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matt-b2
25-10-2015, 04:06 AM
Hi,

Has anyone here got any experience using ethanol delivered via a mister system when high-speed cutting aluminium? I understand that's what Datron use in their machines. At the moment I'm using WD40 which works but makes a horrible sticky mess when mixed with aluminium chips/dust and tends to stink the workshop out. I also have issues with the WD40 separating in the mister reservoir (the bottom of the tank ends up with white fluffy looking stuff floating around in it).

Are ethanol fumes an issue? Where can I economically source ethanol, in appropriate form, a few litres at a time? So far I've only been able to find bioethanol (the purity of which I'm unsure about) and methylated spirits (which probably smells worse than WD40) in bulk.

Cheers,
Matt.

phill05
25-10-2015, 05:46 AM
Hazard Communication Sheet ETHANOL C2H5OH Ethyl Alcohol DESCRIPTION Clear, colourless, mobile liquid with characteristic odour; m.p. -130o C; b.p. 79o C. Miscible with water. CAS: 64-17-5. UN number: 1170. HEALTH HAZARDS IRRITANT: Irritating to the eyes Eye contact with liquid causes pain and severe irritation. May cause chemical conjunctivitis and corneal damage. Exposure to high vapour concentrations causes irritation of the eyes and respiratory tract, headache, giddiness and nausea. Swallowing causes narcotic effects (headache, giddiness, nausea, vomiting with coma and death in severe cases).Repeated excessive intake causes liver damage. Liquid degreases the skin and repeated contact may cause cracking. FIRST-AID Inhalation: Remove from source of exposure. If breathing stops or shows signs of failing apply artificial respiration. Use oxygen if breathing is laboured. Obtain medical help. Skin Contact: Remove contaminated clothing and flush affected area with water for at least 15 minutes. Treat patient as for inhalation. Obtain medical help. Eyes: Flood with eyewash or water for at least 15 minutes. Obtain medical help. Ingestion: Wash out mouth with water. Treat as for inhalation. Obtain medical help. SAFETY HAZARDS INCOMPATIBLE with strong oxidising agents, acids, alkali metals, ammonia, hydrazine, peroxides, sodium, acid anhydrides, calcium hypochlorite, chromyl chloride, bromine pentafluoride, silver nitrate, mercuric nitrate, potassium tertbutoxide, acid chlorides, platinum, uranium hexafluoride, silver oxide, iodine heptafluoride, acetyl bromide, disulphuryl difluoride, tetrachlorosilane + water, acetyl chloride, permanganic acid, ruthenium (VIII) oxide, potassium dioxide. EXPLOSION HAZARD. Forms flammable/explosive vapour/air mixtures. Take precautions against static discharges. Ground and bond containers when transferring bulk material. Use spark-proof tools and explosion proof equipment. FIRE HIGHLY FLAMMABLE. Flash point 12o C. Explosive limits 3.3-19%. For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam. For large fires, use water spray, fog, or alcohol-resistant foam. Use water spray to cool fire-exposed containers. Do not use straight streams of water. Use self-contained breathing apparatus if fire is large or in a confined space.

Christian Knuell
25-10-2015, 08:24 AM
Hi,

Ethanol burns and if you're unlucky you can create an explosive aerosol - but small quantities with good ventilation in a big room are usually no issue.

The trouble starts if the quantity is too large to evaporate rapidly so you end up with a pool of highly flammable liquid or if the machine is in an enclosure or small room with bad ventilation where explosive concentrations are easy to create.

The cost for pure ethanol is mainly a question of taxation - there are no cheap sources for alcohol in food-safe quality. But purity is not an issue for machining.
From a health point of view it is always good to minimize exposure to any vapor - but if you only have the choice between alcohol and other coolants alcohol will usually be the lesser of two evils.

So... be aware of the fire and explosion hazard, keep a suitable fire extinguisher around and never let the machine run without supervision.

Christian

komatias
25-10-2015, 08:47 AM
As the guys said, it is flammable. The vapours can make you drunk and prolonged exposure will blind you. Now in order to get it in any quantity in the UK you need a special license. This is to control the alcohol production for public safety.

