It happens with some people and not others so I think its the way some of us knit or turn the work.
I have multiple Knitpicks sets. Any screw in type needle can come undone, but the key helps. IMO though using a piece of grippy shelf liner works so well I've not had one unscrew since! I use the key for leverage and put the grippy on the right needle and tighten. Try that before you buy new needles.
ETA - I do like the KP wood needles a lot. I mostly use the NP just as personal preference to metal.
Last edited by Jan in CA : 04-10-2013 at 03:31 PM.