After thinking about this a bit, I think I understand why this would happen.
The benefits of increasing edge refinement are fundamentally limited by the steel's grain structure. Refining the edge to a finer scale than that doesn't typically help because then sharpening striations are no longer the dominant edge defect.
IIRC you were using VAR-processed White, which would have incredibly fine structure. White is very good to begin with, and VAR further reduces segregation. I can therefore see how using a super-fine stone comprised of "gentle" SiO2 abrasive would make some difference for that specific steel, particularly if you're trying for shavings measured in um.
Nobody was flamed in this thread.
You made a very strong claim that my opinion was "unsupported by facts", and I replied with an equally strong post explaining in detail why that was wrong, except perhaps for very light use. Both posts were contentious, but neither were flames.
Last edited by Patrick Chase; 08-20-2017 at 1:48 PM.
I think that is true. Also it seemed that the wood itself was beginning to be a limiting factor at that point, one of the more experienced competitors (more competition experience) wanted wood with a higher moisture content as he was producing 6 micron shavings with his practice setup.
That steel is hard to abrade but mainly becuase of its literal hardness not abrasive resistance, so the naturals would cut it but I needed to do all of the work with synthetics, so I was effectively taking it up to 12k before refining on the Nakayama.
Last edited by Brian Holcombe; 08-20-2017 at 2:14 PM.
Bumbling forward into the unknown.
Broadly agree Kees, "lesser", how very dare they . Michael, I don't dress my stone, I don't see the point. The India has too much bite when new, it settles in nicely after a bit of use. I can get a sheen or sorts off mine and it cuts more than fast enough. I've never found a record that recommends frequent dressing of oil stones aside form if they start to wear hollow. The concept of dressing oil stones with diamond plates seems pretty odd.
Kees,
Amen on vintage cast steel. My "best" chisels are a set of cast steel Whitherby Warranted socket chisels that I inherited from my father, who I believe, inherited them from my uncle. I also have a set of socket mortise chisels that I got the same way. They all hold an edge very well and yet are fairly quick to hone and to strop. I had them long before I appreciated them. It was a woodworking forum, I think, that tipped me to what I had.
Doug
High quality monocrystalline diamond lapping films can last a very long time, but only if you're very careful. The diamond abrasive particles in those are extremely durable, but can be "stripped" from their resin backing by sharp burrs/nicks. The underlying polyester film is also easy to gouge.
On a related note, what I said earlier about the economics of stones doesn't apply to diamond plates. Those have only a single layer of abrasive, so in terms of abrasive life a stone isn't inherently better than a film. Plates do last longer in reality because nickel electroplating retains diamonds better than resin, but even so I'd take 10 sheets of the 3M 668X film that LV sells over a quality diamond plate (they're about the same price).
Last edited by Patrick Chase; 08-20-2017 at 5:04 PM.
When my stones were purchased films like this were much harder to find than they are today. To me finding some #2000 wet/dry sandpaper seemed like a lucky find.I'd take 10 sheets of the 3M 668X film that LV sells over a quality diamond plate (they're about the same price).
jtk
"A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
- Sir Winston Churchill (1874-1965)
Not really.
Sometimes you need/want diamond for some reason, for example to make shorter work of an extensive flattening job or to handle some really nasty alloys. As I pointed out, there is no realistic "solid stone" option with diamond abrasives, as even the plates are single-abrasive-layer affairs. The point of my reply to Jim was that "scary sharp" becomes competitive with plates in that one specific instance (though pastes are cheaper in the long run, particularly in fine grits).
The earlier post advocating scary sharp referenced SiO2 sandpaper (same abrasive as JNats and Arks), and my previous post was specifically about SiO2, AlOx, and SiC. For those "everyday" abrasives stones of one sort or another are the way to go for medium/fine grits, provided your use is heavy enough to amortize the up-front cost. Just to be complete, I'll note yet again that scary sharp also becomes competitive in very coarse grits with those abrasives.
Last edited by Patrick Chase; 08-20-2017 at 8:01 PM.
For standard tool steel, skipping grits can still give a nice edge and possibly save some time, but for A2 and other modern alloys, the intermediate grits seem to reduce overall time to get to sharp. Transition between grits is pretty quick when sharpening dry on paper, so time to remove the previous grit's scratches would seem to be the place where time might be gained or lost. The minimum time path IMO is through an aggressive ability to remove the dull edge and a process to quickly erase those scratches without multiple transitions, so I see Scary Sharp as trading time for cost of entry...there are def faster systems speed to speed things up. The usual standard observed here is about a minute get a block plane disassembled, tweaked, and back in service with diamond/waterstone and perhaps another minute added to run through the grits on paper/glass, assuming a dedicated sharpening station is available and is set up for use. Not something tested, but we P&P until sharpening is as routine as possible.
Thanks Robert.
I currently have a 6" cheap-o ryobi grinder. The tool rest on it is crap and tiny. I had a bunch of chisels to redo and maintaining a constant bevel, was a serious challenge. Sounds like eventually I'll end up with both a better tool rest and a coarser stone.
Just "adapt" the tool rest..
IMAG0062.jpg
I drilled through the metal rest, and added a wooden platform, that can be tilted as needed, then locked in place. Blue cup is a holder for water to dunk too warm parts into...