yikes. I've almost never had that with anything -- but I have felt the siren call of the Hobart Dough Hook
This is an industrial stand mixer (often it has a grating attachment to that round top port sticking out like a pipe end on the top left of the pic) and Hobart is a very popular brand for these machines, which are often nearly as tall as a person
the thing hanging from the mixing arm into the bowl part is a dough hook
it looks like this and spins around mixing the dough
Here is a smaller one, but you can see what it looks like when it goes
So one of my first kitchens, everyone who got shown how to use the enormous 5ft tall Hobart we had, they got some variation of this speech:
"DO NOT reach into the mixer while it's on. I know, you think that now, but you're going to get comfortable around it, it's going to seem like it's moving slow, and you're going to feel like reaching in there to check the dough or something without turning it off. DON'T. DO THAT. One guy a couple years ago went to the hospital with every bone in his arm broken and a dislocated shoulder and it was from reaching into this exact machine we're using today. You're going to feel like you can reach in real quick without stopping the machine, and I'm telling you, turn it off first."
I got that speech too, and sure enough, there came a day when I felt the urge. Which i resisted. But then. Then there started to be reasons to reach in there.
Like maybe the person using the grating attachment hadn't cleaned the port good enough and a couple of strips of grated carrot fell onto the dough, where it would stay sort of oscillating on the top of the dough ball for a little bit before getting sucked down to be kneaded deep into the dough. It's a single button to stop the machine, but, for some reason it just seems like such a hassle, and you've always wanted to do it, c'mon, look how slow it's moving...
So i did. And it was fine! Altho i could see why people get it wrong, what seemed like about a 3 second window actually turned out to be less than a full second once you got your hand down there, and there really wasn't as much space as it seemed like there was, and the angle you had to go at did slow you down just a little... But now that i knew all that, i should be fine to do it as long as i was careful, right?
Then one day it happened. I must of brushed ever so slightly against the metal of the dough hook. It is shaped and moving in a way designed to draw material in toward the center and down and it tugged my hand ever so slightly in and down.
Which would have been fine but I was already touching the dough, so it tugged my fingers into the dough just enough for it to get the slightest grip on them, which tugged my hand in just enough to get caught between the hook and the dough which gripped it surprisingly hard and yanked my hand down and in a circle like having someone hold your hand tightly and spin in a circle and all my joints locked up against each other painfully so fast!
Luckily I was able to get my arm out before I suffered more than a sore shoulder, hurt elbow, and sprained wrist and sprained finger... but things went from totally fine to sheer panic faster than anything i've ever experienced.
Even so, only a week later and barely recovered, I caught myself just before i reached my hand into the dough bowl while it was on, the siren call of the Hobart singing strongly still.
So many people felt it. I heard so many close call stories. Some models like the Hobart 660 comes with this wire cage safety guard now, and I guarentee it is 100% because no matter how you warn people, they can't resist reaching in while it's running