There are better ways to apply coolant. WD40 is expensive so i always use a water soluble oil coolant. Have a look at misting systems that have air assistance. They are cheap and work well clearing chips.

magicniner
25-10-2015, 09:16 AM
Straight Paraffin works nicely for soft aluminium.
90/10 to 70/30 Paraffin to 20 weight oil gives good results with a wide range of materials.
You will still need extraction for any mist system which creates any airborne contamination in your workshop,

- Nick

Tenson
25-10-2015, 12:29 PM
I think it's methanol that makes you blind rather than ethanol. Please let me know if you find a source for ethanol I might like to try it for the occasional ali cutting (seems like you can get bio-ethanol for fireplaces). The mess of oil or water is an issue for me too.

Both methanol and also isopropyl alcohol are easy to get hold of but both are very bad for your health so make damn sure you don't breath too much. As little as 250ml consumed can kill.

As for WD40 seperating from the water you need to get a water soluble oil. People call it 'cutting oil' and mixed with water 'white water'. http://www.ebay.co.uk/itm/G-P-Soluble-Cutting-Turning-Milling-Oil-Coolant-White-Water-1-x-1-ltr/250443189387?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%2 6asc%3D33958%26meid%3Dd2567809d59249d29951c36d047d 5c11%26pid%3D100005%26rk%3D4%26rkt%3D6%26sd%3D1115 74149025

magicniner
25-10-2015, 12:40 PM
As little as 250ml consumed of either can kill.


Evaporated into air you could make a huge explosion before you got anywhere near exposing yourself to 250ml ;-)

cropwell
25-10-2015, 01:45 PM
Just a further cautionary note - Ethanol burns with a near invisible flame.

komatias
25-10-2015, 10:49 PM
is this the article the OP is refereing to?

http://www.mmsonline.com/articles/alcohol-based-coolant-offers-environmentally-friendly-machining

Still not a particularly safe way of going about it. I wonder if Krytox would be good for the application though. Low viscosity, low evaporation and water based too.

magicniner
25-10-2015, 11:46 PM
is this the article the OP is refereing to?

http://www.mmsonline.com/articles/alcohol-based-coolant-offers-environmentally-friendly-machining


I doubt it as extraction, containment and fire suppression equipment are stated to be implemented for alcohol use, you wouldn't need to worry about the smell in the workshop if that was or was intended to be the case,

- Nick

matt-b2
26-10-2015, 12:51 AM
Thanks for the responses.

is this the article the OP is refereing to?

http://www.mmsonline.com/articles/alcohol-based-coolant-offers-environmentally-friendly-machining

Still not a particularly safe way of going about it. I wonder if Krytox would be good for the application though. Low viscosity, low evaporation and water based too.
I did come across that article whilst I was researching into the matter.

I appreciate ethanol has its dangers - I think, first and foremost, I need to get the ventilation in my shop sorted, no matter what I'm using for coolant.

Robin Hewitt
26-10-2015, 09:42 AM
The problem with ethanol is that the Government tax it to hell and back.

If you cut it with methanol to make it poisonous and pyridine to make you throw up, you can escape the tax.

You could spray it on to a tool tip but I have to wonder why. Are you sure you have the right chemical? :confusion:

cropwell
26-10-2015, 10:51 AM
If you have to use ethanol, then use a good single malt. Avoid Ardbeg as it has too high a phenolic content and could cause a build up on the end of your tool.:toot::toot:

Cheers (hic)

Rob

Tenson
26-10-2015, 05:10 PM
'Meths' or 'Methylated Spirit' is mostly ethanol with a drop of methanol to make it undrinkable. Surely a lot healthier than pure methanol or isopropyl which I mentioned ealier.

Hallettoil
28-08-2016, 04:58 PM
Ladies and Gentlemen

Please...do take very seriously the health and safety aspect of using any type of misting coolant.

Apart from the said flammability issues, the slightest mist , even unseen can be breathed in unnoticed and once in your lungs, there WILL come a time when consequences will manifest themselves.

Vent/extract any form of mist. DO NOT breath it.

Any form of Oil/Chemical on the skin is not good and wise after the event is too late.

