(and a more general discussion of natural vs synthetic)
Introduction & summary
In 2014 we commissioned production of our ceramic scythe stones with a local potter, and Benjamin Bouchard of the Baryonyx Knife Co commented that he was interested in having some ceramics made industrially. Some discussion ensued about the benefits and perceptions of synthetic vs. natural. In 2015 we started making our own natural whetstones ourselves, about which Ashley Vido gave us a glowing review: “It quickly became my favourite stone”, she wrote.
Some months ago, in response to what I took to be Benjamin ‘teaching me how to suck eggs’ in regard to the properties of whetstones, I blustered, “Lecture me about whetstones when you’re producing Ashley Vido’s favourite stone”, or something to that effect.
Not too long after, Benjamin released his ‘Arctic Fox’ whetstone, commissioned from an abrasives manufacturer, and commented, “It’s quickly become my favorite stone.” Hmmm, familiar turn of phrase, thought I…
And then the one Benjamin sent for me to try out, arrived. While I would never attempt to speak for Ashley (who as far as I know has never laid eyes on an Arctic Fox), I have to say that Benjamin has met that challenge – produced Ashley’s favourite whetstone – at least in one respect: in terms of what it does to steel, with several uses on a number of occasions, I’m unable to pick the difference between a Tassie Tiger and the Arctic Fox, at a cursory inspection. I haven’t gone to any great lengths to do a side-by-side comparison of the two stones on ‘identically-peened’ blades to see which holds an edge longer, nor gone to any level of magnification except for interest’s sake, but both stones can cut quickly with a relatively fine finish, which is all the more unusual in a synthetic scythe stone.
So, if you’ve come here because you’re thinking of spending some of your hard-earned cash on one, and you’re wanting an answer to whether you should, well… yes… yes, you should. It’s a very effective and versatile stone. Read on if you’re interested in more detail and the couple of reservations I had about the sample as supplied.
I should first clarify that the comparison with the Tassie Tiger stone is not just due to my ‘challenge’ (and I’m not quite the megalomaniac to think Benjamin specifically set out to create a synthetic version of it) – the Tiger is just the preferred stone in my kit and so it is the obvious reference point to which I’ll compare the Fox, and the Fox’s similar performance lends itself to the comparison.
The nitty grit-ty
The Arctic Fox is an aluminium oxide, ceramic bonded synthetic stone, with a ‘glassy’ feel to it – if you roll it around in one hand you’ll hear a distinctive resonant ‘ring’. The very first thing I noticed, though, is that it’s quite thin and, accordingly, super lightweight. I put it on the scales along with some other stones. It’s literally less than half the weight of the Tassie Tiger I grabbed to compare, and while we make no apologies for supplying a deliberately hefty stone as a value-for-money thing, the Fox is certainly going to feel nicer on your hip if you don’t like feeling the weight there.
And yes, it is thin, at 12.43mm on the vernier gauge:
As for the canoeish dimensions, here it is side-by-side with a couple of our other stones:
It’s a very regular-looking stone, although to the fingers it felt to me like it had more bite toward the margins of the flat surface – sliding the thumb across the flat was more ‘grippy’ at the edges, but I’d guess that’s just an artifact of the manufacturing process and any difference would soon settle out with use. The corners look to have been dressed to soften them a little.
The next thing I noticed is that it’s a very thirsty stone. After a quick dunk, our coarse, red, Japanese-made stone soaks up 35mL of water (16% of its own weight), and the Arctic Fox held 20mL (13% of its own weight) – pretty much on par, and yet the Fox is a smaller stone (so the % volume retention would probably be more impressive), and a finer grit stone which looks to be much less porous overall. And it retains the water very well.
There’s nothing to not like so far. I’d be a bit concerned about how well the stone would stand up to being dropped, because it’s so thin. But realistically none of them hold up very well to that treatment: one of our customers happily reported that one of our ceramic whetstones ‘just bounced’ when he dropped it onto concrete, and as I relayed that story at a trade fair, another customer piped up from the audience and said, “mine didn’t.” I’d happily devise some side-by-side strength tests for interest’s sake, but not with just one in hand – it’s far too nice to break.
