I’m going to post the process that I’m using to make a chisel from round bar. Two things about this – I’m sure it will be refined as I make more chisels, but it is already practical. Second, this is my sixth forged chisel from round bar and only one of the other five is fully finished. But, I’ve made a lot of chisels hammer tapering flat stock and then affixing a separate bolster, so those two pieces of information is useful. You may get to this point in six chisels total (i doubt it) but if it takes longer than that, I’ve paid my dues and enjoyed it rather than running from the failures and hoping to avoid them.
The point of this, as mentioned in yesterday’s post, is both to get to more forging, but more importantly, to have the chisel made from a single piece of steel. I’m making this chisel out of 115crv3, a relatively plain steel (less plain than 1084, more plain than O1, and miles more plain than A2, for example). I’m using this rod type even though it’s kind of hard to find because I want a chisel that is going to land in the 63 or so hardness range with a solid double temper of 400F, and 0.9% or 1% steel can suck wind a little bit in trying to achieve that and not be a bit chippy. This steel is 1.15-1.25% depending on the melt. I expect to lose a little bit of that as decarb from forging, but not too much due to the induction heating instead of sitting in a hot gas or coal forge. Induction allows you to focus more on the part you’re hammering and heat adjacent areas enough to avoid cracks, but not have to heat a whole blank end to end to upper forging temperatures.
So, unlike most of my very wordy posts, this is going to be more pictures and fewer words. The goal here is just for me to share what I’m doing. The goal in the future is to really get the amount of chisel made forging vs. grinding and filing increased. I’m not there yet, but have made huge strides just in six.
Here is the round bar – 20mm 115crv3 steel. I’m not fully decided yet and have ordered three more bars of the stuff with some smaller, but I think I’ve learned enough thus far to know that I don’t actually need anything smaller because drawing it out is easier than expected. That’s not to say it’s easy – it’s a little physically demanding by hand.
115crv3 alloy rod – sold in the US only in one place and apparently intended as stock for material conveying systems.
The first step is to start drawing the stock out from the bar. There’s guess work here until I’ve got more experience – as in what will yield a chisel between 5/8 and 3/4″ from the bolster down, and hopefully a little over 5″.
I leave a lot more at the tang shoulder because this chisel will have a classic taper with top curvature (eat that CNC), and then use a guillotone to start to establish the tang.
That gets me to this.
You can already see why I like doing this – the bolster does not have to be upset to greater diameter, the basic rod is there and it is high quality, so I know it won’t be brittle or weak.
This is what the guillotine looks like. It’s apparent from this making and others that I will probably want to make a guillotine anvil/bar set that will taper this more into the shoulder and perhaps leave the tang area a little shorter than the 3/4″ flat default. But those are things to learn. I’ve already ordered more 4140 bar stock to make different anvils – this will become a useful tool for a one-man operation.
The guillotine, resting. You lift the top bit and put the work between the bars and then hammer and turn.
To this point is about 15 minutes of heating and hammering. 1/3rd of 1 and 2/3rds of the other. I’m using a 4 pound hammer and am by no means a physical specimen, but I’ve not handed in my man card yet in exchange for looking in the mirror and always-clean pants and hands.
After establishing the roughed tang, I draw out the steel in about the taper that I want to have less some room for grinding and finishing off the outer layer, as well as the expectation that more will come out of the tang area. Not much needs adjusting near the business end, but the tang area is nice to leave a bit to work with as distortion there is a pain.
The last 1/4 to 1/2 inch of this will come off. it’d be nice to have left a bit more on the end, but we’ll live. The objective here is to get closer to straight top and bottom to avoid distortion in the quench later. I will grind the top curvature in, hoping that the warp in the quench doesn’t make that difficult. The actual tang thickness will be ground down quite a bit, but I will probably mark this one with my stamp so there will be some distortion on the blade below the tang from doing that.
It’s slightly wider at the shoulders than the business end, and grinding will deal with that pretty quickly.
Of Making by Hand with Wood and Steel 
The only question I would ask is… Is it drawn rod or is it cast steel billet ground into rod?
Looks like you might have gotten some bad product. It would be interesting to send a sample out for XRF. Silver steel rod is used for many things including drill rod and for linear bearings – both require fine grain, high hardness, and stability.
As a second check, Woodcraft green handle chisels are advertized as made of 115CRV3. Maybe get a set on sale and run a sacrificial lamb through the hardening process to see if it behaves the same.
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It’s drawn stock, annealed and intended to used for linear motion or as a drive shaft. But as you point out, everything I’ve read suggests it won’t get as hard as 26c3 but should actually be more hardenable.
I’ve come to a pretty reliable conclusion that something is wrong with it. It might be short on manganese, because snapped samples show plenty of carbon suspended in carbides, but they also show graphite deposits, which is strange to see.
to ensure it wasn’t my forging just being a bad match for the steel, I cut a sliver off of the rod and found it to be less hardenable than even the forged samples.
On top of that, if you can superficially get a very thin piece to 64 hardness (I can with a high heat and a harsh quench in brine), a single temper of 350F for half an hour brings the hardness back to mid 50s. the spec sheet suggests it should lose 2 points from quench hardness if tempered at 390F, so it’s a dud.
I didn’t question it early enough vs. trying to figure out adjustments to the heat treat process and speed of the quench, but sometimes it’s nice to beat a challenge. You can’t beat one if the actual material isn’t capable of meeting spec, though.
I’ve had defective steel before, but it was poorly dispersed alloying elements. I’ve never had steel that doesn’t harden, but this is already relatively low hardenability steel and if manganese was accidentally shorted, it has no margin for error.
Hopefully my second order of the stuff before hardening steel from the first bar can be canceled – waiting to find out. otherwise, I may experiment with hardening compounds with the first bar just to get some experience with them. I’ve had a can of kasenit for more than 10 years and have been half dying to find an excuse to use it. it will through harden something as thin as a chisel, but it’s not exactly a precise controllable process.
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Just looked up the woodcraft chisels – this steel is German, or maybe it isn’t, the supplier is German. I did notice that you can get round bar of 115crv3 from china for about $650 a ton, which puts the cost per chisel at an industrial level well below $1 per set. It costs me with shipping about $50 to get a 20mm bar, but none of the euro stuff would probably be $650 a ton, but rather multiples of that.
This bar, since it’s a supply item for linear motion, is precision ground, but it’s hard to get away from that if you’re buying at retail because the average customer is working to spec.
At any rate, woodcraft suggests a range of 59-63 which is nutty for 115crv3. the spec sheets all say 64-66 for quench hardness and 62+ for a 200C temper.
But I don’t doubt they can find it in china to drop forge into chisels pretty easily. I’m a little less convinced about how good the quality of it will be if it doesn’t get fully normalized and then thermally cycled, but the chisel set they’re advertising is $38 and there is definitely a chance that if grain isn’t blown up in them and they land at 62 plus, they could be superb.
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the comments on the woodcraft page about distortion in those chisels is humorous š the more typical 0.6 and 0.65% steels are less demanding for a quick process and should distort less. they also usually have a lot more mn to make the quench quality a lot less critical.
yet another person in the knife world has told me that I should expect something easier than 26c3., but of course all of them question my comments about 26c3 being pretty easy to deal with by hand (but it is. Not easy compared to O1, but it’s not that demanding).
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