Please Don’t Try to Sharpen Blender Blades With Eggshells.
I don’t use my standard blender that often, unless I need to purée soup. I use an immersion blender weekly, mainly for dressings, sauces, mayonnaise and other emulsions; sometimes I also use it to make a smoothie or a quick milkshake. It never occurred to me to sharpen the blades of any blender because blender blades are designed for crushing, crumbling and mashing, not cutting and dicing. However, someone has to look for a way to sharpen these little things, because there is a viral hack for this. Unfortunately, the hack is bad.
Type “how to sharpen blender blades” into a search engine and you’ll be rewarded with two types of articles: those that suggest you sharpen and sharpen them just like a knife, and those that advise you to toss in a bunch of eggshells and water. into your blender. Don’t do the latter. It doesn’t make any sense.
What is sharpness anyway?
As we said earlier , sharpening and sharpening are two different things. If you were to look at a blade under a microscope, you would see many tiny teeth on even the smoothest, thinnest blade. These teeth are cutting. When they fail, they cut less cleanly and require more pressure to cut through whatever food you slice. Honing straightens teeth; sharpening creates new teeth by shaving off old metal. An eggshell is not capable of either.
Why won’t eggshells sharpen blender blades?
This is where the wheel really doesn’t need to be reinvented or even slightly modified. According to this 1979 Washington Post article (and common sense), you can’t sharpen a blade with a material that’s softer than the blade itself:
Metal can be straightened with a sharpener. However, it is very important to use a sharpener that is harder than a knife blade or you will end up sharpening the sharpener. Sharpening occurs when a harder material wears away a small portion of a softer material.
Well, nevertheless.
I don’t need to measure the tensile strength of eggshells and blender blades to determine which is harder. I can’t break a blender blade with a quick flick of my wrist, so it turns out I can’t sharpen a blender blade with something that can be broken that way. The only thing you’ll get by throwing a bunch of eggshells into the blender is eggshell paste and maybe slightly duller blades.
Another popular hack is to mix aluminum foil together. Again, this won’t work because the blade is harder than the foil, but it’s also a matter of direction. When you sharpen or sharpen, you move the blade in one direction with deliberate pressure to either straighten existing teeth or shave off old metal to create new teeth. The eggshell in the blender moves in all sorts of chaotic directions, making it impossible to rearrange anything.
How to sharpen blender blades?
I don’t know what you’re mixing that dulls your blades so much. (Unless you’re a Blendtec expert ; then I know exactly what you’re mixing, and it’s a mess.) Cocktails and soups don’t require the clean cut that a freshly sharpened or honed knife provides. However, things wear out with use, and if you’re a heavy blender user, you may of course notice that your blades aren’t blending as efficiently as they used to.
First things first: check with your blender manufacturer. Some, like Ninja , will tell you to “never try to sharpen blades”. If this is the case and your blades are not doing what you want, I recommend contacting the manufacturer and asking for a replacement.
But if you want to void your warranty and want to do it yourself, it’s not that hard: you can sharpen and sharpen blender blades just like you would a tiny knife. Gadget Review can walk you through the process in writing , but this person at Sharpens Best can show you. His videos are rambling but entertaining, and he shows off a few mini sharpeners that make the job even easier. (He starts sharpening at about 5:40.)
Save eggshells for compost or whatever gardeners do with them . Don’t put them in a blender and definitely don’t throw them down the chute – eggshells may not sharpen anything, but they will damage your chute .
Edited on March 1, 2023 at 12:40 pm EDT to add information about the direction of travel and how it relates to sharpening and sharpening.