Your favorite aluminium milling/drilling lubricant?

[nctnico]

In the past decades I have used alcohol-ish liquids (like Spiritus or ethanol) for helping with milling/drilling aluminium but perhaps there is something around which is safer. Any suggestions?

[T3sl4co1l]

In the US, we use WD-40.  Besides Water Displacement, it's the only other thing it's good for!  (Note: it is NOT a general purpose lubricant!)

Tim

[tautech]

Wikipedia says kerosene
https://en.wikipedia.org/wiki/Cutting_fluid

[Jeff_Birt]

For application by hand I would a 10:1 mix of WD-40 and Automatic Transmission Fluid (ATF). The ATF is colored so you can see where it is at and it makes it a bit more viscous. There are also many brands of vegetable oil based cutting fluids. I like to use Kool-Mist when I'm using a mister for application. There are also many brands of misters, some will atomize the spray so finely that it creates a fog of vapor in the air that is not the best thing to breath. I switched a few years ago to the Kool-Mist mister and it was a good decision. I ran the small mill for about 5 hours today and used 250ml of coolant (you mix the Kool-Mist with water.)

[mikeselectricstuff]

I find Servisol switch cleaner works well

[rob77]

i'm lazy and using one kind of cutting oil for everything - actually a cheap one from local hardware store (apparently made in Germany because it states "Bohrol  Schneidol" ) if taking really light cuts to aluminium on lathe or mill then not even bothered to use anything. btw using HSS tools, no carbide.  on the other hand i have a really small lathe (proxxon FD150) and mill (proxxon MF70) and working on small parts only, probably that's why it works for me.

[Lightages]

Almost anything that cools the cutting edge and provides some kind of lubrication will work. You can use WD40, vegetable oil, engine oil, Vaseline, KY jelly, etc. One thing that does not do very well is plain water.

[langwadt]

In the US, we use WD-40.  Besides Water Displacement, it's the only other thing it's good for!  (Note: it is NOT a general purpose lubricant!)

Tim

I've tried WD40 and it is not nearly as good as ethanol, plus it smells and leaves a mess.



 

[SL4P]

Water does it.

[langwadt]

Almost anything that cools the cutting edge and provides some kind of lubrication will work. You can use WD40, vegetable oil, engine oil, Vaseline, KY jelly, etc. One thing that does not do very well is plain water.

with aluminium it is not so much about cooling, it is about preventing the gummy aluminium "welding" itself to the tool so you end up rubbing rather than cutting

[Gyro]

That's the first time I've seen KY jelly advocated as a coolant!

[Neganur]

Isopropanol or IPA or w/e it's called

[Muttley Snickers]

As previously mentioned, I love the smell of kerosene in the morning, and just about any other time for that matter. 

These handy little reference books below are a must have for anyone involved in the art of swarf creation in my view.   

Sutton Tools AU.
http://www.suttontools.com/

[alsetalokin4017]

A9.

It's green, it smells good, and ... it works.

[Lightages]

Almost anything that cools the cutting edge and provides some kind of lubrication will work. You can use WD40, vegetable oil, engine oil, Vaseline, KY jelly, etc. One thing that does not do very well is plain water.

with aluminium it is not so much about cooling, it is about preventing the gummy aluminium "welding" itself to the tool so you end up rubbing rather than cutting

 

[T3sl4co1l]

That's the first time I've seen KY jelly advocated as a coolant!

Reminds me of another thought...

What's the correct feeds and speeds for human flesh?  Do you think all those lucky* machinists with a missing finger might know? 

*There are old machinists, and there are lucky machinists, but there are no old, lucky machinists.

On a lighter note... the correct rate seems to be up to 350 RPM... if you don't believe me, there are websites about it... <verb deleted>ing machines... 

Tim

[nctnico]

These handy little reference books below are a must have for anyone involved in the art of swarf creation in my view.   

For that kind of questions I have some close relatives to turn to. I'm the occasional swarfer and most of what I do is making enclosures for electronics.

Regarding my original question: I think I'll stick to ethanol then even though it means I have to keep the door of the shed open in the winter. I'm surprised by the many answers and even snot (KY Jelly) seems to work  .

[Len]

What's the correct feeds and speeds for human flesh?