If you are using coolants where there is potential skin contact, follow the instructions, Wear protective gloves or at least a skin wet (if necessary) or dry barrier cream and if using hand cleansers, in the main will de-fat the skin so use a conditioning cream.

Those of you that will be expecting cracking skin when the weather turn cold will know what I mean

50 years in the Oil Industry, I could write a book but if you have any issues... feel free




Hi,

Has anyone here got any experience using ethanol delivered via a mister system when high-speed cutting aluminium? I understand that's what Datron use in their machines. At the moment I'm using WD40 which works but makes a horrible sticky mess when mixed with aluminium chips/dust and tends to stink the workshop out. I also have issues with the WD40 separating in the mister reservoir (the bottom of the tank ends up with white fluffy looking stuff floating around in it).

Are ethanol fumes an issue? Where can I economically source ethanol, in appropriate form, a few litres at a time? So far I've only been able to find bioethanol (the purity of which I'm unsure about) and methylated spirits (which probably smells worse than WD40) in bulk.

Cheers,
Matt.

mekanik
28-08-2016, 06:59 PM
Hi Guys
Anyone using this
http://www.exair.com/en-US/Primary%20Navigation/Products/Cold%20Gun%20Aircoolant%20Systems/Pages/Cold%20Gun%20Applications.aspx
Seems a far safer option.
Mike

Hallettoil
28-08-2016, 07:14 PM
Hi Guys
Anyone using this
http://www.exair.com/en-US/Primary%20Navigation/Products/Cold%20Gun%20Aircoolant%20Systems/Pages/Cold%20Gun%20Applications.aspx
Seems a far safer option.
Mike

Hallettoil
28-08-2016, 07:21 PM
Mike

This looks rather good. An exceptional potential alternative to a serious problem.

Certainly for the home workshop maybe worth considering. Not seen the price though...look before a leap!

Hallettoil
28-08-2016, 07:25 PM
NO....Ever seen a Wine-o ? The "Urban dictionary" suggests a person who like excess wine...but in my experience, it is a Tramp who drinks Meths to excess to achieve oblivion.... but with all the added after effects! POISON.

Hallettoil
28-08-2016, 07:34 PM
I see that some folk tend to use coolants. Oil in water emulsions and maybe think that these are less harmful.

Please bear in mind that apart from the chemicals and OIL within, there is an extremely powerful anti-bacteria and fungicide which again in mist can be very harmful. Even fully synthetics will have these.

Don't be thinking you are safe...just don't be breathing it and you will be.

cropwell
28-08-2016, 07:48 PM
Ethanol is the alcohol we drink and in moderately low doses can cause delusions of adequacy. Methanol, on the other hand is a poison which can cause permanent nerve and brain damage at fairly low doses. Methylated spirit is Ethanol with 10% methanol, violet dye and pyridine, which makes it taste horrible.

However, the most dangerous part of ethanol is that is very flammable and burns with an invisible flame and an ethanol mist would be an explosive mixture.

I like the idea of cold air - but I wonder what volume of air it needs to get enough temperature drop through adiabatic expansion to be effective.

matt-b2
28-08-2016, 11:27 PM
I've given up on mist coolant - It might seem the more convenient than flood coolant at first glance but my experience has taught me that it causes more problems than it solves.

1. It doesn't matter what sort of droplet size you're getting from your mist system, if you're using a high speed spindle, the droplets atomise as soon as they hit the cutter and fogging becomes unavoidable. Decent forced ventilation becomes a necessity unless you want to end up with some sort of lung disease or an explosion.

2. Depending on what cutting fluid you are using and the humidity of the climate you are in (the UK is quite humid), the air supply to the mist system will need to be suitably desiccated to prevent moisture getting into cutting fluid reservoir. Moisture can end up emulsifying with the cutting fluid causing it to clump up and cause blockages.

3. In order to clear chips effectively, mist systems get through a lot of air - be prepared to put up with a lot of noise from your compressor, make sure its up to the duty cycle and can deliver the flow. My old compressor (now dead) would run pretty much continuously whilst the mill was running. As I did not have a separate room for it, this was incredibly irritating and didn't do my electricity bill any favours. Ultimately, I think the demands my mist system put on my compressor lead to its premature death.

