The irony of course is that they deliberately make some parts out of plastic so they break before the rest of the machine does when you're misstreating it.

I’ve had the same experience, with paper shredders - particularly the Fellowes brand, in the UK - which all have a nylon (possibly some other plastic) cog, somewhere to overheat, then break.

In this case, I think it's so they break before the bones in your hand do.

They’re built out of plastic because it’s $0.02 cheaper than a metal part and 99.9% of them last through the warranty period.

It’s not deliberate that they make stuff that fails, they build stuff that lasts only as long as it needs.

There's a single nylon gear. The rest are made of metal. They've been using a sacrificial worm gear since the 1960s.

KitchenAid switched to all-metal gears on their high-end models fairly recently. In the past, all models had a nylon gear, but the new high-end mixers use electronics to protect the motor.

Some plastic parts are intentional / sacrificial. Even so, the old mixers were definitely built to last.

Plastic gears have lower friction and don't require greasing. They aren't really bad on their own. The problem is you can't find replacement parts when they break.

Get a FDM printer (filament), and get FreeCAD.

You'll need digital calipers as well. You can cheap out for $20, or get Mitutoyo's for $200.

A scanner's also nice in scanning a geometry thats flat, but not required.

Just with a 3d printer and a meager ket, you can replace most current commercial crap in a few hours, and have the replacement as a file you can call on any time.

That's how I'm handling this "throw away culture" shit. I'm replicating what I need and throwing away the actual broken bits.

Reduce, Reuse, REPAIR, Recycle. (Hint: the manufacturers want you to forget the 4th, hidden R.)

If these things break all the time why isn't someone producing them and selling them?

Because they are all custom sizes. And they don't break often. It's like 10 years after purchase where there aren't too many other owners looking for parts and the original company doesn't support it anymore.

Not all KitchenAid stand mixers are made the same: https://old.reddit.com/r/Cooking/comments/a6510b/wife_loves_...

TL;DR: The Pro Line is what you want. These have higher-wattage motors and are made with all-stainless steel. This is important if you mix heavy things like doughs or meats frequently, as these materials tend to stress and shear plastic more easily.