mix coolant into the airflow for aluminium jobs.

I've read all the threads I can find on 'Fogbuster' type systems. The plumbing seems simple enough, but the 'mixing blocks' look like there is quite a bit of work involved.

Since I'd have to source and buy suitable needle valves, taps, fittings etc, I'm wondering whether it's worth taking a punt on one of the ready-made units from China : http://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20141031022954&SearchText=coolant+mist

Has anyone imported something similar rather then making their own or shelling out 500+ for a system from a UK supplier?

JAZZCNC
31-10-2014, 02:18 PM
Since I'd have to source and buy suitable needle valves, taps, fittings etc, I'm wondering whether it's worth taking a punt on one of the ready-made units from China

Problem is Si they are mister so work on venturi affect which creates the fine mist and chokes you to death.!! You wouldn't live 5mins in your little place.!!
You need a pressured system that injects drops into the air flow. Actually very easy to make but requires pressure vessel and valves etc.

Or just have 2 pipes one for air and another with collant drip feeding into the air flow.!!! . . . . Simplizzzzzzzz

Boyan Silyavski
31-10-2014, 11:32 PM
May be you are already aware of these plans (http://www.machinistblog.com/zero-fog-mister/), seems quite cheap and easy to build.

I am also contemplating how to do it.

Perhaps the cheapest and least complicated way to do it will be to dedicate small air compressor +the nozzle from the plans above.

Now comes to my mind that instead of fiddling with pressure tanks, connectors and so, it would be best to use the compressor tank itself and half fill it with cooling liquid. So the drain valve connection will feed the cooler line, the air will come from the air line. Both lines will go into the nozzle and mixture will be regulated via needle valve there.


So basically the only modification needed will be fit inlet valve from where the liquid goes in. Though can be done by simply unscrewing the regulator above or the liquid line below and refill, without any modification.

firetrappe
01-11-2014, 11:52 PM
Dean - Thanks for the input. I realised the ones I linked to are used the venturi principal which atomises the droplets. This is the effect i'm getting at the moment using my cheap airbrush setup (http://www.rdgtools.co.uk/acatalog/COMPLETE-AIRBRUSH-KIT--2-AIRBRUSHES---COMPRESSOR----HOSE--45643.html)
And you're right, the fine mist created is horrible and fills my little shed in minutes! I was thinking of using the mixing block etc from one of those systems but feeding it from a pressurised coolant container.

Silyavski - Thanks for the link to those plans. I'd seen them before, but they were linked to from this thread (http://www.cnczone.com/forums/general-metalworking-machines/102934-built-fog-less-coolant-mister.html). Karl_T recently modified that system as it didn't work well with air-blast only (see post #64) (http://www.cnczone.com/forums/general-metalworking-machines/102934-built-fog-less-coolant-mister-6.html#post1484142).

I like your idea of using the compressor's tank as the coolant dispenser. My only concern would be that you would get water mixed in with the coolant (not a big issue) but you're also likely to get rust particles contaminating/blocking the coolant line.

My preference would be to have 2 regulators coming from the main tank outlet, one for air pressure, one for coolant pressure. Feed the coolant line into one of these (http://www.amazon.co.uk/Water-Filter-Housing-Brass-Standard/dp/B00JVZ0XMK/ref=sr_1_cc_1?s=aps&ie=UTF8&qid=1408471447&sr=1-1-catcorr&keywords=10+clear+bowl++filter+housing) (as shown in the link above) then to the mixing block and run the air line directly to the mixing block.

I'm also thinking that it might be beneficial to have 2 lines/nozzles from the mixing block rather than one. I think that 2 nozzles at 90 to each other would be more effective at clearing chips from deeper slots when using air blast only. Maybe one for air and one for mist, with the option to use both as air only.

I'll keep reading and searching suppliers to see if I can come up with plan.

Boyan Silyavski
24-03-2015, 11:55 PM
Some update. i like designing and challenge.
I tried the way they tell it but the effect was not to my liking. The spray pattern was not good and the control of the flow was lame.

So in my free time i started experimenting and little by little i designed my own fog-less mister cooling. Bellow is a video of me testing the nozzles while Jeff is cutting my Z axis spindle mount, this today. Unfortunately the phone battery run low so i captured the moment with too much flow from the nozzle, you can see the mist at the back, though in fact its no mist but droplets, there was too much flow. So the video is of how it should not be, but you can see the cleaning effect of the air blowing away the chips.