I don't know about that, but here's a guy who has done some videos on machining vegetables.
(Seems like he uses WD-40 for alumin{i}um.)

https://youtu.be/ZZoXcKiHDag

[Mickster]

ISTR Windex being mentioned over on CNCzone but I can't remember the exact situation....

[radar_macgyver]

I now use Kool Mist mixed with water, but before I bought the spray nozzle I used a squirt bottle filled with denatured ethanol. The squirt action knocked off the swarf, and the alcohol evaporating cooled down the work. The trouble was the headache from the ethanol fumes.

[langwadt]

I now use Kool Mist mixed with water, but before I bought the spray nozzle I used a squirt bottle filled with denatured ethanol. The squirt action knocked off the swarf, and the alcohol evaporating cooled down the work. The trouble was the headache from the ethanol fumes.

headache? you are supposed to lubricate the parts you are milling, not yourself  

[DenzilPenberthy]

Reminds me of another thought...

What's the correct feeds and speeds for human flesh?  Do you think all those lucky* machinists with a missing finger might know? 

The figure quoted to me when I did my chainsaw qualification was roughly 4.5 ft/sec. I do not wish to ever find this out the hard way!!!!

[John Coloccia]

I like Boelube. I was turned onto it when I was doing experimental aircraft building. Works great on aluminum.

[rx8pilot]

Tap magic aluminum for manual stuff. After 10 years of CNC machining - this is the stuff I came to rely on for the 'touch-ups' in manual machines. You only need a tiny amount so I got a nice dispenser to accurately place a few drops at the cutting location.

http://www.tapmagic.com/product/2/tap-magic-aluminum

[HighVoltage]

I bought a small bottle of A9 Relton cutting fluid for Aluminum a long time ago and it will probably last a lifetime.
I am not sure what is in it, but it works very well.

http://relton.com/a-9-aluminum-cutting-fluid/

[LaserSteve]

Green A9,  although I'll use bulk WD40 liquid in an emergency. I make prototypes out of 6061 and brass as part of my job. I'll use Tapmagic for tapping, there is some really good additive in there for tapping high Silicon Aluminum or "gummy" Aluminum.

Steve

[nctnico]

Thanks again for all the suggestions! I got a project involving quite a bit of work on aluminium. I'll go and hunt down some tap magic (I'll need to tap around 100 holes) and some Relton A9 cutting fluid for drilling. As a side node: I still need something convenient for tapping into aluminium manually. I'm too afraid to use something mechanical (like a cordless drill) since I'll be working on 250 euro heatsinks (each!) and hate to leave a broken tap in it.

[rx8pilot]

FWIW - you can use either one for drilling, milling, tapping. I have never used A9, but the tapmagic works as a general purpose cutting fluid for small jobs. For aluminum, I generally use forming taps that compress and flow the material instead of cutting it. No chips and it does not take much power to do it. You can tap with no pecking - just run the whole depth and never clear a chip. Reduces the chance of broken taps from chip clogging and re-cutting.

You do, however, use a different hole size for forming taps. It is always a slightly bigger hole so you need to get a forming tap chart if you go that way.

[nctnico]

Those forming taps look like a great solution to me and I never knew they existed until now 

[P90]

Green A9,  although I'll use bulk WD40 liquid in an emergency. I make prototypes out of 6061 and brass as part of my job. I'll use Tapmagic for tapping, there is some really good additive in there for tapping high Silicon Aluminum or "gummy" Aluminum.

Steve

The original TapMagic with the smell that would give me a headache,
 worked so much better than the later environmental friendly mixture. 

[radar_macgyver]

As a side node: I still need something convenient for tapping into aluminium manually. I'm too afraid to use something mechanical (like a cordless drill) since I'll be working on 250 euro heatsinks (each!) and hate to leave a broken tap in it.

How about a tapping stand? I've had good luck with those on plates (< 5mm thick). As long as the original hole was drilled perpendicular to the surface, the stand will help keep the threads square to the plate as well.