No doubt, there are plenty of people out there who have had better luck than me using mist cooling, but I'm done with it. I also appreciate that it is not always practical to use flood coolant on some machines. In my case, however, fitting flood coolant isn't a problem and the resultant mess is easier to tame than atomised coolant floating about the shop, getting into all sorts of places it shouldn't. Running flood coolant is also quieter, more effective at clearing chips and uses less power.

With regards to just using cold air, I've never had much luck cutting aluminium dry. I use uncoated carbide tooling and regardless of what speed I'm cutting at, I always end up clogging my cutters without some sort of lubrication present.

Matt.

magicniner
29-08-2016, 11:41 AM
I use uncoated carbide tooling and regardless of what speed I'm cutting at, I always end up clogging my cutters without some sort of lubrication present.

Have you tried single flute cutters?

Hallettoil
29-08-2016, 05:01 PM
As a snippet of useless information. Paraffin has been traditionally used in machining, cutting and forming Aluminium, BUT... it is, as you know inflammable.

In the home workshop if you are to be machining Ally regularly, you may well see if you can obtain EDM Fluid/Dielectric Fluid used in Discharge machines.

I have seen this on Ebay at 55 for 25 litres delivered and it is what is know as.. De-Odourised Kersosene.

The flash point is actually increased which makes it a little more friendly and you could try adding maybe 2% of Rape Cooking Oil. You would have to experiment with this.

This would increase further the flash point whilst giving you an added lubricity additive. I can't guarantee that at some point you may be close to flames so keep a fire extinguisher (powder) handy.

Should you ever be unfortunate enough to have flames, remember that the vapour can get through the powder and can jump across to an ignition source so keep your third eye sharp.

This product is used in hand cleansers and again, be aware of skin and air passages and I don't mean the drafty entry!




I've given up on mist coolant - It might seem the more convenient than flood coolant at first glance but my experience has taught me that it causes more problems than it solves.

1. It doesn't matter what sort of droplet size you're getting from your mist system, if you're using a high speed spindle, the droplets atomise as soon as they hit the cutter and fogging becomes unavoidable. Decent forced ventilation becomes a necessity unless you want to end up with some sort of lung disease or an explosion.

2. Depending on what cutting fluid you are using and the humidity of the climate you are in (the UK is quite humid), the air supply to the mist system will need to be suitably desiccated to prevent moisture getting into cutting fluid reservoir. Moisture can end up emulsifying with the cutting fluid causing it to clump up and cause blockages.

3. In order to clear chips effectively, mist systems get through a lot of air - be prepared to put up with a lot of noise from your compressor, make sure its up to the duty cycle and can deliver the flow. My old compressor (now dead) would run pretty much continuously whilst the mill was running. As I did not have a separate room for it, this was incredibly irritating and didn't do my electricity bill any favours. Ultimately, I think the demands my mist system put on my compressor lead to its premature death.

No doubt, there are plenty of people out there who have had better luck than me using mist cooling, but I'm done with it. I also appreciate that it is not always practical to use flood coolant on some machines. In my case, however, fitting flood coolant isn't a problem and the resultant mess is easier to tame than atomised coolant floating about the shop, getting into all sorts of places it shouldn't. Running flood coolant is also quieter, more effective at clearing chips and uses less power.

With regards to just using cold air, I've never had much luck cutting aluminium dry. I use uncoated carbide tooling and regardless of what speed I'm cutting at, I always end up clogging my cutters without some sort of lubrication present.

Matt.

cropwell
29-08-2016, 05:03 PM
Cutters for ali need to be Open Architecture to allow chips to clear, single flute allows this, but this guy (Roy Kloss) does a range of cutters for ali have a look - http://www.sorotec.de/shop/Cutting-Tools/END-MILLS/

I am not endorsing Sorotec but he has a good range and I have been satisfied with his service. The cutters are probably sourced from China - but faster delivery if you are in a hurry, otherwise you might find the same on Alibaba.com.

