How "unflat" is problematic with the diamond stones?
- This topic has 12 replies, 7 voices, and was last updated 04/15/2018 at 9:34 pm by
.
-
In use I doubt you will find it to be an issue until you get to the higher grit stones.
2 users thanked author for this post.
11/1000 of an inch is a very small difference. If we were dealing with a CMC machine I would be concerned. We are hand manipulating these stones up and down the bevel trying to maintain a flat consistent contact while sliding the stones up and down the guide rods through their angular motion. The stones move around under our guidance no matter how perfect I would like to believe someone’s technique may be surely more than 11/1000 of an inch.
IMO, I say it’s a non issue. It’s much less of an error than the operator will introduce through normal use. The error is smaller than can be measured with the Dual Axis DXL360S Angle Cube, the most precise one I believe any of us uses.
Marc
(MarcH's Rack-Its)2 users thanked author for this post.
.011″ is easily visible with the naked eye. If I was doing a fine woodworking project and I ended up with .011″ gaps in my joinery I’d throw that part out and re-do it. That’s too big a misfit for my taste, but others may be fine with it. But if I’m just slapping together 2×4’s to build a crude shelf, that’s a different story, and a .011″ error isn’t important.
For the WE sharpening application, I just don’t know where a .011″ stone flatness error lands on the care/don’t care spectrum. I guess what you and RazorEdge are saying is that it’s not going to have any visual or sharpness impact on the blade’s edge.
Marc, if you wouldn’t mind, could you elaborate on “It’s much less of an error than the operator will introduce through normal use”
This system all seems pretty tight to me and I’m not entirely clear what things I would do while using the WE that would introduce far more error than this. It seems like something that would be good to keep in mind as I get started with using it.
Thanks.
1 user thanked author for this post.
Marc, if you wouldn’t mind, could you elaborate on “It’s much less of an error than the operator will introduce through normal use” This system all seems pretty tight to me and I’m not entirely clear what things I would do while using the WE that would introduce far more error than this. It seems like something that would be good to keep in mind as I get started with using it. Thanks.
Graphite, as you move the stones they rotate around a metal rod across a angular shaped piece of metal, (the bevel) along an axis that may change as you slide along it depending on the shape of the knife, (the blade’s edge), the area of contact, (the contact patch), both on the stone and on the bevel, is constantly changing as the stone moves across the bevel. These stones are being held lightly by your finger tips, on two different hands, so as not to exert extreme pressure but to allow the stone’s abrasiveness to do the work. The pressure of your fingers are not necessarily exerted evenly all across the stone’s length and not necessarily evenly across both of the stones, as the stones moves further away from you or closer to you as they are moved across the knife to sharpen it, and not necessarily the same from moment to moment, or from right side to left side. It is being done free-hand, although guided. Also there is an inherent amount of tolerance between the guide rods and the internal walls of the bore holes that may or may not be constant as the stone moves along the bevel and the guide rods. All of these factors introduce an element of error, stationary and in motion, that I believe far exceeds the error of the unevenness of the stone by 0.011″ will cause to your sharpening. As you move the stone across the bevel our intent is to maintain constant contact between the stones and the bevels. I believe even with that small error you will still maintain good enough contact if you develop and apply good sharpening technique.
I believe you are examining this system with a degree of scrutiny and skepticism on a level I have not scene before especially by someone who states he has yet to even use the sharpener. After you learn to use it I hope you will enjoy it as well as I have.
Marc
(MarcH's Rack-Its)1 user thanked author for this post.
Thanks Marc. It’s taking some restraint not to jump right in and begin sharpening, but I want to get the magnified photos of the new stones first, and I only have one chance to do that (and also learning how to use the microscope takes a bit of time). Hopefully I’ll begin sharpening later this weekend.
I used an Edge Pro previously, and, long story short, I just couldn’t get repeatable results with that. But I don’t want what are perhaps bad habits I developed with the EP to carry over to the WE. And since the edge pro has horizontally-oriented stones while the WE is vertical, it seems like gravity provides some aid on the edge pro in keeping the stone face on the bevel (or at least, more so than on the WE). In some ways it might be easier to begin using the WE if I had not had the prior experience with the EP due to the difference in stone orientation.
You may not agree, but for me I think my odds of getting good results with the WE will be increased by trying to understand as much about the mechanics of the WE system pieces as I can, before I start. So that’s what I’m trying to do.
