This one was suggested by my friend, Sian, who does technical translation, which is how she came to know the meaning of these two rather lovely words. Or one of them, anyway. I’m not sure where mandrills come in to technical translations! I am kind of betting that I never get a search through for these … let’s see if I’m proved wrong!
This is a matter of knowing your spellings, in essence.
A mandrel (only one el, mind, and yes, I did have to look it up. But it is in my fairly standard Oxford Concise English dictionary, so it is a real word of some kind of common usage!) is a shaft or spindle in a lathe, which you use to fix wood (etc.) while it’s being turned. It’s also a rod, cylindrical, around which metal (etc.) is forged. And, it’s a word for a miner’s pick, too!
A mandrill (two ells), is a large type of baboon, found in West Africa, with a red and blue face and, if male, a blue bottom.
Um … “The mandrill, being a blue-bottomed monkey, was not hugely keen on using the mandrel to help it turn the wooden banisters, but it was a helpful sort of baboon, so did its best”.