I was told NEVeR to use WD40 on K. Machines Use a good quality sewing machine oil, or some of the girls use a gun oil. Don't know why, just decided to follow that suggestion
Each person must make their own decisions on what products to buy and use.
I personally have used WD-40 for a great number of years, after "meeting" it first (if I remember correctly) in the Royal Navy, where it was used all over the Helicopters we carried to remove salt, remove water, remove and prevent corrosion, and to free up items that were siezed.
So when a part of a fine mechanical device is siezed, WD-40 will often loosen up the part, as will many other good products will also do.....but some of them are also very poisonous, MM oil for a classic example of one with appalling poisons in it.
Which is why MMO cannot be ordered/bought in many countries, due to those poisons.
Also, it has also well documented that MMO will cause some fine mechanisms to fail, as for example, it has been documented as the cause for bringing an aircraft down!!! (I posted detials recently on KP!)
Also, it is very clearly documented on many websites that Brother, for instance, does not recommend MMO at all, as it ruins most of the plastic parts of Brother KMs.....so be warned! I have personally no idea what it does to other makes of machine, as I only use Brothers.
WD-40, although I would not recommend drinking it,
is allowed to be imported into almost every country in the world!!
Which makes it very attractive for people who live in such countries where other products are completely banned.
I have heard "word of mouth" only, that WD-40 is bad for KMs, but up to now, no real facts......nbody has ever supplied any verifiable FACTS proving its bad, EXCEPT where people have forgotten to lubricate afterwards with a quality oil....!
But please continue to NOT use it, that is your own peronal decision, but please be so kind as to not "bad mouth" it in any way shape or form.....many thanks.
If you do try it out, do remember it is not a "longterm" lubricant for some machines, and a good quality oil is still required before usage.....I recommend a good sewing machine, or gun oil....its knowing this small but important point, that makes the difference. But of course it is the same for all penetrating oils, as they are not intended as a lubricant, because they are generally very "thin", to help easy penetration.
I hope this helps you further to decide on how to make your own decision in this matter!!
PS. If you wish for supporting weblinks for any of the points I have made, I can supply them for you, its no bother.....