WD40 is not a very good long term lubricant.
While it may be sufficient for hobbyist that use their dials lightly or for display on a shelf, a telephone company would have never used it for dials placed in regular service since they did not want dials used on a daily basis to be consistently returned to the shop for re-lubricating and adjustment.
While I have used WD40 myself when working on a heavily seized and encrusted dial, once I had it moving freely, I flushed it away and applied normal lubricating procedures for long-term preservation and use.
Almost any professional who knows lubricating oils thinks WD40 is terrible.
Here are a few random comments from others:
"This is a common misunderstanding. It does have an oily texture, but it does dry out and it won't keep things lubed up forever. Now, cleaning a surface that had oil or grease on it with WD-40, and then using some Tri-flow is probably your best bet.
WD-40 is a great substance, for a lot of stuff. If anything is stuck, rusty, dirty, sticky, hardened, etc... WD-40 is probably the answer."
It's a great hand cleaner too when you are working in the garage. I like to prewash my hands with just some WD40 and a towel before going inside to finish washing with soap.
I second this. I would also add that when you put up a Christmas tree and get sap all over your hands, WD-40 is fantastic at getting it all off easily. Source: used it twice this year (setup, take down).
Popular Mechanics-
The "wd" in WD-40 stands for "water dispersal."
One of the more dispiriting facts of consumer life is that panaceas don't routinely live up to their promises.
Sure, sometimes you get penicillin, a product that needs no introduction, but other times you get Dr. Ebeneezer Sibley's Reanimating Solar Tincture, an elixir alleged to restore life in the event of sudden death.
And then there's WD-40, a putative fix-all that boasts uses ranging from driving moisture from a flooded motor to killing roaches to breaking in baseball gloves to reviving drowned cellphones. Such is its pop-cultural ubiquity that it even co-stars in a well-known handyman apothegm: "If it moves and it shouldn't, you need duct tape. If it doesn't move and it should, you need WD-40."
But is WD-40 really toolbox penicillin? Or is it the snake oil of lubricants?
To find out, we culled various products recommended for use in five common DIY jobs and pitted them against WD-40.
Treating a bicycle chain with WD-40 is about as profitable as trying to extinguish a grease fire with a wet haddock. Because its light lubricating properties aren't sufficient to cope with the torque and speed generated by pedaling, WD-40 won't help much. And because water dispersal can degrade heavier existing lubes, it could actually make things worse.
The end result after pitting it against five common jobs-
Final Tally
THE WORLD: 5
WD-40: 0
Despite the final tally, WD-40 is not a complete zero. What it lacks in job-specific excellence it makes up for with across-the-board flexibility. In addition to being serviceable in a wide range of tasks (Bob Cornwell uses it to drive moisture from the electrical connectors between trucks and trailers), it is also good at cleaning (Jacques Gordon confirms that it's aces at removing bumper stickers). But its best ability may be discouraging rust. After all, it was first used in the 1950s to prevent corrosion on the Atlas missile. If it's good enough for an ICBM, it's good enough for those garden shears.
More Comments...
YSK WD-40 is a solvent, not a lubricant. Mistaking it as a lubricant will only mask the problem, not solve it.
It's listed on WD-40 official website as a myth. They say that it's technically a lubricant, it's job is to clean things. For some tasks around the house, WD-40 offers the job of both cleaning and lubricating.
However, using WD-40 on a job that specifically needs lubrication will not yield the results you desire.
I only recently learned this and wish I knew it before wasting time spraying door hinges to keep them from squeaking. You should have 3-in-1 oil along side of your WD-40. Just as versatile.
EDIT: The point of the YSK is that if you're like me, you grew up thinking WD-40 and oil can be interchanged. Most likely, taught to you by an authority figure (my dad taught this to me) so you never second guessed it. You start using it everywhere because, hell, that's what you're taught and that's all you know. You don't read the directions because, heck, you've been using the stuff for years. I didn't know that WD-40 and oil were different until last week and I'm in my 30s. Yes, WD-40 is still great to use on a lot of things. Just don't hang your hat on it for things that are dangerous.
EDIT 2: And the pun was completely unintentional! Thanks for all of the clarifying comments. I'm not a DIY wiz...just from what my dad taught me. Seems like there is a lot of confusion on my part on the definition of a lubricant and solvent. In either case, I'm glad I know now that WD-40 ≠ grease and are not interchangeable.