[alsetalokin4017]

I got pretty good at tapping by using this technique:

-Clamp workpiece in drillpress or mill vise and locate hole to be d+t
-Drill with correct size drill for tap (work up in stages if it's a big hole)
-Without moving or unclamping workpiece, put the tap in the chuck
-Apply a bit of A9 for aluminum or TM or whatever
-Start drillpress and turn off (you just want the inertia of the spindle, not driven by motor)
-Lower tap into hole and let the inertia of the spindle+chuck to "thread" the tap into the hole
-Be ready on the brake so as not to go too far or fast
-Blow out chips with compressed air
-Reverse DP rotation and lift tap out of hole under power

It takes some practice and you might break a tap or two while learning, but once you've got the technique down it will save tons of time, and you always get perfectly tapped holes this way.
 
(Of course you have a broken tap extractor kit on hand, don't you?)   

[HighVoltage]

Tapping aluminum with a hand drill requires a really good (and expensive) tap.
If you are using a really good tap, the cut out material will come out to the front and will not be in the way and will not create any additional friction.
Using a slow speed and a little bit of fluid will create great cuts.

I have a set of tapping tools just for Aluminum and will never use them on any other material
Also one set just for tapping plastics and this will never be used on metal.
This way, they will always stay sharp and work great.

Here are some pictures
The last one is especially good for tapping Aluminum
But don't be scared to pay a huge price for these.

https://www.hoffmann-group.com/DE/de/hom/Monozerspanung/Gewindebohrer/Maschinen-Gewindebohrer-HSS-E-PM-Hartchrom/p/134270-M1,6

[SeanB]

If you are tapping and want to make 100 or so holes use the roll tap, and buy a good quality set, and with it also order a tap extractor, so you can get the broken tap out if you break it.  A good tap T handle ( racheting type) will also help, and also get a centre bit to drill your pilot holes accurately and drill a slight countersink in the surface as well for the tap.  If the tapped hole is over M5 get a countersink mill to get a good edge on the finished holes, and make sure that there are no burrs on the surface. Under M5 the 6mm centre bit does this job in one step.

If you have a harder aluminium alloy use a spiral machining tap, though there hand tapping is really not recommended, as they are spiral and self clearing, but brittle, and are a pain to extract if you break them in a hole. I have a few centre punches made from broken taps.

[WackyGerman]

In my company we still use spirit for drilling and tapping in aluminium with standard drills and taps for steel . I made hundreds of tappings and never had a problem with fitting electrical components

[orin]

If you are tapping and want to make 100 or so holes use the roll tap, and buy a good quality set, and with it also order a tap extractor, so you can get the broken tap out if you break it.  A good tap T handle ( racheting type) will also help, and also get a centre bit to drill your pilot holes accurately and drill a slight countersink in the surface as well for the tap.  If the tapped hole is over M5 get a countersink mill to get a good edge on the finished holes, and make sure that there are no burrs on the surface. Under M5 the 6mm centre bit does this job in one step.

If you have a harder aluminium alloy use a spiral machining tap, though there hand tapping is really not recommended, as they are spiral and self clearing, but brittle, and are a pain to extract if you break them in a hole. I have a few centre punches made from broken taps.

I like to use a regular tap handle and a tap guide - http://littlemachineshop.com/products/product_view.php?ProductID=1963&category=

I get the hole set up as you say, mount the guide in the mini-mill, centered over the hole, then let the spring loading provide the initial pressure on the tap.

[nctnico]

I'm pretty good with aligning a tap without tools but I think I'll get something like this just to make sure because the forming taps seem to be trickier than cutting taps:

BTW the tapped holes need to go into a large heatsink (200x120x120 mm) and they are all blind holes.

[rx8pilot]

I'm pretty good with aligning a tap without tools but I think I'll get something like this just to make sure because the forming taps seem to be trickier than cutting taps:

Definitely true. They are designed to be used with a machine or tapping fixture.

[nbritton]

I just use the pink RV anti-freeze, a/k/a propylene glycol, in my milling machine coolant system. It's like $2/gallon. It's non-toxic, propylene glycol is used as a food additive. Carbide can cut through aluminum like butter so you don't really need a cutting fluid per se, what you need is a coolant. 

https://www.walmart.com/ip/Super-Tech-RV-Marine-Antifreeze/17179674

[tautech]

I just use the pink RV anti-freeze, a/k/a propylene glycol, in my milling machine coolant system. It's like $2/gallon. It's non-toxic, propylene glycol is used as a food additive. Carbide can cut through aluminum like butter so you don't really need a cutting fluid per se, what you need is a coolant. 

https://www.walmart.com/ip/Super-Tech-RV-Marine-Antifreeze/17179674

How wide a range of metals do you find anti-freeze useful for ?

