Mist Lubrication - Fogbuster

[cfellows]

I made one of these for my milling machine.  It provides a jet of air with a really fine mist of WD40 to clear chips and lubricate the work when milling.  Works well and doesn't make a mess. 



This is kind of a stylized drawing.  The actual device uses threaded inserts with 0-rings but I don't really know how important those are.

Chuck

[10KPete]

I guess the subject title answers the question but I'm gonna ask anyway: Do you get any 'fog' floating around with that
set-up? I used to use CoolMist at work years ago and hated the fog they produced. Those devices mixed air and fluid at
the nozzle.

Pete

[tangler]

Yikes Chuck    Are you sure you haven't just invented the flame thrower?

It's great to see you back in the workshop and we can't afford to lose you just yet!

Rod

[MMan]

Yes, someone mentioned WD40 to me a while back - I was spraying WD40 and vacuuming up the swarf. The can says the stuff is highly flammable, my little vac never lit up but I have stopped now and changed to suds in a squeezey bottle.

This mister should work with suds too and I have been wanting to build one for a while so, Thank You Chuck, and another item in my TODO list.

Mman

[MMan]

Hi 10KPete,

Yes, the alternative is the FogBuster which pressurises the coolant reservoir so that less air is needed at the mixing head and hence less fog. The real thing is expensive but not much different to what Chuck has here.

Mman.

[10KPete]

AaaHaaa! Pressurized liquid supply... That would do it all right. I've been trying to figure out how to do something like
this and I think Chuck has come up with the answer.

Thanks Chuck!!

Pete

[RonGinger]

I used to use CoolMist at work years ago and hated the fog they produced. Those devices mixed air and fluid at
the nozzle.

If it made a fog you were using way to much fluid and air. A friend has a Bijur coolant spray and you have to hold your hand in front of it for several seconds to accumulate even a drop of liquid. I think most of the cooling comes from the air, with a tiny amount of fluid as lubricant.

I bought a cheap one and could never get the mix right. I also hate to have the air compressor running. Now I just use a spray bottle of WD40 and give a small squirt every few seconds.

[cfellows]

Thanks, guys, for all the comments. 

This doesn't produce a fog unless you have the air flow way too high.  You can't see a mist at all and have to hold a little scrap of paper in front of the nozzle to adjust it to where the paper starts "wetting". 

Tangler:  I don't think the mixture of WD40 and air is rich enough to burn. 

Ron:  I have a 20 gallon tank on my compressor and this thing runs on 5 - 10 PSI, so it doesn't cycle on very often.

Here's a couple of pictures of...





The container in my setup is a plastic soda bottle which seems plenty robust for small amount of pressure is set at.  I did buy a small, water filter container that I'll probably replace the bottle with eventually.

To use the system, the air pressure is first adjusted on my compressor.  Then a single line goes to the vessel which holds the WD40.  The line is split with a tee, one line going into the top of the container, the other line going directly to the air connection on the fogbuster.  A second line goes from a siphon tube in the container to the WD40 connection on the fogbuster.  As MMAN says, the container is pressurized which forces WD40 to the fogbuster.

When I first made the device, I omitted the air adjustment screw, depending only on the pressure regulator on my compressor.  However it, it was hard to keep in adjustment and required a lot of pressure to feed the oil.  Adding the air adjustment screw let's me use less air but still enough to keep the chips clear.

I used to just use a spray can of WD40, as Ron does, but you need a continuous spray of air to keep the chips clear as recutting chips really shortens tool life.

It turns out that buying WD40 by the gallon is pretty inexpensive compared to the aerosol cans.  And, the amount of WD40 this thing uses is pretty small.  A quarter cup or so in my container will last several hours of run time.  There's no accumulation, re-circulation or filtering of fluid needed.  At the end of a run, a rag easily mops up the small amount of residue.

Chuck

[Bearcar1]

That's brilliant Chuck. Simplicity at its finest and yet quite practical. I like it! AND, I just so happened to toss a small drop piece of aluminum in the drawer a couple of nights ago. You have provided the answer to the question that has kept me awake at night thinking "what am I ever going to use that for", now I know.   What size of tubing did you use?


BC1
Jim

[cfellows]

Thanks, Jim.  The Urethane tubing I used is .25" OD, although I think 3/16" or even smaller would work fine.  Probably wouldn't use anything larger.

The brass fittings I made from 1/4" hex rod and used 1/4" x 40 model pipe taper threads into the aluminum.  The outer threads on the air and oil adjustment screw fittings are 1/4 x 28 fine theads and a 1/4" x 1/8" O-ring is placed under the cap to prevent leakage.  Haven't added an o-ring and cap to the air adjustment screw yet.  Don't know if it's even necessary...

Chuck

[10KPete]

Ron,

That was back in the mid '70s and I guess it was a new deal then. The only adjustment I recall was one valve, I believe at
the fluid tank. ??? I remember it was a siphon sort of thing; took a few seconds after turning it on for the fluid to get to
the nozzle. And it was a water based fluid.

Pete

[BillTodd]

I like that Chuck .... another project ... all I need

[cfellows]

Thanks, Bill.

I've been watching videos on youtube by NYCCNC and the most important part of milling is clearing the chips out so your always cutting into the work, not re-cutting chips, sometimes over and over again.  Apparently re-cutting chips shorts end mill life by dulling them (much) faster and by causing small pieces of the cutting edge to get broken off.  The WD40 is probably less important, but does provide some cooling, reduces friction, and improves surface finish, particularly on aluminum.

Chuck

[Dave Otto]

Re cutting chips also sounds awful and creates a lousy surface finish on your parts. I think a lot of guys don't realize this; or just don't care. I have a dual nozzle Micro-Drop system on my mill at home controlled with a solenoid valve and relay, this way my G-code can turn it on and off. This does a pretty good job of keeping the chips clear; flood coolant would be nice but I'm not prepared to deal with the mess.

Dave

[Tennessee Whiskey]

Nice one Chuck. I bought a Kool Mist to use on thin parts on the surface grinder and today I moved it over to the mill for the first time and noticed a big difference in the sound of the cutter and surface finish. Having the chips blown out was really nice for seeing what was going on also.  I'm using the Kool 77 fluid, I think it is.  I also mixed up a spray bottle of water soluble oil I bought for the Grizzly grinder that was junk.  It did a better job than I expected on some turning today, wonder how it would work in the mist? I also wonder if some cheap drugstore rubbing alcohol mixed with water would provide any extra cooling in the mist  .

Cletus