Council Tool Boy's Axe 2.25lbs Chops Seasoned Blue Gum Experiment

[BluntCut MetalWorks]

As purchased: 2.25 lbs head, 1080 steel, edge hardened ~55-58rc, 25 degrees slight convex grind, ~40 degrees edge, 28 inches curved handle

Will modify it to experiment specs: full hardened 62-63rc, 17 degrees flat grind bevel, 30 degrees edge

Blue Gum Characteristics: Janka 2370 lbf, MoR 135MPa, EM 18.8GPa (https://www.wood-database.com/blue-gum/). Here is my recent video - chopping blue gum: youtu.be/7S7-v-UNXa8

Appreciate any advises/thoughts - should I consider before go forth with this?

 

[FortyTwoBlades]

You seem to be making a lot of very square blows to the wood. For proper cutting performance you'll find better results cutting diagonally, at about 45°to the wood. Also, as-purchased it's likely the hardness is closer to 52-54 RC.

 

[BluntCut MetalWorks]

You seem to be making a lot of very square blows to the wood. For proper cutting performance you'll find better results cutting diagonally, at about 45°to the wood. Also, as-purchased it's likely the hardness is closer to 52-54 RC.

Thanks. I'll do more 45* angle chops, perhaps easier to do so with a lighter 2.25 lbs axe head. You are most likely right about the hardness, since many *as purchased* axe reground edges to 17*, they failed (rippled, rolled and chipped) when chopping seasoned blue gum log.

 

[Christopher_2]

• ANSI Standards call for bit hardness of Rc 45-60, at least ½ inch back from the cutting edge. Council Tool internal standards call for tempered bit hardness of Rc 48-55 and we target 1-1/4 inches from the cutting edge. The poll and eye walls are not hardened and remain in the as forged condition.

This is on their website.

 

[FortyTwoBlades]

• ANSI Standards call for bit hardness of Rc 45-60, at least ½ inch back from the cutting edge. Council Tool internal standards call for tempered bit hardness of Rc 48-55 and we target 1-1/4 inches from the cutting edge. The poll and eye walls are not hardened and remain in the as forged condition.

This is on their website.

Yes, I'm aware. I retail and regrind their products and based on my experience in grinding other axes and edged tools of certain hardness, about 52-55 is where I'd say most of the heads I've handled have behaved like. Which makes sense, since that's right within their stated range, and softer heads around 48 are basically putting some over-tempered anomalies as "within spec" to reduce failure rate and therefore keep costs low. Erring overly hard would lead to breakages, and thusly limiting how high you extend the acceptability threshold makes sound sense, so they're more permissive at the softer end where the edge holding will suck but it's going to dent rather than chip if subjected to failure-inducing conditions. However, it's definitely uncommon for their heads to run quite that soft.

 

[BluntCut MetalWorks]

• ANSI Standards call for bit hardness of Rc 45-60, at least ½ inch back from the cutting edge. Council Tool internal standards call for tempered bit hardness of Rc 48-55 and we target 1-1/4 inches from the cutting edge. The poll and eye walls are not hardened and remain in the as forged condition.

This is on their website.

Thanks. Well, low 50's RC is sure easy to file but no fun chopping blue gum using a thick (huge speed bump) edge, hence will experiment with much thinner edge geometry.

Yes, I'm aware. I retail and regrind their products and based on my experience in grinding other axes and edged tools of certain hardness, about 52-55 is where I'd say most of the heads I've handled have behaved like. Which makes sense, since that's right within their stated range, and softer heads around 48 are basically putting some over-tempered anomalies as "within spec" to reduce failure rate and therefore keep costs low. Erring overly hard would lead to breakages, and thusly limiting how high you extend the acceptability threshold makes sound sense, so they're more permissive at the softer end where the edge holding will suck but it's going to dent rather than chip if subjected to failure-inducing conditions. However, it's definitely uncommon for their heads to run quite that soft.

True that 48+rc steel can bust up any woods given adequate edge geometry. However chops dried woods with thick geometry, where re-bounce might jarring one's teeth

 

[FortyTwoBlades]

Yes, for typical steels and heat treatments I like about 57-ish, generally. Mostly because it's still able to be filed with good quality files in the event of damage.