So far, so good.
On a closer inspection, the softening of the edges didn’t seem to be entirely successful – there were slight chips on the corners. I ignored these – they were small – assuming the stone would ‘settle in’ with use, but the first blade I put it to was a Falci with a fairly fine edge, and I could feel the chips on the edge as I was honing, which troubled me for two reasons: firstly, the blade was hitting the chips, and; secondly, those chips were on the edge of the honing edge… why would that be engaging with the steel? The loading pattern of the grey steel on the stone suggested that it was indeed the edges doing the work, and when I put a straight edge across the stone’s honing edge, sure enough, it was actually slightly concave. Subsequent inspection of the chips revealed either that they were bigger than I thought they’d been, or that they’d grown bigger with that small honing session – I suspect the latter, based on the tactile feedback I’d been getting from the blade and stone.
When I’d first looked at the stone, I’d assumed the edge would be dead flat, which I personally don’t like in a scythe stone, either, because a scythe blade is not dead flat. So even if your whetstone edge is dead flat, when you apply it to a scythe blade, it’s still the edges of the stone that do the work. That bugs me, but I’ve always put that down to personal preference because, after all, when the curve of a blade is so slight in the section where the honing action is occurring, it’s not like we’re talking about a massive angle. And as a whetstone becomes thinner – and this is the thinnest scythe stone I’ve ever used – that effect would be diminished even further. And ultimately, what does it matter if it’s two edges of your stone doing the work, or one point of contact in the middle of your honing edge that’s doing the work? So, up until now, rounding the edges of our whetstones has struck me as a little bit of ‘lore’ that I’ve allowed myself to indulge in: probably unnecessary, but I like to do it because it bugs me otherwise. But this little experience suggests that it can be important, and if it’s justifiable to go to the trouble of softening edges, it’s certainly justifiable to round that entire edge so that the actual edges don’t come into play until the stone has well and truly settled in – otherwise your edges can chip further, which in turn could ‘play rough’ with your blade.
Now, this is hardly a ‘show-stopper’, and knowing Benjamin he’s probably already taken steps to address this in his second batch (but even if he hasn’t, it’s not a show-stopper). Our own ceramics sometimes have chipped edges as well, because I’m now de-glazing them with the same tool I use to grind the Tigers, and it’s not ideal for ceramic (a linishing belt would be better, which I suspect is what Benjamin’s using). But I think we’re getting away with it because I’m no longer just de-glazing the edges, I’m fully rounding them. Our coarse synthetics are as flat as flat, so the edge-of-the-stone engagement will be happening with them as well, but I don’t consider it a real issue with a stone that’s intended to be coarse. (Note to Benjamin – if you can modify your specs to get the edges slightly rounded out of the factory, cost effectively, I’d do it… as you know, a small increase in wholesale cost soon seems like a small price to pay for not having to fluff around with touching up every article yourself, and I think this substance is well and truly good enough that people would pay more for it anyway, so that cost could be passed on).
So, yes, it’s not a showstopper. It stopped me being happy with the stone as it was supplied, but it was only somewhere around 5-10 minutes’ work to lap the Arctic Fox on my coarse synthetic to get the curved edge I prefer:
I decided to compare how it abrades stainless steel, with how other stones perform. This is a very rudimentary form of what I think would be a good standard test for abrasives. The Arctic Fox is apparently rated as 400 grit and this is a case in point for why I don’t place much weight on grit ratings – the Arctic Fox didn’t get the memo that the Arctic Fox is 400 grit; it’s perfectly adequate as a finishing stone – unusually, being synthetic. While synthetic whetstones are certainly available in fine grits, in the realm of scythe ‘canoe’ stones, ‘synthetic’ typically means ‘rip-it-off-coarse’. Falci produce a good ‘medium’ synthetic – but I’d never want to finish a lawn-mowing blade with any of these other synthetic scythe stones. That’s not to say that the Arctic Fox is the only one out there, but it’s certainly the only one I’ve seen.
