Thursday, October 10, 2013

Hearth Melting / Axe Modeling with Jack McAuliffe!

Me striking for Jack in his Worcester, MA shop
Alright so Jack McAuliffe and I go way back.  We grew up in the same little town in New Hampshire, and the first conversation we ever had was in 4th grade when we made a deal to build a lightsaber together.  "We've got all the parts.  We could totally do it.  We just need some crystals, man."

I'm not sure exactly what happened after that, because we don't have any lightsabers, but we do have these incredibly awesome lives where we get to work and learn and make things and meet people who do the same things and different things.  We live in different cities and have totally different lives but we have a lot of really awesome things in common and it's really cool to have a good friend grow in a craft with you, especially if they knew you before something that's such a huge part of your life now was just a potentiality.

One thing we worked on together a little bit this summer was hearth melting.  He recently embarked on a journey across the vast United States where he stayed with such bladesmithing luminaries as Dave Delagardelle of Cedarlore Forge and Jeff Pringle, learning and making and doing travelly things.  After that he spent five months in Australia and New Zealand, sailing and cliff-adventuring, battling giant spiders and learning the sand-smelty ways of a smith named Anton A., and brought his knowledge back to the New England for further experimentation. 

So, this past summer, we built a few small melting furnaces from bricks, ground clay/mud, and some fibrous plants.  For air we used a small shop-vac on the blow setting and a tuyere of 1" black pipe.  For fuel we used hardwood charcoal.  Our only real process references were Jack's teachings from Anton, my observation of Jesus Hernandez's hearth melts in Baltimore in March, and online tutorials by Zeb Deming and Lee Sauder.  We had, of course, plenty of steel scrap to melt, mostly mild steel cutoffs and railroad spikes, and were more or less going for blade steel, so we positioned the tuyere as best we could imagine would foster the correct reducing atmosphere to allow the nearly-molten steel to absorb carbon from the charcoal.

Contoocook River bog iron
We were working on this in the town we grew up, where I'd also like to say that we found some pretty good chunks of what's definitely bog iron in the river about a tenth of a mile from my dad's house.  We didn't use it as we weren't doing a direct-reduction bloomery smelt, but we'll use it for that eventually, especially considering that bog iron is the most historically-corroborated Scandinavian Iron Age source of iron ore. 

Our first run was pretty inconclusive due to a bad tuyere height, so the right part of the furnace failed to meet the right temperature.  We fixed that on the next couple of runs and came up with several very solid, dense remelt pucks, which we compacted with a sledge on a stump and split up to bring back to our respective shops down south in Mass.

Me standing on our third stack
One of the awesome things about hearth melting is that it's a completely historical process, using simple technology to achieve fascinating ends.  It's absolutely essential to consider in thinking about pre-industrial steelmaking and blade production, because it allows the recycling of scraps which were once much more valuable and scarce than they are now.

The other incredibly cool thing is that its product is entirely indistinguishable from bloomery material.  Hearth-melted steel, heated with charcoal and air in a stack of organic matter, is going to be exactly the same as anything made in an iron-age furnace.  It's an easy way to practice the working of period material without the humongous learning curve of direct-reduction bloomery smelting from ore. 

Dense hearth puck and old NH-made wrought/steel axe
Here is a photograph of our second hearth-puck which we split to experiment with individually.  Like I said, it was very solid for its size, which was a great thing to feel.  It's about five inches in diameter and 1.5" thick, shown here next to a #2 Underhill Tool Co. wrought iron splitting axe with a welded-in high-carbon bit, made in Nashua, New Hampshire sometime between 1850 and 1890.  It was a pretty awesome find Jack made at our local flea market.  Because of the connection and obvious awesomeness of the axe, Jack has called his bladesmithing enterprise Underhill Edge Sword Co.  Below is a sword blade of his inspired by the ambiguously Roman or Germanic pattern-welded spathae, probably from the 4th century, discovered in the Nydam Mose bog burial in Denmark.  It features what's called a 'piled' high-contrast core and stacked san-mai edges of steel in wrought iron jackets.  Pretty badass and authentic. 

And, as I promised, some tantalizingly coy model shots with the irresistible axe:


For those of you who can't get enough, here's one more:


  1. I think old age techniques are something that is fueling the fire for what many would consider the "revival" of traditional blacksmithing and bladesmithing. Wonderful article, my friend. Your friend got to work with David from Cedarlore, what an awesome experience! Your sax that you recently posted about is simply beautiful. I have been practicing forgewelding, but I get some bad welds. I need far more practice. Do you mind if I mention your blog in some of my blogging as a reference? There's a great wealth of old world knowledge here.

    1. Thank you Benton! By all means; I would be flattered if you referenced me. My friend Jack did go on an epic journey last year where he stayed with David for a while (and says he's pretty much the nicest guy ever).

      If you're having trouble forge-welding, I suggest you look for tips and ask for help on The entire community is super welcoming and unbelievably knowledgeable! Best of luck and thanks again! Will you give me the link to your blog?