How to Harden Mild Steel? (Impossible!)

So they say it's impossible to harden mild steel. Well, here's how to do it... (hint: start with "mild" steel that isn't really "mild" steel.) Tip: When grinding metal ALWAYS use a good filter/respirator to protect your lungs from particles. Here's a link to the model I ordered from Amazon: http://amzn.to/2DBfpAk (Disclaimer: I have an affiliate account, so if you make a purchase using this link I will receive a small commission.) A couple of weeks ago I made a cleaver/wood chopper using a scrap of structural or "mild" steel. For that project I used a 4.5 inch angle grinder as my only power tool and I showed how to put a decent age on a knife made of mild steel. An edge that WILL chop and cut wood without going dull... at least for a while. But I noticed large bursts coming from the sparks while grinding that scrap of steel. That's usually an indication of higher carbon content so for this video I'm testing to see if that steel can actually be hardened and tempered. NOTE: I haven't been posting as often as I'd like because of upgrades and technical issues, but regular schedule of 3 to 4 uploads per week should resume very soon. In the meantime, check out my blog at: www.fargofx.com It's pretty weak right now, but I'm planning to do a lot more with it in the new year. If you enjoy DIY blacksmithing, bladesmithing, metal work, and random "how to" projects please consider subscribing and watching a few of my other videos. Cheers! Forging a post apocalyptic survival hatchet from rebar:    • Forging a Post Apocalypse Survival Hatchet...   How to make a Kydex Press:    • How to make a kydex press and a knife shea...   Forging a camp hatchet from 1/2 inch steel plate:    • Forge a camp hatchet from half-inch steel ...   $2 Snake Catch Pole from PVC and Paracord:    • $2 Paracord and PVC Snake Catcher!   Review: Harbor Freight Machete:    • $5 Harbor Freight Machete: Good deal or Ga...   My brother, GeographyCzar does a lot of videos on scientifically testing ammunition. Here's a link to his channel...    / geographyczar   Audio Attribution: "EDM Detection Mode" by Kevin MacLeod is licensed under a Creative Commons Attribution license (https://creativecommons.org/licenses/...) Source: http://incompetech.com/music/royalty-... Artist: http://incompetech.com/ Cologne 1983 Josh Kirsch/Media Right Productions "You're free to use this song and monetize your video." Destructoid MK2 "You're free to use this song and monetize your video." NOTE: We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.