1 user thanked author for this post.
In use I doubt you will find it to be an issue until you get to the higher grit stones.
I completely agree with Josh. Even if the stones are not completely flat, they will still remove metal from the edge all over. Only the angle may vary slightly, but I think is negligible.
I believe you are examining this system with a degree of scrutiny and skepticism on a level I have not scene before especially by someone who states he has yet to even use the sharpener. After you learn to use it I hope you will enjoy it as well as I have.
+1
Molecule Polishing: my blog about sharpening with the Wicked Edge
1 user thanked author for this post.
You may not agree, but for me I think my odds of getting good results with the WE will be increased by trying to understand as much about the mechanics of the WE system pieces as I can, before I start. So that’s what I’m trying to do.
This is all well and good as long as you can remain objective. My fear is this data your attempting to capture in this once in a lifetime opportunity may guide your opinion. I think you’ll anticipate results based on your study and data and be disappointed when the results differ. Maybe you’ll determine it’s problematic because it didn’t meet those preconceived expectations. You also have to remember you have a hand in this. It’s not just the Wicked Edge doing everything alone. It’s just a clamping system. You’re the operator; the motion.
Marc
(MarcH's Rack-Its)1 user thanked author for this post.
I was checking my just-received diamond stones (100/200, 400/600, 800/1000 pairs) for flatness using a precision-ground bar stock and some feeler gauges in .001″ increments. All my stones except one are pretty flat (mostly within .002″ or less). But one of the 600 grit stones is out of flat by .011″ on one end and .004″ on the other. Should I send that one back to get a new one that is hopefully flatter? That would seem to be a bit much.
I’m not sure I understand how you are measuring flatness here, but for what it’s worth, assuming that the edge is five inches above the pivot point and if your angle is set at 20 degrees, an error of 0.011″ would translate into about a tenth of a degree. I took a four-hour crash course in trig when I was at ET school at NTC Treasure Island and it’s served me well for over fifty years. (Suzie Can’t Tell, Oscar/Had A/Hunk Of/Ass). The height of the edge above the pivot is the Adjacent side of the right triangle and the distance from the centerline of the knife to the point where the stone’s face would intersect the horizontal axis would be the Opposite side. Add (or subtract) 0.011″ to the Opposite side and the angle changes (coincidentally) by 0.11 degrees.
This is what happens when the stone thickness changes, requiring the use of the VSTA adapters or use of an AngleCube. In this case, we’re talking about variations within a given stroke, so the result is that this stone will produce a bevel that is slightly out of “flat.” After a nominal number of strokes, I don’t think you’ll be able to see the error, even with a microscope.
2 users thanked author for this post.
tcmeyer, re: “In this case, we’re talking about variations within a given stroke, so the result is that this stone will produce a bevel that is slightly out of “flat.” After a nominal number of strokes, I don’t think you’ll be able to see the error, even with a microscope.”
Thanks, that’s exactly what I was asking about.
The way I measured the out-of-flatness was I took the bar stock (precision straight edge, really) and laid it down the middle of the stone lengthwise, standing it on its side (the bar stock is 9/32″ thick so it stands up on the stone on its own, and is longer than the length of the stone), and then I place a small LED light behind it and look for light leaking through where the stone meets the bar. In those places I inserted a feeler gauge (.001″ increments beginning at .001) until they no longer slide into the gap. The feeler gauge one less than that point is what I am taking to be the flatness error. It took maybe 5-10 minutes to do all six stones (12 faces)
2 users thanked author for this post.
I’m reading this as a cook and thinking “damn, that tomato is going to be AFUp…and I’m sure to lose my job” 😉… lol, I guess such precision is relative to one’s interests relative to the technology of sharpening. Sorry Graphite, not trying to make fun of your observations or concern here theyre simply very different from my own perspectives.
If it was me I would send the stone back and ask for another one I believe the problem probably lies in the paddle its self seeing how its plastic or the glue funny how most are dead set on using the digital angle gauge etc. and then when the paddle is out of whack its “ok” Clearly the item is defective and should be replace
LV Sorry to have drawn you in on this one. I suspect given the age of the thread (last December) the issue has been resolved by WE (as is typical of their customer service business model) and/or at least addressed by the participants to Graphite’s satisfaction. My apologies to all concerned for having inadvertently raised the dead! 😉
1 user thanked author for this post.
- You must be logged in to reply to this topic.