[rob77]

I still need something convenient for tapping into aluminium manually. I'm too afraid to use something mechanical (like a cordless drill) since I'll be working on 250 euro heatsinks (each!) and hate to leave a broken tap in it.

using a tap designed for machine taping and setting the clutch on a cordless drill to low torque (just enough to do the job) never failed on me (usually taping M3 to M5 sizes). if the part is really expensive and i don't want to accept any risk, then i'm going for the 3 pass taping with a set of taps (3 times the same hole with a drill is still much faster than hand taping).

[nbritton]

I just use the pink RV anti-freeze, a/k/a propylene glycol, in my milling machine coolant system. It's like $2/gallon. It's non-toxic, propylene glycol is used as a food additive. Carbide can cut through aluminum like butter so you don't really need a cutting fluid per se, what you need is a coolant. 

https://www.walmart.com/ip/Super-Tech-RV-Marine-Antifreeze/17179674

How wide a range of metals do you find anti-freeze useful for ?

I really only work with aluminum so I don't want to comment on that. I have used it for steel and didn't run into any problems with it.

http://www.engineeringtoolbox.com/propylene-glycol-d_363.html

[nctnico]

I just use the pink RV anti-freeze, a/k/a propylene glycol, in my milling machine coolant system. It's like $2/gallon. It's non-toxic, propylene glycol is used as a food additive. Carbide can cut through aluminum like butter so you don't really need a cutting fluid per se, what you need is a coolant. 

https://www.walmart.com/ip/Super-Tech-RV-Marine-Antifreeze/17179674

I wouldn't be so quick to call any glycol non-toxic. A couple of years ago I had to do some research on which type of glycol to use in a smoke machine. There are lots (I means LOTS!) of different types of glycol and some are very toxic where others are used as food additives indeed. I'm not convinced coolant is needed at low speeds but aluminium tends to clog badly (at least the soft 6060? stuff I usually encounter) so it is more about lubrication at low speeds. Still glycol is something I could try since I still have part of a bottle with food grade propylene glycol.

[CraigHB]

Ethylene Glycol is very toxic.  That's the stuff they put in coolant for engines, though they're getting away from that now.  Propylene Glycol is not toxic at all.  It's used in stuff like toothpaste and baking confections.  So yeah you have to be real careful with glycols and be positive about what you're working with.

I have a small milling machine I use for hobby stuff.  Of course 6061-T6 aluminum is my favorite metal to work with.  I use a real simple cutting oil, three parts mineral spirits and one part mineral oil.  It's super cheap and works well.  Cutting oils sold for machine work with aluminum are like ten times more expensive and are not particularly easy to find.  Mineral spirits you can buy from the hardware store and pure mineral oil you can buy from the drugstore.  I've actually tried WD40, but I like my home brew cutting oil better and it's still a lot cheaper than buying WD40 by the gallon.

[radar_macgyver]

I'm not convinced coolant is needed at low speeds but aluminium tends to clog badly (at least the soft 6060? stuff I usually encounter) so it is more about lubrication at low speeds.

Are you using TiN coated tools? Aluminum tends to stick to this coating. I'm not sure if TiCN is any better, but I've had best luck with uncoated or black oxide coated tools for aluminum.

[CraigHB]

I use cheap HSS bits from China.  The milling bits get a constant flow of cutting oil, but I just use WD40 on the stuff done by hand.  Never had a problem with aluminum sticking to the HSS bits, but they dull pretty quick on stainless steel.  Titanium...forget it.

After reading this thread I think I'll see if I can get some of that tap magic.  Also like the idea of forming taps.  I've done something like that using stainless screws on aluminum, but didn't know taps are made just for that purpose.  I've found formed threads in aluminum are stronger and tighter than cut threads.  That's always good especially for the tiny screws I use a lot with powered models.  There's a bigger difference in strength between formed threads and cut threads with those tiny screws.

[geggi1]

I've been using a mix of polywater http://www.polywater.com/polyplus.html and ethylene alcohole.
It works very well.