Later when i lowered the flow it was perfect, blowing the chips, cooling the bit but at the same time no mist in the room after half an hour milling. I am thinking to manufacture some and sell them for a reasonable price.

What i can say is that just sticking tubes together as per some drawing does not work well, all flow connections and transitions should be well thought and shaped, plus the exit nozzle must be shaped properly. when done properly the flow seems to reach ultrasonic speed judging by the sound and at the same time does not mist but forms nice, thin, long, properly shaped flame like cloud that disappears completely after hitting the material. The best result is when at the middle of the "flame" at "ultrasonic" speed forms a nice needle like thicker stream of droplets.

what i mean without wanting to insult somebody is that after i played around and experimented for a couple of days, i saw that even a product which all worship and is worth 350$ is not so well thought of, as they want us to believe. Some day when i have more time will illustrate what i say with photos and proper video. lets say that with the bigger flow nozzle when adjusted properly i achieved a 40-50cm long stream where at this long distances is only 5cm wide and still no mist there. Its only flow being too much flow, though maybe for stone will be ok. In fact if there was a reflector at the back where the flow could hiot it there was no mist at all, cause all droplets were falling down. The problem comes with too much flow and nothing to stop them. At the end there is transition to mist, so that must be avoided, by limiting the flow for example or the nozzle size and shape.


For now a crappy video of the system . Forgot to say also- crappy Chinese valves and speed adjuster did not work. Same with custom valves made from this and that. But "made in Italy " valve worked like a charm for precise flow control. Guess why.


https://www.youtube.com/watch?v=6wFqyHL5fcY&feature=youtu.be

johnsattuk
25-03-2015, 01:31 AM
I got fed up with trying to get the flows right, so made this

Boyan Silyavski
25-03-2015, 07:58 AM
I got fed up with trying to get the flows right, so made this


You could sell that at Etsy as steam punk art :hysterical:. Man, its beautiful. Looks like a mist cooler coming from the future or like something savaged from a spaceship station

johnsattuk
25-03-2015, 10:02 AM
Totally independent control of Fluid and air, air can be pulsed for better pocket clearance,without affecting the amount of fluid delivered. Can squirt fluid alone (up to 90 cc's a min )for some jobs.

Fluid container can be put wherever you like ( within reason) , does not siphon or drain back, will handle different viscosity's .

JAZZCNC
25-03-2015, 10:19 AM
Totally independent control of Fluid and air, air can be pulsed for better pocket clearance,without affecting the amount of fluid delivered. Can squirt fluid alone (up to 90 cc's a min )for some jobs.

Fluid container can be put wherever you like ( within reason) , does not siphon or drain back, will handle different viscosity's .

I Like the sound of that John and very well made. . . . Got couple of Q's if you don't mind answering. You may have just added another Job to my endless list.!

Whats on the heat sink on right.? Looks like thermister, resistors and black box which I'm not sure about.! And what are they doing.?
What and where's the power source.? ie voltage.
Where did you get the peristaltic pump.?

Boyan Silyavski
25-03-2015, 10:20 AM
That being said it still leaves the question of the nozzle/delivering tube/body /support/connectors assembly. How do you do that?

Another question is the complexity, some times simple things last longer in industrial enviroment , on the other hand it can be expensive for eventual time to time home use or on a small cheap machine.

I mean is one thing to design an usefull system. My Russian friend who is an experienced model maker did his system for under 5 minutes from what he had at hand.
Its another thing to design cheap, clever, reliable and nice looking product/in that order that could cover most of the real needs of fellow machinists.

You made that for yourself or with the idea of selling it?

And when you will need the squirting? from my experiments even tiny tube could give tremendous flow. In fact for comparison 1mm nozzle gives 160l/min flow if i remember correctly some plasma cutter torch specifications

johnsattuk
25-03-2015, 10:43 AM
Whats on the heat sink on right.? Looks like thermister, resistors and black box which I'm not sure about.! And what are they doing.?
What and where's the power source.? ie voltage.
Where did you get the peristaltic pump.?

