coolant dilemma

[blighty]

hi all.

been having a bit of a dilemma when it comes to the coolant on the old cnc mill.

as i have been doing a few mods to the mill over the last few months, its chip rate has increased some what to the point that the coolant system i have a the mo cant clear the chips away. it's ok (ish) and will clear chips on lets say external cutting, but anything to do with a pockets then forget it. so i have been having a look at what the big boys are using.

high pressure flood coolant...

this is just a really big pump that will squirt coolant at the work at a phenomenal rate. i have seen a few on YT that are using pumps that can deliver up to 10'000lt/hr(2'300gl/hr) this will just blast the chips out.

mist coolant......

mist coolant uses a form of air brush type thing that will spray a fine mist of coolant using an airline and blows the chips away.


pros/cons.....

flood coolant is very messy.
trying to get 10000 lt/hr back into the coolant tank is an art in it's self.
will need to do a full enclosure.

will have to get a very noisy compressor that can do 14cfm and it will be running 95% of the time.


what do you guys think?

 

[Dalee]

Hi,

Chip control is flat out messy no matter how you do it. So you are probably going to be stuck for some kind of enclosure.

Those high pressure external coolants systems ain't all that either. There is still dead spots. Through the tool coolant is best in my opinion. But that is most likely beyond the home shop.

There are some designs of misters that should work for you. Look at pressurized reservoirs to limit air useage. These are pretty low pressure, needing only 5psi or less for the reservoir and the air flow is adjusted separately. You can limit the air volume needed quite easily.

I haven't been forced into a coolant system yet, but I will be soon. And this is the route I intend to go.

Dale

 

[10K Pete]

Chuck Fellows posted on a "Fog Buster" type system he is using and it is of
the low pressure reservoir/low volume air type. That's the one I'm going to
build for my shop.

Pete

 

[chrsbrbnk]

I just have some doubts about the idea of mist coolant both from breathing in the coolant can't be healthy and the coolant mist gradually gooing up everything

 

[10K Pete]

Well, that's the thing about the Fog Buster concept. It doesn't make a mist,
doesn't use water (unless you want it to), doesn't use a lot of air and doesn't
make a mess.

I'll try to dig up the thread but it was not too long ago so you should try to
find it.

Pete

 

[Dalee]

I just have some doubts about the idea of mist coolant both from breathing in the coolant can't be healthy and the coolant mist gradually gooing up everything

Hi,

The idea of the fog buster is to use so little coolant that it takes a fair number of seconds to even feel dampness on your fingers or paper. The coolant provides lubricity and the air does the vast bulk of the cooling and chip evacuation. This also makes them quite economical to use. It's the recutting of chips that really kills a tool in use.

I like the Fellows design and will base mine on his work.

Dale

 

[blighty]

I just have some doubts about the idea of mist coolant both from breathing in the coolant can't be healthy and the coolant mist gradually gooing up everything

thought someone would bring that up... good point too. as chrsbrbnk says, misters can be very bad for ones health. as the tend to put a fine mist of coolant in the air... you could call it a "fog". hence the name Fog buster. fog busters do what they say on the tin. instead of a mist like an airbrush would create. a fog buster sort of drips large drops of coolant into the air stream. so you get a sort of splat of coolant.

i got some some misters of ebay just to have a play. they work well at 10psi. but my little compressor cant keep up with them. and they do fog the place up, after a few minutes you can actually taste coolant.

Chuck Fellows posted on a "Fog Buster" type system he is using and it is of
the low pressure reservoir/low volume air type. That's the one I'm going to
build for my shop.

think i may of seen this one. there are a few vids on YT with guys making fog busters and getting good results.

why are you going for this. over flood coolant? would like to here your reasons.

Hi,

Chip control is flat out messy no matter how you do it. So you are probably going to be stuck for some kind of enclosure.

Those high pressure external coolants systems ain't all that either. There is still dead spots. Through the tool coolant is best in my opinion. But that is most likely beyond the home shop.

There are some designs of misters that should work for you. Look at pressurized reservoirs to limit air useage. These are pretty low pressure, needing only 5psi or less for the reservoir and the air flow is adjusted separately. You can limit the air volume needed quite easily.

I haven't been forced into a coolant system yet, but I will be soon. And this is the route I intend to go.

Dale

ok.... 2 for the fog buster. must admit, i have seen more fog buster types then high pressure coolant. seems that getting 10000lt/hr back into the tank is the problem. one guy had a 3" return pipe and it was still struggling.

through tool cooling.... that would be awesome!! but i cant figure out how they even do it let alow build it........ yes, i know they squirt it down the spindle, but how do they do that with a draw bar in the way.


looks like ill be going for some sort of fog buster type thing. so the question is now..... how the hell do you shut up a 97db compressor?
the compressor i have a the mo is one of them silent ones @40dB but only 1.75cfm 50% duty cycle. to run fog busters you need at lest 10cfm for ever and a day.

 

[10K Pete]

10 cfm seem about x10 too high! Chucks unit produces only a whisper of
air, just enough to move the chips away. And they are dry chips too, not
all wet and stuck together.

Gotta find that thread!!!