So, yes, rather than just saying it’s 400 grit and taking a punt on whatever that may mean in terms of actual performance, I thought I’d try to document some actual results. I rubbed each whetstone across a section of marine-grade 316 stainless steel for 100 passes, attempting to apply the same pressure for each. The simple test worked quite well and confirmed my suspicions of what I found while using the Fox – that it did a very similar job to the Tiger. Unfortunately the results were much more visually informative to the naked eye than they are in these photos, but they may be of some use.
The difference between “scratch” and “polish” is of course mainly a matter of magnification – it’s basically all scratch with these stones, it’s just the depth of the scratch that differs, so “scratch” vs “polish” is a subjective naked-eye reference. While the marine grade stainless clearly showed the differences between the coarse and fine stones, it was less useful for showing differences between similarly fine stones, so I decided to try a similar test on softer 304 stainless. The only piece I had to hand was in the form of an attachment ring.
As you can see, the difference between our ceramic and the Fox is ‘chalk and cheese’ on the softer stainless, with a much smoother polish resulting from our finer stone, while even with the softer stainless, I found the Fox and Tiger basically doing an identical job.
While the Fox is the finest synthetic scythe stone I’ve ever used, it also bites hard with pressure applied. The picture here is showing aggregated clumps of 316 stainless which have in turn grooved the loaded face of the stone – this was just an ‘experiment’ to see what would happen, and far exceeded any pressure I’d ever apply in typical honing tasks – but it demonstrates that the Fox is more than capable of ripping off hard steel when it’s asked to do so.
I used the Fox while pruning raspberries, doing some general clumpy grass cleanup, sharpening customers’ blades, and lawn mowing. It performed nicely, and in one case of lawn mowing, brought a previously well-peened, but recently rusty, blade, back to lawn mowing sharpness with no problem at all. This was a favourite Falci 90cm model 100 that had been inadvertently left out in the elements on my back verandah, for months.
The proof is in the pudding, and at the end of this review you can watch me mowing a mossy lawn with a deliberately slow stroke, with a Falci blade sharpened with an Arctic Fox. As any seasoned mower knows, the lush growth of a lawn can look deceptively ‘lovely’ to mow, but the density of the growth – especially when there’s moss in it – can make for frustratingly difficult work. Not so here – it moves with ease.
Where’s the stone?
Yes it does, doesn’t it?
This is one beef I have with synthetic scythe stones – all of the ones I’ve used wear away relatively quickly. Some rather alarmingly so. Further, in wearing, they often seem to wear unevenly, leaving little ridges or other high points in the stone. Here are some examples on my own synthetic stones, and the same issue showing up after more use with the Arctic Fox on the right.
Natural stones aren’t ‘immune’ from such irregular wear, but in my experience it’s the exception, rather than the rule it appears to be with synthetics. The Rozsutec that I’ve used for years, to hone hundreds of blades, is disturbingly regular still.
Which brings me to…
Natural vs. Synthetic
This is a bit of a digression, but I’ve gone on record in the past and said that synthetic materials can always be superior to the natural ones they’re designed to replace, perhaps with some exceptions, with the major constraints being cost/availability (a rock in your paddock will do a much better job of honing a blade than a synthetic stone in a factory 8000 miles away). Considering the products currently on offer, I’m inclined to rethink, or at least qualify that position.
The example of natural fibres is illuminating. Merino wool has been brilliantly marketed in recent years for its qualities as a thermal material. But the fact is that gazillions has been spent on developing synthetic materials to meet specific qualities. Merino is marketed as being ‘unstinky’, and it is – I own synthetic and merino thermals, and I can go camping in the merinos and not find myself offensive after days, while the synthetics are screaming for a wash pretty quickly. But while I also find the merino more comfortable, they’re falling apart while the synthetics purchased around the same time are yet to show any sign of wear. I once overheard a guy who does search and rescue in Tasmania’s wilderness talking to camping shop staff – their voices dropped as they discussed who wears what, and the guy said that he wears synthetics because he’s seen merinos just tear apart when people have tried to take them off their sweaty bodies. I love merino, but strength isn’t one of the qualities this natural fibre offers. To achieve strength, it’d probably need to be blended with something.
