So, I'm pretty new to the craft (less than 6 months serious work) and I really wanted a hot cut hardy tool.  I do some steel shopping at my local scrap yard and I was lucky enough to come across some 4140 elevator pins.  1-1/4" diameter.  I had a a few extra hours on Friday sooo... I got to bangin... I used an angle grinder to make a square nub on the end so I could grab it with my tongs. I made this with a 3lb cross peen and a file for final profile on the cutting head.  I never thought that moving that much steel by hand would be possible.  My shoulder still hurts and I broke my hammer but I did it.  Hahaha. I heat treated the blade portion but didnt bother tempering as I felt the heat from hot materials would ruin any tempering I do. I would love some feedback. Please and thank you.  

Better than my first! 

Do temper the edge. If (when) you miss a hit, you don’t want your hammer to be softer than your hardy. 

Looks a lot better than my first one. You can sharpen it with a bench or angle grinder. I usually just draw the edge temper to blue with a propane torch or in the forge.

It weel cut!

I suggest on your next that the shaft be long enough to stick out the bottom a bit. Then, should your hardy tool get hung up in the hole, a quick tap will set it free

Looks good from here. Beveled on one side makes it a "Butcher" rather than a hardy. I generally prefer to cut stock on a butcher it leaves one side of the cut straight the other side being the pinch off. Butchers are also used for setting shoulders and isolating areas for specific shapes. That type butcher isn't sharp the edge is rounded so it doesn't leave a cold shut / stress riser. 

Leaving the shank longer than the anvil tail or portable hardy hole is a really good idea. If you make the shank loose enough it can't bind in the hardy hole the bottom tool will rattle in use and that's not a good thing. If you make it fit it can cock and bind, bumping it out with a tap from below is easy and doesn't require something to use as a punch. You can just use a piece of steel that fits the hardy hole as a punch and bump it out too. I'd just rather not have to grab another tool if I can avoid it.

Frosty The Lucky.

Nice job.  Rest the shoulder.

Looks good.  my first, I'm told looks stone age

 

Id normalize that edge. 4140 Will hold up just fine against hot steel, and leaving it hardened and tempered runs the risk of damaging your hammer face or taking a chip out of the hot cut.

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