Ask HN: Are Dishwashing Machines Bullshit? | Hacker News

I doubt it. I have a dishwasher but don't use it. I wash and dry dishes by hand. It takes no more than 10 minutes to wash and dry two persons' dishes and cookware. I often cook and wash dishes at the same time!

But I've been washing and drying dishes since I was a child and my early years of conscripted dish washing were spent learning to optimize washing and drying procedures. So I'm very fast and efficient.

For a family of more than 4 persons, a dishwasher likely is handy though by no means a necessity. In the absence of a dishwashing machine, one person washed and a second dried.

As for the "pre-clean" phase - soak dishes and utensils in a sink or bowl of warm soapy dishwater for 5-10 minutes to loosen/remove most food residue. Then the dishwasher (wo/man or machine) will work properly.

But the true conundrum is this: in all my years of washing dishes both for myself and for commercial firms (college jobs as dishwasher) I have always washed knives - sharp knives. Yet I have never cut myself on a knife or a sharp utensil. I have learned that I can grab a handful of sharp knives from a soap-and-water filled sink blindly and quickly without fear of cutting my hand.

Something is going on that I don't understand: possibly the soap modifies surface tension around the blades and prevents them from penetrating my skin. This happens whether my hands are dry or soaked by hours of dish washing. Any ideas what is happening here?