With synthetics, you can do that ‘blending’. In theory, synthetic stones similarly should offer all the advantages. You don’t have to worry about comfort or stinkiness with stones, you just need to worry about their abrasive performance. With synthetics, this is ultimately tweakable – particle size, configuration, hardness, bond/substrate hardness… all these factors can be created at will. This is why I say synthetic stones should always be able to be superior to natural stones, which are selected based on similar qualities, but it’s case of having to find the stones that fit the bill.
But what I’m starting to lean toward now is that this synthetic superiority seems to only be a theoretical one. From what I see with the scythe stones currently available, synthetic stones are rarely ‘perfect’ – they wear relatively quickly, they wear unevenly, and their abrasive properties often don’t actually ‘settle’ down until they’ve had some use. So they’re typically much less consistent than natural stones in a number of ways (mind you, our Tassie Tigers are an exception to this in some respects – we ‘prospect’ these, rather than quarry them from a huge, uniform deposit, so they vary markedly in appearance). Given that the industry supposedly has the ability to churn out superior products, the current offerings aren’t terribly impressive in terms of how they wear, for scythe stones at least, and it makes me ask “why?”
I suspect it’s a cost issue. Which brings me to another persistent idea (I wouldn’t want to call it a myth just yet) – that synthetics are cheaper to produce and therefore cost less. Now, I’m not au fait with the details of the economics involved in synthetic stone production, but I do know that we’ve bought natural scythe stones from at least two different wholesalers, at prices that are cheaper than we’ve bought synthetic stones at wholesale. Freight, of course, is a significant factor in the final retail cost, and natural stones are nearly always heavier than their synthetic counterparts. But the density of the natural stone is likely to be related to their (usually) superior longevity. But the opposite has also been true – I’ve seen synthetics offered much cheaper than natural.
I’ve also touched on the environmental factors in producing natural vs. synthetics. Perhaps Benjamin may soon be in a position to furnish some details about the raw materials, by-products, effluents, energy inputs, and so on, involved in the manufacture of synthetics, as compared to the ‘story of waste‘ involved in natural stone production.
So I find myself reconsidering my views on synthetics – at least in the realm of scythe stones. I still acknowledge the theoretical possibility of producing a ‘perfect’ synthetic stone, but the fact that I haven’t seen one yet makes me wonder why, and whether there are genuine constraints working on the theoretical possibility, such that when it comes down to it, producing in natural may ultimately be the most cost-effective way to do it, all things considered.
Natural stone does of course also have that certain charm about it. “The most elegant, classy whetstones I’ve ever seen” was another accolade Ashley Vido gave the Tassie Tiger on receiving several of them recently, and while the Arctic Fox has its own charm (and there is something seductively mesmerising about that resonant, glassy ringing sound it has in the hand), they are very different beasts in appearance and feel. But not in performance.
The Arctic Fox is by far the most impressive synthetic scythe stone I’ve ever used. I would have no hesitation in recommending it as a very versatile stone – and indeed I’ve already introduced Benjamin to a possible new market based on the performance of the stone so far. Will Bladerunners stock it? At this stage, I’m thinking ‘probably not’, but Tony is yet to give me his thoughts. If we don’t, it won’t be due to performance, but rather because it’d be yet another piece of kit we’d be shipping in from elsewhere. That may change, though – we’re already resorting to getting coarse synthetics from Japan.
I think Benjamin has shown exactly the kind of gumption that is really required to ‘make America great again’ (if we accept its past greatness as a benchmark for what ‘great’ means), and if we were in the US we’d definitely stock these. I do expect he will find numerous outlets worldwide, as natural whetstones prove harder to get hold of, and I hope that his success inspires others to investigate local manufacturing options in their neck of the woods.