Pete

 

[10K Pete]

OK, I found it:

http://www.modelenginemaker.com/index.php/topic,5474.msg104974.html#msg104974

Pete

 

[toolznthings]

I've been using the " real " Fog Buster units for at least twenty years. I have four units used on mills and lathes. This type of unit produces no mist in the air and works very well. Very flexible in adjustment with control over air and fluid volumes. So whether you make or buy a unit I think you will be pleased with the overall results. Is it a substitute for flood coolant in all applications , no. But, overall it gets the job done without the mess and headaches of flood coolant.

Brian

 

[blighty]

OK, I found it:

http://www.modelenginemaker.com/index.php/topic,5474.msg104974.html#msg104974

Pete

thx for finding the link..... looks like a good build. but as one of the post said, no mention of the cfm rate.

i think this psi / cfm is kind a like heat and temperature, two completely different things.

it seems all these busters run on 5 to 10psi. thats fine, but whats the volume of air needed. the misters i got wil run on 10psi blow all the chips out, but with a full air tank (25lt) the pump will come on after a 30 odd seconds and empty the tank in about 3 minutes. from that point the compressor cant keep up. even Chuck doesn't say in his post what cfm his compressor is.

toolznthings........

what cfm is your compressor rated at.

 

[blighty]

been hunting around the net see i can find anything about what compressor to use.
fogbusters website says nothing about it, well not that i could find. Tormach does do a fogbuster kit with compressor for there machines.

found this vid
[ame]https://www.youtube.com/watch?v=bLa0CsjAgro[/ame]

not to sure about the compressor.

from a full tank of air, he runs it at 7psi for about 40 seconds. he then turns it up to 15psi and leaves it there. at the 64 second mark the compressor turns on. about 20 seconds later there is a edit jump. he then does tests with a bit of rag for 50 second then turn the fogbuster off (compressor still going) turns the buster back on 30 seconds latter, edit jump and then the compressor turns off........ and yes, i have nothing better to do.

going by this vid. i don't think that compressor will ever keep up with the fogbuster.

while looking at this, what coolant do you use in these things's? Chuck used WD40. others i found had paraffin. but most run the stuff bought from the fogbuster people. can you just use "normal"coolant?

 

[toolznthings]

I use a large compressor for all my other needs so can't relate to just the fog buster. I seldom operate the unit at more than 10 psi and usually lower. Can't help on the cfm, never really gave it a thought. I'll see if I can fine some info for you.

Brian

 

[Dalee]

Hi,

At 15psi in the video he's really moving a lot of air. Kind of a worst case scenario for heavier chips and deep pockets. And yes, even that compressor will "keep up". It will run more than larger compressor, but it will handle the job.

The reason his compressor kicks on seemingly fast is lack of reservoir volume. Even a 25hp screw compressor would run nearly continuously. A larger reservoir would lessen time between run cycles.

But a larger or more tanks need to be balanced against how much the pump can put out. Too small of a pump to volume of tanks/line system = longer run cycle. Too big of a pump and not enough reservoir = too many cycles. It's a balance.

Noise issues, my solution is to keep my compressor outside of my shop room. This lessens the noise level to a mere whisper for me. If another room location is out, a sound deadening box cover can be a option.

Dale

 

[toolznthings]

Hi,

Ran a " test " for you using a very small compressor I use for a finish nail gun.
The compressor puts out 5.5 cfm , 3.7 cfm free air @ 100 psi and only has a 2.5 gal tank.
With the fog buster set at 10 psi at the reservoir I timed the run cycle. In approximately two minutes the compressor came on twice, but easily pumped back up and stopped each time.
The only time I run the fog buster above 15 psi would be in a deep bore on the lathe or pocket on the mill.
Hope this helps you out.
PS : could not find any info on cfm usage doing various searches.

Brian

 

[blighty]

Dale....

dont have another room to put the compressor in, did think about putting it outside, but then you have the neighbour problem with noise. have seen people on YT making these
deadening box. the noise reduction on some of them was quite impressive.

if i can find a small ish compressor i might go with the deadening box and put it under the mill's table.

toolznthings......

thx for the research, exactly what i was after. ill start having a hunt for a compressor to match yours. might go a bit over. better to have a bit more than a bit less i think.

 

[toolznthings]

Hi Blighty,

Don't make the mistake I did more than once on my compressor buys. Make sure you up size more than you think you need. Would hate to see you get to small a unit and have regets. No need to ask me how I know !

Brian

 

[deverett]

Hi,
snip
Noise issues, my solution is to keep my compressor outside of my shop room. This lessens the noise level to a mere whisper for me. If another room location is out, a sound deadening box cover can be a option.

Dale

If using a sound deadening box, remember to have an air circulation system otherwise the compressor will overheat in time.
I have a small Aldi compressor in a plywood box lined with carpet and the noise level is 'acceptable'. For cooling I use a small 40 watt duct fan, sucking air in at the front of the box and exiting higher up in the front (because I don't have any space to the side or behind). I can use the compressor for about 45 minutes before is is necessary to let it cool down.

Dave
The Emerald Isle

 

[bb218]

I have a Bijur mist unit, it will allow me just apply a very fine mist with no air to a blast of air. Also has a built in solenoid so I can turn on and of with my controller.

Mike

 

[blighty]

I have a Bijur mist unit, it will allow me just apply a very fine mist with no air to a blast of air. Also has a built in solenoid so I can turn on and of with my controller.

Mike

that reminds me. need to look into solenoid stuff. would be cool to get mach to turn it on. would also be nice not to get covered in coolant when you first turn the pump on and not realize the nozzle is pointing strait at you.