Re: Drilling Lubricant
 

This is strange. I see people recommending that I do NOT use WD40 as a cutting fluid.

I find this strange because at the 3 shops I have worked at, two private and one government run, they have all used WD40. Sure, there is cutting oil too, but none of the machinists use it. They are like, 30 year veteran machinists, and they all use WD40.


I understand the argument, and if I ignore my experience, I would think that WD40 is bad. But out of my own 3 years of machining, I find that WD40 outperforms any cutting oil. I dont know why. It just cuts faster, especially on aluminum. And, I have never had problems with it lighting on fire.

BTW, isnt only the propellant in WD40 really flammable? The oil burns, sure, but it takes a lot of heat. When you're cutting at high rates, it just evaporates, and thats what you want it to do.

However, for long CNC cuts, we just use water flooding. For everything else, its WD40.

Any machinists had any bad experiences with WD40? I'm curious on this one...

I dont know. Maybe I'm just a hack with machining :P

Re: Drilling Lubricant
 

RIDGID Thread Cutting Oil is available from KBC Tools by the quart and the gallon.

Re: Drilling Lubricant
 

Ever try to unstick a stuck nut and bolt by first spraying it with WD-40, and then when that doesn't work taking a blow torch to it??

No??

Well.. I haven't either, but I have seen it done, and it's not pretty. WD-40 is indeed flammable as a liquid form, and probably as you said even more so when in gas state coming out of the can.

As far as whether or not it will burn while machining, I'm not sure cause I haven't had personal experience with it, but I'm sure if you are milling hard enough and at a slow enough speed and the heat and friction builds up, I'm sure the flash point of the WD-40 could be reached, and it could be ignited.

Just a guess so far though. Anyone want to test this theory in a safe and controlled environment?

Re: Drilling Lubricant
 

In high school, we almost always used WD-40 for cutting (both in shop class and in FIRST) ... rather than it being the last resort, any other cutting fluid was deemed that. I never realized that it was potentially hazardous to your health, flammable, and not the best solution. :o

Thanks for the info!

Re: Drilling Lubricant
 

We've used it extensively as a cutting fluid (in hindsight we should probably find something else), and though it smokes like crazy, we've never ignited it on a mill. However, from an alumni's joke on someone, a TIG welder has no problem lighting it up...

Re: Drilling Lubricant
 

I've used WD40 when I ran out of cutting fluid while threading pipe and drilling. It definitely is not as good as a good threading fluid like Hercules dark lard sulfur based oil. There will be more tool wear and less cooling with WD40. The water soluble cutting fluids are better for automated machining where it is constantly applied.

Re: Drilling Lubricant
 

I've never tried it, but I wonder if butter is any good? Depending on the butter it might be able to hold metal shavings to keep an area clean. Or, maybe I'm just hungry.

Re: Drilling Lubricant
 

Well, i'm not sure the butter would be any good, but I could be wrong. A cutting fluid does several things as I understand:

1. Keeps a bit cool, therefore keeping it from being tempered, etc. To do this, the fluid needs to stay intact and consistant, i.e. not burn at low temperatures, like butter does. Ever leave butter in a hot pan and come back 10 seconds later? Doesn't last too long.

2.Lubricates the two surfaces in contact to a degree. Just enough to allow cutting, but also help preserve the cutter. Butter might do this.

3. Clear chips. I think that a good fluid actually tries to move chips, keeping the cutter clear so it can cut without obstruction. Probably not.

4. Be fluid. Until you melt butter, it's very hard. Sounds like a good explanation to me.

The other problem is that if you didn't clean it all up, it'd rot after a while.

And then there's the saftey issue. I'd be worried that the 9th graders would constantly be trying to lick the endmill. Not good, if you know what I mean...

But, in a tapping situation, I had never thought of this. If I was in a pinch, I might do it, but it'd be an absolute last resort.

Re: Drilling Lubricant
 

After reading this I thought of something funny that happened to me.

At work I was getting ready to power tap the ends of several pieces of Bosch profile with a 12mm tap. After getting the Milwaukee drill set up with the tap I went into the machine shop asking for a bottle of tapping fluid. Now most of the machinists there keep plastic spray bottles and containers on thier machines or carts and not the original containers. They don't mark most of the plastic containers after transferring contents into them. One of the guys handed me a container and told me "Here's what you'll need". It was blue in color.
After I shot some of it into the ends of the profile and on the tap I preceded to tap the profile as it was clamped to the bench. I'll be darned if the stuff he gave me wasn't the best stuff I've used so far! Usually I'd have to clean the tap off after each hole, instead the chips fell right off the tap as the drill spun in reverse as I removed the tap. The tap stayed real cool also and it had a wierd but yet familiar smell I couldn't place right away. After doing two dozen or so holes he came running out with another container with blue liquid in it. Apparently he realized he gave me the wrong container. I had been using diluted Dawn as tapping fluid! :yikes:

Re: Drilling Lubricant
 

Im a fan of Cool Tool II, its not water based so it doesnt rust the machines if not cleaned up right away. It does have an odd odor- it smells kinda like chicken to me, but its not dangerous. Ive known old school machinists to recomend kerosene for aluminum, never having tried it, i wouldnt know- but acetone works for tapping. Im not a fan of the oils for tapping Al because the chips just get stuck to the tap and i get stuck with a sticky dirty mess. I usually machine Al dry anyway unless im making a large hogging cut or drilling an excessivly large hole. If youre making the Al extrememly hot, youre probably feeding too fast- thats my theory.

Re: Drilling Lubricant
 

We have been using a blue tapping wax for our aluminum cutting. You rub it on the cut line or hole mark and on the blade or drill. The wax melts as the heat builds. The cut time is reduced and there is no fluid splash. It excels at tapping aluminum.

I found it in stick form from McMaster part number 10275K32.

Re: Drilling Lubricant
 

While thats genrally true, especially for manual milling, CNC milling with streaming coolant, the coolant does more than cool the tool and the workpiece, and flush chips. Chemical reactions occur under the pressure and heat at the cutting edge, that help preserve the tool edge and many other things.

http://www.blaser.com/download/Publication_Sept02.pdf is a good read on the subject. So using the coolant/lubricant can let you go faster not juts because the cooling properties, but because of other things also.

Its not just a case of if something is slippery it makes a good cutting fluid.

Re: Drilling Lubricant
 

Youre right, i was refering only to manual machining.

Re: Drilling Lubricant
 

WD-40 is essentially Stoddard Solvent (can you say paint thinner?) with a small amount of light oil (like 3-in-one oil) and other additives. Is says so on the Material Safety Data Sheet.

Kerosene is sometimes used for tapping aluminum and brass. You can use lard or bacon grease for steel - some add powdered graphite to the mix. I've heard people recommend using milk for tapping copper, probably because of the butterfat. You will be safer and your tools will last longer if you use the correct machining/tapping fluid.

Plain water will keep the tool cool, but doesn't provide any high pressure lubrication.