Ethanol mist for cutting aluminium

[Robin Hewitt]

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?

[cropwell]

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.

Cheers (hic)

Rob

[Tenson]

'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]

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.

[cropwell]

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]

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]

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]

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.

[JAZZCNC]

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.