Lost me at calling WD40 lubricant. Although I do agree with the premise, it is very satisfying when it is easy to open your door.
I feel like this is one of those internet myths someone once said and now everyone just blindly repeats.
My only thought is that there's cheaper generic brands but regardless it's a great tool for the job.
Btw, about a year ago I read that copper grease is absolutely the best for this purpose but I'm still waiting for a hinge to become squeaky so that I can test that.
I know it's for keeping water away. I use it for that purpose on my swords. But why isn't it a lubricant? Maybe it's not the best, but it can serve that purpose.
The spray, composed of various hydrocarbons, was originally designed to be used by Convair to protect the outer skin of the Atlas missile from rust and corrosion.[11][12] This outer skin also functioned as the outer wall of the missile's delicate balloon tanks.
> It acts as a lubricant, rust preventive, penetrant and moisture displacer.
and the article is in the category of "Petroleum based lubricants"
So it seems just because it wasn't intended as a lubricant doesn't mean it can't be be.
Ask anyone who works professionally with machines and they'll tell you WD-40 is a temporary lubricant at best.
I do note that lubrication is actually complex. Soap feels plenty slick in general, but if I try to shave with it, certain soaps give very poor results. So, of course, not everything slick and oily is going to work for lubricating machines.
But when I rub soap on wood screws, it works just fine in that context!
Sure professionals use WD40 when appropriate. Sure WD40 lubricates great, for seconds to minutes (before the volatilies evaporate off, thus the WD40 smell), less well after that (somewhat gummy residue) and might well stop a creak. But won't lubricate nearly as well as oil or grease or last as long.
If you take a properly lubricated widget and as part of regular maintenance you spray WD-40 on it, it's less lubricated, might be fine for a bit, but it's mostly a cleaner and water displacer. Ideal in some situations for cleaning, before you apply a lubricant. WD40 does leave something behind, maybe better than metal on metal, but it's gummy and pretty far from what I'd consider a lubricant.
Sure in some cases chewing gum, soil, or sand can reduce friction, I wouldn't call them lubricants though.