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Frederick Skelly
05-30-2016, 3:56 PM
Hi guys. Today, for the first time ever, I pulled shavings with my MF#9 smoother that were 0.001" thick, and full width. My primary bevel is 25* and the secondary is 30*. I use a veritas mark II honing guide. I hone to 6000 on a shapton glass ceramic. Then, I use a leather strop with green compound (with the iron still in the honing guide). In all cases, I only "pull" the iron - I never "push into" the bevel on any grit, including stropping. I've never gotten better than 0.002" shavings. Many times it's 0.003.

The only thing I did different today was to perform the very last step - stopping on leather with veritas green compound - freehand, instead of using the honing guide. Initially, I thought the results to be a fluke, but I was able to repeat it using another iron.

I'm guessing that since freehanding is less precise than using a guide, I may have put a tertiary bevel on the iron. One that is so small I cannot see it. Does that sound right to you? Absolutely nothing else was different than normal, other than freehanding the stropping.

So I'm trying to decide whether the freehanding somehow caused the improvement, and why.

Thanks,
Fred

Edit. One more difference today - I moved the cap iron as close as I could to the edge of the blade. My guess is it's between 1/32 and 1/64". I was working on pine.

Malcolm Schweizer
05-30-2016, 4:41 PM
Perhaps you did a better job of removing the burr by freehand stropping and with the guide you were actually continuing to pull a tiny burr which was flattening out on the first cut.

Bob Glenn
05-30-2016, 4:47 PM
You didn't indicate what you were stropping on. If it was leather, I suspect the blade has been dubbed over slightly, creating the tertiary bevel which you mentioned. I strop my carving knives and chisels, but do not strop my plane irons on leather for fear of dubbing. I think stropping on chipboard or other similar substrate might lessen the dubbing effect.

My only question is, why are pursuing a thinner shaving? Bob

george wilson
05-30-2016, 6:30 PM
I have always sharpened with little circular motions,moving the stone in opposite circles from the blade,if holding the stone in my hand. Of course stropping necessarily MUST be done away from the edge. But,I do change angles on the blade to avoid building up little "mountains" on the microscopic cutting edge. By angles,I do not mean the angle at which I present the blade to the strop. Hope that is clear. Then,I drag the cutting edge through a piece of soft wood a fraction of an inch at a time,to avoid dragging the whole edge through the deposited compound. A few more strops then,and done,if the edge is shaving sharp.

My stones are diamond,black ceramic(Spyderco),white Spyderco,then MDF with LV green compound. If the edge isn't too dull,I leave out the diamond so as to not wear out my tools,especially my favorite pocket knife,the antique one with my ball bearing steel blade. It is a 3 blade whittler,severely plain,with the 2 small blades still in good shape. But,the main blade was too worn down,so I kept it,but replaced it with the 52100 ball bearing steel blade.

Frederick Skelly
05-30-2016, 8:32 PM
Thanks guys! I never felt strongly driven to get shavings better than the 0.002-3 I was getting previously. But I could feel a noticable difference in the way the plane was performing - it just felt smoother and easier to push. And the surface of the wood felt smoother too, though I can't really see why. Might be psychosomatic or something.
Fred

Jim Koepke
05-30-2016, 11:49 PM
My first question is how many strokes did you use stropping?


My only question is, why are pursuing a thinner shaving?

Testing a blade's ability to make a thin shaving is an indicator of its sharpness. I prefer to work with sharp blades. I find it is easier to sharpen a blade when it gets to where it can not take a shaving of less than 0.004" or so. Much duller than that and it takes more time by hand or it has to be set up on a powered sharpening system.

I tend to sharpen bench and block plane blades without a camber. Some may sneak in unintentionally. With a very fine shaving on a smoother there are usually no tracks. Any that do occur are easy to remedy.

The thinner the shaving the less likely there will be tear out.

With a very thin shaving it is easier to set the lateral adjustment.

A thin shaving requires a well sharpened blade. I may be wrong, but the sharper the blade for any given bevel, the longer it will be before it is in need of another sharpening.

My procedure is to sharpen a plane blade and then set the lateral with as thin a shaving as possible. Then the plane is set for a realistic shaving for the work at hand and it is off to the races.

jtk

Patrick Chase
05-31-2016, 12:54 AM
Thanks guys! I never felt strongly driven to get shavings better than the 0.002-3 I was getting previously. But I could feel a noticable difference in the way the plane was performing - it just felt smoother and easier to push. And the surface of the wood felt smoother too, though I can't really see why. Might be psychosomatic or something.
Fred

Err, "better" is a dangerous word in the context of shaving thickness, unless you're entering Japanese planing competitions or something like that. Size doesn't matter in this context.

IMO smoothing is incredibly tedious when done a mil at a time, and indeed the productivity grain from being able to take thicker shavings without tearount is the key advantage of a close-set cap iron. If your surface quality is also better then that's an infinitely more meaningful benefit of course.

Kees Heiden
05-31-2016, 3:06 AM
To answer one question: You can move the edge back and forth on the stone. You don't need to lift it on the back stroke. Going back and forth or in circles, or figure eights is a lot quicker. Of course, not on the strop, or you'll rip up the leather.

Frederick Skelly
05-31-2016, 6:57 AM
My first question is how many strokes did you use stropping?

jtk

Hi Jim. I did 10 strokes by hand, like I usually do with the honing guide.
Fred

Frederick Skelly
05-31-2016, 6:59 AM
To answer one question: You can move the edge back and forth on the stone. You don't need to lift it on the back stroke. Going back and forth or in circles, or figure eights is a lot quicker. Of course, not on the strop, or you'll rip up the leather.

