Comment by sidewndr46
18 hours ago
I'm unsure what your definition of "cheap" is for WD-40 but I find it to be very overpriced. If I need a universal lubricant that is readily available and cheap, I just use used motor oil.
18 hours ago
I'm unsure what your definition of "cheap" is for WD-40 but I find it to be very overpriced. If I need a universal lubricant that is readily available and cheap, I just use used motor oil.
> If I need a universal lubricant that is readily available and cheap, I just use used motor oil.
Why? Used motor oil is, well, used. It contains metal particles from the engine and combustion byproducts, which is why it was replaced in the first place. Granted, most lubrication applications aren't the marvels of precision parts moving at high speed that a modern engine is so can probably make do with poorer oil, but still.
You can buy industrial lubricants in bulk for pretty cheap so that unless you use huge quantities of it, it shouldn't make much difference.
As an aside, my aunt's husband worked more or less his entire career in a heavy truck repair shop. And he had an oil burner heating his house (you can see where this is going, eh?). So he got used engine oil for free, the shop was happy to get rid of it as disposing of it properly cost money. I think burning used engine oil was illegal already back then due to the pollution, and nowadays I think they have some government mandated accounting system to ensure that the same amount of oil is sent to proper recycling as comes in.
You're right about getting industrial lubricants in bulk for cheap. But I don't need 55 gallons of lubricant. I'd never use it all nor do I want to store it.
Used engine oil isn't really suitable for lubricating an engine anymore but it's fine for a temporary lubricant of a drill bit, some random hinge on a gate, or stubborn bushing on a piece of equipment. Engine oil is only really replaced on an engine because at some point it degrades enough that things like oil film bearings in the crankshaft would start to fail. A bushing on something like a small dump trailer doesn't rotate at 2300 rpm.
I thought WD-40 was more a solvent than lubricant
The WD in WD-40 stands for "water displacer." It makes water go somewhere else. Secondarily, it is a solvent, and it's great for dissolving glues, like the glue used to affix government-issued tax licenses to automobiles. It's not really a lubricant, but in a pinch it can temporarily function as one.
I like Swiss army knives, but they collect lint and gunk from my pockets. I use WD-40 to dissolve gunk, and to drive out water after an ultrasonic bath, but I lubricate with the light machine oil used for barber's clippers.
It is a blend of oils. Light oils evaporate (like kerosene does for example), and dissolve thicker oils and grease. Oils displace water in general and once in the surface pores they prevent water from getting in there again, a mixture containing light oils flows in easier and does that better. Being predominantly a light oil it is a poor lubricant, but it is better than nothing, and can flow in crevices where thicker stuff would not.
It is really simple and there is no magic.
The name took off as a brand and completely different stuff from the 40th iteration of a Water Displacer formulation is being sold under it as well.
> It's not really a lubricant, but in a pinch it can temporarily function as one.
That's wrong. WD-40 is a literally a lubricant mixed with a solvent that makes it very fluid so it can enter small interstices, the solvent then evaporates quickly, leaving the lubricant in place.
There's not a lot of lubricant in there compared to a pure lubricant, because the solvent takes a significant share of the volume, but it's still a lubricant once the solvent dries up.
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Yeah, it mostly evaporates and only leaves a thin film behind. It's better than nothing if there's no lubricant in place, but will actually make things worse if there is a functional lubricant in place.
Used motor oil isn’t sold in aerosol cans with a little red straw for precision application. You aren’t just buying the liquid.
I just bought a little bottle I can squeeze from harbor freight. One drop is usually enough. If I need to I can give it a big squeeze and get a bunch out.
On the other hand I can't dip a pin or whatever in an aerosol can like I can a bucket.
Not with that attitude you can’t!
Motor oil doesn’t spray too well.
(Yes, you can buy bulk wd-40 liquid and put into a branded or unbranded sprayer)
Sparying oil is bad - it just collects dust. Oil what needs oil only
I’m okay with dust on the overspray. Keeps the salt off.
Isn’t that carcinogenic?
Isn't a pretty wide range of products you'd use for this? I guess vegetable oil isn't and it works fine. Fluidfilm I don't think is either. I wear PPE for this reason however.
If you want a clean cheap petroleum oil, chainsaw bar oil will work. Generally I prefer the generic Tractor Supply bar oil because it seems a lot stickier than walmart's version which seems more like hydraulic fluid to me. But either way it is cheap because in a chainsaw 95% of it is just sprayed all over the place anyways.
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Only if it's used and only if it's ingested.
Clean motor oil is not actually that harmful if swallowed - it only carcinogenic because of all the metals and carbon it builds up when in the motor.
"I just use used motor oil."
Used, not clean.
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The aditives in a new engine oil are carcinogenous and toxic already.