Cheers,
Rob

Hallettoil
29-08-2016, 05:04 PM
BY THE WAY... upon heating ...Rape Oil can be gummy (Chip fat residue) be aware of this too

cropwell
29-08-2016, 05:17 PM
Rape Oil can be gummy (Chip fat residue) be aware of this too

You don't have to heat it for it to go off. I tried it as a coolant on my lathe, it got everywhere and went sour and sticky, took bloody ages and hard work to clean it up.

Hallettoil
29-08-2016, 05:27 PM
It is a vegetable oil and is totally unsuited to the task as you say. Some vegetable oils can actually do the job but they do require a certain "tweak!"

I did say... : add to Deod Kero at say 2%.


You don't have to heat it for it to go off. I tried it as a coolant on my lathe, it got everywhere and went sour and sticky, took bloody ages and hard work to clean it up.

matt-b2
29-08-2016, 06:25 PM
Have you tried single flute cutters?
I've been using 2-flute cutters. Not tried single flute yet.

Billythefish
29-08-2016, 10:05 PM
You can definitely do it. You probably also need to run it in conjunction with some sort of extraction, filter, return system. A few things to consider. First of all you dont use much with a minimum quantity system. You dont want to be breathing to much so it is sensible to suck out of the work area and filter/recondense. You could make a system to do this. There are many advantages....

JAZZCNC
29-08-2016, 11:15 PM
With regards to just using cold air, I've never had much luck cutting aluminium dry. I use uncoated carbide tooling and regardless of what speed I'm cutting at, I always end up clogging my cutters without some sort of lubrication present.

Matt.

Well your doing it wrong then. I cut dry pretty much all the time using Carbide tooling with just touch of air and odd squirt of coolant.

Your most likely cutting too Shallow. Carbide likes to be worked hard.
Another Myth is that single and Twin flute cutters are needed for Ali. 3 flute work perfectly well and allow higher feed rates with more DOC.

My Standard setup is 3 Flute serated edge roughing cutter followed with 0.35 finish pass with Twin flute. The Rougher allows quick stock removal with high DOC.

Billythefish
29-08-2016, 11:39 PM
Second dry cutting aluminium with carbide. I use 2 flute. I never use lubricant. You need to go fast and dont be shy :-)

With mql probably provides a slightly better surface finish and longer tool life..

matt-b2
30-08-2016, 03:00 AM
Well your doing it wrong then.
Hi Dean - I have no doubt in my mind that you're absolutely right. I'd love to run without any coolant, I've seen plenty of videos of other machines (yours included) happily munching through aluminium without any coolant present, so I know it must be possible, but I've not achieved it yet. Clearly I need to experiment more. So far, I've tended to play it safe by running plenty of coolant just because, for me at least, it leads to less disasters, even if it's a sub-optimal way of doing things.

Matt.

mekanik
30-08-2016, 09:44 AM
Hi Matt
Have a look @ this.
https://www.youtube.com/watch?v=ifMn6pHXLMM
Regards
Mike

Billythefish
30-08-2016, 12:37 PM
Ooooh... I think he is definately close to the edge of what that tool will take.

All good fun :-)

interesting video, cheers!

matt-b2
31-08-2016, 11:10 AM
He certainly seems to be pushing that endmill pretty hard - Not sure my spindle/steppers would be up to that although I think I can push them a lot harder than I currently do.

In the next couple of weeks, I'll find some time to stick a block of 6082-T6 on my machine and play with the cutting parameters - I've done that in the past to land on a set of figures that work okay with plenty of coolant. I think it is time to revisit the experiment with an aim to push my machine harder both with and without coolant.

I'd quite like to experiment with different endmill geometries too (i.e. number of flutes), but I haven't got the cash to be forking out on loads of different endmills right now, so I'm probably stuck testing with 2-flute tools.

Matt.

Billythefish
31-08-2016, 11:37 AM
Carbide 2 flute seem to work great for alu in my experience. With or without coolant..

Boyan Silyavski
31-08-2016, 12:11 PM
Olive oil work perfectly for threading, better than specialised oils. I am threading a lot of aluminum and brass. Emulsify it with water , mist it and prepare your salad.

Billythefish
31-08-2016, 12:18 PM
Interesting. Couple of small possible problems. You have to clean up well immediately - oil will go off and smell, water will rust your machine. That is the attraction of a liquid with no water...