Not really a heat sink, just a packer. underneath is an SSR to control the air valve, the square with a red blob is a 12v lamp-flasher which gives me the pulses, next to it is a 12v reg. (with a couple of ceramic capacitors ) needed because I am supplying 24 volts from my main panel. The AUTO mode is an M7 relay in the panel.

www.wmcpumps.com as on the back of the pump. I chose a 3mm tube but if I replace it will use a 1.5 mill

JAZZCNC
25-03-2015, 10:50 AM
My Russian friend who is an experienced model maker did his system for under 5 minutes from what he had at hand.


I could make a crude system in 1min by just piercing tiny hole in bottle and letting gravity do the work dripping droplets in front of my air nozzle. It would have the same characteristics has Johns system in that it would be independant control of air and fluid but I wouldn't because it won't be affective and look shite.!! . . . . I don't get your point is what I'm trying to say.!

John's system is metered indepedant control of air and fluid which in practice will be be much more usable than any Fogger sytem. I would relate Fogger equivalent to normal hammer and based on my experience estimate Jonh's sytem to be equivalent to Piano tuners hammer.!! . . . . Both hammers but different.

johnsattuk
25-03-2015, 10:55 AM
That being said it still leaves the question of the nozzle/delivering tube/body /support/connectors assembly. How do you do that?

Another question is the complexity, some times simple things last longer in industrial enviroment , on the other hand it can be expensive for eventual time to time home use or on a small cheap machine.

I mean is one thing to design an usefull system. My Russian friend who is an experienced model maker did his system for under 5 minutes from what he had at hand.
Its another thing to design cheap, clever, reliable and nice looking product/in that order that could cover most of the real needs of fellow machinists.

You made that for yourself or with the idea of selling it?

And when you will need the squirting? from my experiments even tiny tube could give tremendous flow. In fact for comparison 1mm nozzle gives 160l/min flow if i remember correctly some plasma cutter torch specifications


Since there is no requirement for a venturi or pressurized container almost anything works, I just used an old NOGA that I had.

I made it for myself, I have no commercial intentions whatsoever. I am 80yrs old and in the middle of a delayed midlife crisis.

If you don't need squirting, then don't use it

JAZZCNC
25-03-2015, 10:59 AM
If you don't need squirting, then don't use it

Quote of the Day.!!. . . . So so funny I just took a bite of toast and gulp of tea as I read that and now my Laptop looks like a damp loaf. . :hysterical:

JAZZCNC
25-03-2015, 11:05 AM
Not really a heat sink, just a packer. underneath is an SSR to control the air valve, the square with a red blob is a 12v lamp-flasher which gives me the pulses, next to it is a 12v reg. (with a couple of ceramic capacitors ) needed because I am supplying 24 volts from my main panel. The AUTO mode is an M7 relay in the panel.

www.wmcpumps.com as on the back of the pump. I chose a 3mm tube but if I replace it will use a 1.5 mill

Thanks John I got the Jist of what would be needed to make this work from pic and the Reg I recognised but it was the Blackbox with what looked like a Thermister above it that thru me off.! . . . . . Now I look again can see it's part of the black box.!

Boyan Silyavski
25-03-2015, 11:08 AM
That with the pulsing seems a great idea. I missed that.

johnsattuk
25-03-2015, 11:31 AM
Thanks John I got the Jist of what would be needed to make this work from pic and the Reg I recognised but it was the Blackbox with what looked like a Thermistor above it that thru me off.! . . . . . Now I look again can see it's part of the black box.!

I didn't mention the round black item - this is just a small air reservoir mounted directly on the air valve, (bigger would be better but its what I had lying about) it gives a bit more bite to the pulses and dampens the air gauge a little.

Boyan Silyavski
28-03-2015, 03:42 PM
Just a note about my vision of the correct flow shape. I would like to illustrate how i like it. See photo below.

I maxed the cooling supply so its more clear whats happening. When milling aluminum you can barely see the coolant flow. When nozzle properly made /IMO/ the overall "flame" shape is long and concentrated and in the middle forms a very nice thicker stream, it basically sounds like a nice small propane turbo burner . No mist at all. You hit a wall with this stream and it all goes down, nothing up in the air.

that stream bellow is should be enough even for engraving stone and soon i will try it when i have my machine ready :-)

http://www.mycncuk.com/attachment.php?attachmentid=15021&stc=1