[nctnico]

I looked into obtaining Tap magic and Relton A9. Doing that I came across a topic on a machinists forum where several agreed the new formula of tap magic lost most of it's mojo but Relton A9 seemed to be still good. I couldn't find it locally so I had to order it from the US and to offset the horrible shipping costs I bought four 110ml bottles (guess what my father gets for Christmas...). I tried to get a gallon but unfortunately the sellers didn't want to ship to the NL.

[tautech]

I looked into obtaining Tap magic and Relton A9. Doing that I came across a topic on a machinists forum where several agreed the new formula of tap magic lost most of it's mojo but Relton A9 seemed to be still good. I couldn't find it locally so I had to order it from the US and to offset the horrible shipping costs I bought four 110ml bottles (guess what my father gets for Christmas...). I tried to get a gallon but unfortunately the sellers didn't want to ship to the NL.

Be interested to see how that goes....

When I need a drilling and tapping lubricant, Rocol RTD is my preferred:
https://www.rocol.com/products/rtd-compound-reaming-tapping-drilling

[nctnico]

OK I'll post the results but that will probably be around Christmas.

[nctnico]

Today I used the Relton A9 for drilling and tapping and it seems to work very well. Also the forming taps work like a charm! The hole diameter is crucial though. Because I drilled the holes in soft aluminium in one go the first few turns aren't that good due to the hole being slightly larger. I also tried a drill 0.1mm smaller but with that the forming tap seemed to get stuck after a few turns. I didn't want to apply more force to it because a) I don't want to have a broken tap in my workpiece b) the taps are not cheap at over 30 euro each (ex. VAT).

[SeanB]

Those forming taps work extremely well on plastics as well, and make a decent thread. Works well on PTFE rod to make a thread, though you will have to drill undersize there.

[rx8pilot]

Those forming taps work extremely well on plastics as well, and make a decent thread. Works well on PTFE rod to make a thread, though you will have to drill undersize there.

I use them for Delrin (Acetal Copolymer) material all the time - hundreds of thousands of successful threads.

[jonatanrullman]

I actually just use liberal amounts of rapeseed oil from the grocery store, usually applied with a $1 paint brush.
Probably not the best, but so far it has worked alright and it does have a few points in its favour. The price not least. And the (lack of) smell. Also it is of course entirely safe for consumption, not irritating to skin and fairly easy to clean so you don't have to watch out as much.

Cheers

[cdev]

Quick question- I bought these tools as part of a batch of stuff I got at an estate sale some time ago in the hope that I could use them as part of a metal shop. They look like CNC milling tools, can anybody tell me more about them or what the little things in the small box are used for? I don't know the first thing about this but I would like to learn.

Are they for CNC milling of blocks of metal?

[BradC]

Quick question- I bought these tools as part of a batch of stuff I got at an estate sale some time ago in the hope that I could use them as part of a metal shop. They look like CNC milling tools, can anybody tell me more about them or what the little things in the small box are used for? I don't know the first thing about this but I would like to learn.

Are they for CNC milling of blocks of metal?

The units in the top pticure are fly cutters, and the tips look like interchangeable tips for circlip pliers.
It'd be interesting to see the taper on the fly cutters to get an idea of the spindle they are designed for.

On topic, I've always used Kero for ally, but I was chatting to an old machinist yesterday who swears by diesel. I couldn't hack the smell myself, but he reckons the extra couple of gnats worth of lubricity makes a noticeable diffference particularly on a small / underpowered machine.

[langwadt]

https://youtu.be/Z8XLkmNORkg?t=13m36s

[BradC]

https://youtu.be/Z8XLkmNORkg?t=13m36s

I did the cylinder head on my current Volvo using a home made HSS fly cutter on my neighbours mill.
Used Kero as the lubricant for the Aluminium and Glenmorangie as the lubricant for the machinist.

[rx8pilot]

Those single point fly cutters are used for manual machines in general. They are very slow which is the opposite dream with CNC which usually uses a 5-7 flute indexable face mill that can make a mirror flat surface at amazing speeds.

Sent from my horrible mobile....

[cdev]

How do you get all the faces to mill at exactly the right height and angle?

[rx8pilot]

Its a single point that rotates creating a flat plane.

Sent from my horrible mobile....