MQL or mist coolant

[lucsimoneau]

Hi all, hope you are all doing well.
I'm presently using the following mist coolant setup obtained from AliExpress for a few bucks:



The problem I'm having is that my compressor (Maximum 15-Gallon Oil-Free Portable Vertical Compressor) runs almost continuously to keep the aire flow and mist going.

I've been reading about a Fog Buster system and it seems to require les air from the compressor. The company states that a 5 gallon compressor is sufficient.

Do any of you have some experience with the Fog Buster system and the feasability to do a DIY solution?

Thanks!

 

[DPittman]

I've got a similar setup and also find my little (but no oil free) compressor runs practically non stop. The Fog Buster company statement of it only requiring a 5 gallon air compressor is meaningless, as you know as you have a 15 gallon compressor. The CFM output of a compressor is what matters. I look forward also to hearing from those that have the Fog Buster system.
What coolant/ fluid are you running in your system?

 

[lucsimoneau]

Presently using Kool Mist 77:

 

[Former Member]

The issue with misting systems is they require air, and sufficient volumes to create a vacuum to pull the cooling fluid into the stream and atomize it. I have the Cool Mist system and it helps when flood cooling is not and option and brush applied lube/coolant can be inconvenient.

Personally, I find flood cooling is great (messy) but great all the same, brush applied solution is next and finally mist.

 

[Tom O]

I don’t have one of those but I have to ask what min/max pressure have you tried running at and where is the coolant reservoir the lower it is the more air flow to raise the coolant.

 

[DavidR8]

The issue with misting systems is they require air, and sufficient volumes to create a vacuum to pull the cooling fluid into the stream and atomize it. I have the Cool Mist system and it helps when flood cooling is not and option and brush applied lube/coolant can be inconvenient.

Personally, I find flood cooling is great (messy) but great all the same, brush applied solution is next and finally mist.

I'm thinking about flood for my incoming mill. Would appreciate seeing your setup.
Feel free to drop a pic or two in my Shop Shenanigans thread.

 

[jcdammeyer]

Recall when you were over that I have this assembly. It's designed to feed both air and liquid separately to the nozzle which then atomizes it at the tip. I can restrict the amount of air and fluid. The up side of this approach is the fluid container is under pressure so it's ejected out even if the cooling air is restricted. The idea was to avoid too small a particle atomization with stuff in the air that gets breathed in.
We only used it for cooling air when we pulled the TTS holder out of the R8 collet.

 

[DavidR8]

Recall when you were over that I have this assembly. It's designed to feed both air and liquid separately to the nozzle which then atomizes it at the tip. I can restrict the amount of air and fluid. The up side of this approach is the fluid container is under pressure so it's ejected out even if the cooling air is restricted. The idea was to avoid too small a particle atomization with stuff in the air that gets breathed in.
We only used it for cooling air when we pulled the TTS holder out of the R8 collet.
View attachment 34331

That's essentially a Kool mist type of approach right?

 

[jcdammeyer]

That's essentially a Kool mist type of approach right?

I don't think so. Their tanks don't look like they are pressurized.

Kool Mist - Spray Mist Coolant Systems, metal cooling system, Mill Coolant, Tool Coolant, Lathe Coolant, Machining Coolant, Flood Cooling

Call 562 246 0949 - Kool Mist manufactures portable spray mist cooling systems ideal for Mill Coolant, Flood Cooling tool Coolant, Lathe Coolant, Machining Coolant, and mill coolant for parts made from metal, wood, plastic and fiberglass. The Kool Mist system removes heat, allows improved...

koolmist.com

OTOH, I also bought a small pump to push the fluid in case the pressurized system didn't work to my satisfaction. Can't believe I ordered it back on the 21st of August 2021. Took a while to go through Aliexpress to find it.

https://www.aliexpress.com/item/4000602374795.html

Haven't used it yet.

 

[jcdammeyer]

Oh and one friend built a similar one and just used a 2L coke bottle as the vessel to hold the coolant.

 

[Former Member]

I'm thinking about flood for my incoming mill. Would appreciate seeing your setup.
Feel free to drop a pic or two in my Shop Shenanigans thread.

Be a couple of days before I get photos.

 

[kstrauss]

You might find the original fog buster patent of interest if you want to make your own.

 

[jcdammeyer]

You might find the original fog buster patent of interest if you want to make your own.

Yes. I referred to that when I built mine.

 

[Mcgyver]

100% agree with John. When I built mine I did a lot of research and asking and pressurized tank and separate controls for coolant and air pressure was what the guys in know said. I think they were right, it works like a charm with no fogging which is the common complaint of cheapos and most diy ones. The idea is you tune it so you are getting microdroplets that are travelling about the same surfaces speed as the wheel so they land on it. I made my own regulators to make things compact and used an old propane plumbers bottle for the pressurized coolant tank. I use it on a tool grinder and you can almost creep grind without heat buildup...easy to take 1/8" off (which makes preparing new tool bits faster)

This project is grinding an internal buttress thread cutter for Schaublin collet draw bar

 

[Former Member]

A little update, changed the spray nozzles, slightly shorter profile better flow, no integrated shutoffs. Better pump with about 25% more flow. Added a manifold to allow fluid to nozzles or the added wash down hose, this is a god send as wet as it creates a lot less mess than air blast and almost as good. Photos coming, will be traveling for business so it will be a week or two.

 

[Former Member]

Finally a chance to take photos

The revised mount and valving.


The nozzles are no longer valved and all three spray. Its good and bad, but it takes less space and is less bulky compared to the previous method while being less prone to mis-adjustment loading material.

The valve below works as follows:

Upper hose left is coolant in,
Lower hose/valve is coolant return (by pass to tank, usually closed, allows control for future higher pressure/volume pump if needed),
Bottom hose left goes to the spray head (valved to control flow and shut off if needed during wash down),
Bottom hose right is a wash down hose (again valved to prevent leakage and pressure loose in system). This was one of those ideas that would either be good or bad.

Once you use a wash down hose instead of air you won't go back to air, there is considerably less mess to clean up. Not saying you don't still need air to clean up and clear scarf, but considerably less air.

Hopefully this satisfies the curious.

 

[Former Member]

Update, I've been pushing the machine hard and topping up the fluid. Currently the shielding retains 99.9% of the fluid (which is good no wet mess), but this now indicates how much fluid is evaporated to keep cutters cool.

Its a lot. This shows how much cooling is required to keep cutters cool. Considering the in the scope of machines out there mines a true light weight makes it even more impressive.

I'm now going to have to measure the amount for a given run time to determine amount used per hour of runtime.

 

[Tom O]

I know the Haas tip of the day says to operate the auger intermittently so the chips have time to drain to the sump.

 

[Former Member]

I know the Haas tip of the day says to operate the auger intermittently so the chips have time to drain to the sump.

Wish I had an auger, I need to clear manually.