“Smith’s Hard” (relatively fine soft arkansas) Before and After 2.5 Micron Diamond Charge

Same idea as the prior posts examining whether 1 micron diamonds improve the sharpening (for the user, not the tool) and resulting edge on a black arkansas stone. In that case, I think 1 micron diamonds do improve the outcome, and though I didn’t go up the ladder in more complex steels, but the diamonds probably make the oilstones more capable of dealing with those (where complex means microstructure full of carbides that are harder than the oilstone). It does seem to be the case, though, that on wood or well machined cast iron, the resulting edge with 1 micron diamonds is still better, so maybe it boils down to whether or not you like the feel of the stone better than either of those. I do.

But, what about more coarse stones? First, if you need to go very coarse with oilstones, or even to something similar to a 1k water or broken in diamond stone, a well-used india stone is a good idea. A stone like a soft arkansas or washita will easily follow and set up an edge that is short work on the finish step.

So, that leaves me to define more coarse as something like a washita or a “smith’s hard” which looks kind of like and feels kind of like a washita, but doesn’t seem to have the same cutting power. I have one of these that came in a box for $10 on ebay. If they climb too much past that in price, they’re forgettable. I found the same with 2.5 micron diamonds on cast iron -the edge isn’t that great for the fineness and I can’t think of a reason to use them unless they’re dropped on wood until the fun of that wears off (autosol is easier to use in that situation).

So, figuring I had two forgettable sharpening media, I put the 2.5 micron diamonds on the smiths hard and charged right in. Which negates the ability to take “before”. Luckily, I have some on file from prior tests – so this isn’t a great comparison in terms of same item, same time, but it’ll do.

Here’s the result of the “Smith’s Hard” on a plain carbon steel iron that’s not terribly hard.

You may start to notice a theme – the visual differences between finishing stones aren’t that great. In this case, the edge is very even, and the result is better than one would expect. I think this is helped (this positive result) by the fact that the stone is a bit slow. If you have harder steel, the result is finer yet, but it’s also the case that this middle stone needs help before it on harder steel. As in, if you have much work to do with the stone, the slow speed gets annoying and it goes back in a drawer, replaced by a washita which does the same thing but cuts faster.

Following that with a perhaps-too-generous charge yeseterday while using a paring chisel (for real work, no less – paring the back side of a guitar neck heel), this is what the microscope reveals.

Once again, we have two unlike pictures and it’s difficult to look at the two and know which edge is better. Well, just from using the tools, the edge shown in the second picture is a lot sharper. Paring hard maple to fit a neck heel to a guitar body was extremely pleasant (paring hard maple in some thickness beyond that, not always so pleasant).

Is it an improvement? Definitely. Is it better than anything else? I don’t know – what stands out to me for ease is still autosol on wood. It’s difficult to beat in terms of creating a sharp and durable edge.

From sharpening, the diamonds do create sort of a rolling slurry/sludge on the stone even though they’re just dry diamonds. I don’t know if this is all metal swarf mixed with WD-40 or if it’s also stone particles. But it’s fairly obvious from the picture, the cutting mechanism isn’t the same – the matte type finish is more indicative of some rolling/moving particles vs. abrasive staying in place. If the sludge gets to be a bit much, then a drop or two of WD40 allows it to move again. It’s not, by any means, fast compared to diamonds in cast but the edge is surprisingly excellent from two bits of sharpening material that don’t seem that great on their own.

Since I have them on hand – here are two pictures of the stone box and the stone. Note that it looks relatively fine (it is, and so are some other soft arkansas stones). This stone is not, however, similar to a Norton or Dan’s Black or Translucent arkansas stone. Smiths is a name that’s still printed on stones. I can’t comment on the stones beyond saying that they appear to be a little bit less fine now and I have no clue whether the company has been bought and sold or doesn’t exist and it’s just the brand name.

Smith’s Hard – Not an 1800s stone, but not a new stone, either. Finishes about as finely as a good washita stone, but is only half as fast or less.