Chaz
13-12-2016, 09:34 AM
He certainly seems to be pushing that endmill pretty hard - Not sure my spindle/steppers would be up to that although I think I can push them a lot harder than I currently do.

In the next couple of weeks, I'll find some time to stick a block of 6082-T6 on my machine and play with the cutting parameters - I've done that in the past to land on a set of figures that work okay with plenty of coolant. I think it is time to revisit the experiment with an aim to push my machine harder both with and without coolant.

I'd quite like to experiment with different endmill geometries too (i.e. number of flutes), but I haven't got the cash to be forking out on loads of different endmills right now, so I'm probably stuck testing with 2-flute tools.

Matt.

I'd like to revive this slightly old thread.

I have flood on my Triac, it works well but I had the residue / mess it leaves over time.

Id love to cut dry if possible. Since I've upgraded to a 1.5 KW AC Servo Spindle, I may also take some test cuts with smaller (read, cheaper) endmills and see what I can do before I break them.

How do Datron manage with Ethanol cutting without the health / risks?

magicniner
13-12-2016, 09:37 AM
Extraction, extraction and some more extraction ;-)

Chaz
13-12-2016, 09:43 AM
Extraction, extraction and some more extraction ;-)

So in a home / garage environment, Ill need to build something for this? Not sure what the costs / technicalities are for this.

I could continue to do Flood on my Triac however my new machine will not have Flood, well, not planned for. I may reconsider this.

Cold air needs too much air, Ive looked at this before. I dont think its a DIY option.

So Id like to know what options we have for 100% dry cutting. Clearly its possible .....?

magicniner
13-12-2016, 10:09 AM
Even if cutting dry you will need to move chips and vacuum isn't even close to air for getting chips out of the way in holes and slots, so why not look at something like Boyan's solution to add a little lube to your air, then you can use a good bathroom extractor to keep the mist from filling the workshop,

- Nick

Chaz
13-12-2016, 10:54 AM
Even if cutting dry you will need to move chips and vacuum isn't even close to air for getting chips out of the way in holes and slots, so why not look at something like Boyan's solution to add a little lube to your air, then you can use a good bathroom extractor to keep the mist from filling the workshop,

- Nick

So best to look at fog buster or similar? I built my own but limited success with it.

Boyan Silyavski
13-12-2016, 01:07 PM
With mist and fumes collector and filtration

Example:
http://www.clarcorindustrialair.com/Industries/Industrial-Filtration/CNC-Machining


PS. If you do it properly similar to mine, it DOES NOT mist. It spits small droplets, not mist. Thats why its called Foggless

Chaz
13-12-2016, 02:13 PM
With mist and fumes collector and filtration

Example:
http://www.clarcorindustrialair.com/Industries/Industrial-Filtration/CNC-Machining


PS. If you do it properly similar to mine, it DOES NOT mist. It spits small droplets, not mist. Thats why its called Foggless

Thanks, can you link the one you use please? I recall you made your own?

Boyan Silyavski
13-12-2016, 02:49 PM
Thanks, can you link the one you use please? I recall you made your own?

video here #19 (http://www.mycncuk.com/threads/10337-Milling-creating-a-smooth-end-finish-in-a-slot?p=85967#post85967) and details here#21 (http://www.mycncuk.com/threads/10337-Milling-creating-a-smooth-end-finish-in-a-slot?p=86003#post86003)

Chaz
13-12-2016, 02:56 PM
video here #19 (http://www.mycncuk.com/threads/10337-Milling-creating-a-smooth-end-finish-in-a-slot?p=85967#post85967) and details here#21 (http://www.mycncuk.com/threads/10337-Milling-creating-a-smooth-end-finish-in-a-slot?p=86003#post86003)

Thanks, appreciated.

camhguh
13-12-2016, 07:33 PM
On the subject of coolant, has anyone used this brand for aluminium?

Soluble Metal Cutting Oil Coolant White Water Fluid

http://www.ebay.co.uk/itm/Soluble-Metal-Cutting-Oil-Coolant-White-Water-Fluid-1-Litre-1L-/250443189387?hash=item3a4f93cc8b:g:Q4YAAOSw6n5XrGJ 7