The very first Vintage Sewing Machine I bought was a very sad and rusty La Vincendora 128. I used two whole spray cans of WD 40 on it and never got it to loosen up decently. Why?
WD 40 is a water displacement product. It is not a lubricant. It might seem like it is lubing things up but it isn't. When it dries, it leaves a film on the surface which becomes gummy with time. Sort of like dried up KY Jelly. ICK. Use Sewing Machine oil or Tri Flow or Liquid Wrench or PB Blaster. WD 40 has its place but not as a lubricant.
I do use WD 40 in my shop as a WATER DISPLACEMENT tool. If I use a water based cleaner and need to rinse the part with water I will then use WD 40 to displace the water so that the part doesn't rust. I figure a sticky film is better than rust. Then I oil the part with SM oil. (I once used that abbreviation in an email to Betsy who wrote back "What is SM?" Really. True story)
I never used 3 in 1 oil, though. Never.