I am having trouble removing the key from the lock.
Should I spray with WD40 or not?
Yep, free it up with wd-40, then flush it out with a solvent, let it dry and lubricate it with graphite powder.
Hi Bb,
Inox is really good for unseizing things, you can get it at Bunnings in a spray can.
I have Inox and Silicon Spray on board , the silicon is for the plastics, like the Delrin sheaves in the blocks , and Inox for any metal. It's a protectant as well as lubricant, so after you've finished you can leave a film on turnbuckles and nuts/screws suchlike, it really stops your metal getting that funny corroded sheen.
SB
Most lubricants( spray can ,wet penetrating types) will free up and lubricate a lock. Graphite powder may not free up a seized lock as you may be unable to get the graphite to penetrate . However, to lubricate and maintain a working lock, graphite powder is often the best choice because it is a dry lubricant and it wont attract dirt.
For locks that are not frozen I use
www.bunnings.com.au/wd-40-specialist-150g-anti-friction-dry-ptfe-lubricant_p6100410
It penetrates past the pins to lubricate and waterproof the springs and once it dries it leaves a teflon film more slippery then graphite.
For frozen locks I use WD-40 multi-purpose first then once it dries out I use WD40 specialist with ptfe