Thanks Kees!

Jim Koepke
05-31-2016, 9:18 AM
Err, "better" is a dangerous word in the context of shaving thickness, unless you're entering Japanese planing competitions or something like that. Size doesn't matter in this context.

A sharper blade also helps with the thicker shavings. When the same sharpness is used on a bigger plane the smoothing goes rather quick even when taking very light shavings.

Often there are times I do not need to smooth after using a #6, 7 or 8.

jtk

lowell holmes
05-31-2016, 10:05 AM
I "strop" on mdf charged with green honing compound. Try it, it works.

Luke Dupont
05-31-2016, 10:31 AM
I've been sharpening with convex bevels, using Paul Seller's method. I start off at 25 degrees, as you do, and probably end up around 30-35 degrees at the very edge.

I'm not at all afraid of "dubbing the edge," usually. The one exception is on planes with low-bedded irons, such as my Japanese plane that is bedded at 41 degrees. In that case, 35 degrees would be too steep an angle, so I'm careful to keep it closer to 30.

When you sharpen by hand, or strop, you will produce a slight convex on the blade regardless of what you do. I go ahead and sharpen freehand, working the entire bevel, and not worrying about the convexity, starting on a fairly coarse stone. I finish on a leather strop, and while I go fairly vigorously, I do not find it dubs my edge significantly. It *does* add to the convex shape of the blade, but if you keep the plane iron/chisel at 25 degrees or so, it won't typically produce an edge steeper than about 30-ish degrees. I usually flip my chisel/plane iron over, so it's riding on the bevel, and check what angle it starts cutting at to confirm this.

I find this method gives me very good results, but I haven't actually measured my shavings. Just mentioning it in case you want to try it with a spare iron or something. Not worrying about exact angles and primary/secondary bevels really freed up sharpening for me, and made it much more enjoyable, as it's now just a process of intuition and experience as opposed to exacting precision.

Andrey Kharitonkin
05-31-2016, 10:39 AM
To answer one question: You can move the edge back and forth on the stone. You don't need to lift it on the back stroke. Going back and forth or in circles, or figure eights is a lot quicker. Of course, not on the strop, or you'll rip up the leather.

The second question that can be asked is - what stroke should be emphasized.
The third question is where do you apply pressure while using honing guide.
And forth is how you finish honing to get a micro bevel.

I learned to do the same but without stropping (about to try that soon) and I use Cerax 1000/6000 combination water stone. I can plane such a shaving that becomes sticky to the surface of the wood and nearly transparent.

My answers to those questions currently are:
2. On push stroke more pressure - sharp edge holds longer.
3. Fingers push on near the edge of the blade, never pressure on the guide roller - helps to avoid skewing of the edge and allows to learn cambering with veritas camber roller.
4. Increase angle as progress through stone grits - ensures that scratches and defects left by coarse grits are removed near the edge where it matters, see manual of veritas honing guide about that knob on the right of the roller.

But it also could be that your stropping just rolled edge over and made it dull. Maybe try the same but without stropping?

Patrick Chase
05-31-2016, 2:31 PM
To answer one question: You can move the edge back and forth on the stone. You don't need to lift it on the back stroke. Going back and forth or in circles, or figure eights is a lot quicker. Of course, not on the strop, or you'll rip up the leather.

This depends somewhat on the stone and on the user's technique. On a hard/translucent Ark or a harder waterstone like Shaptons or Choseras, yes, that's exactly right.

I saw somebody put one h*ll of a divot in a #10000 Ohishi (a fairly soft resinoid stone) that way at the L-N showroom, though. I can think of several other high-grit stones that are on the soft side and would likely be similarly vulnerable to forward strokes with marginal technique.

lowell holmes
05-31-2016, 2:47 PM
https://www.toolsforworkingwood.com/store/item/NO-SVIDEO-OIL

I use the sharpening technique shown in the referenced video
I sharpen from side to side instead of forward and back. I hone on a piece of mdf charged with green compound

My shavings are translucent and the edges are extremely sharp.

Kees Heiden
05-31-2016, 2:48 PM
I've always gone back and forth when I still used my Naniwa superstones. Those were soft too. And yes, sometimes I hooked an iron into the soft surface. Shit happens. After a while and several flattenings the gouge was usually gone, just to be replaced with a new one. But I am not the kind of guy who can bring up the patience to pull a chisels backwards, lift it up, return to the start, find the right angle again, and do another slow and deliberate pull stroke. I am more a "swoosh, swoosh, got a sharp edge" kind of guy.

Mike Cherry
05-31-2016, 5:40 PM
I've been sharpening with convex bevels, using Paul Seller's method. I start off at 25 degrees, as you do, and probably end up around 30-35 degrees at the very edge.

I'm not at all afraid of "dubbing the edge," usually. The one exception is on planes with low-bedded irons, such as my Japanese plane that is bedded at 41 degrees. In that case, 35 degrees would be too steep an angle, so I'm careful to keep it closer to 30.

When you sharpen by hand, or strop, you will produce a slight convex on the blade regardless of what you do. I go ahead and sharpen freehand, working the entire bevel, and not worrying about the convexity, starting on a fairly coarse stone. I finish on a leather strop, and while I go fairly vigorously, I do not find it dubs my edge significantly. It *does* add to the convex shape of the blade, but if you keep the plane iron/chisel at 25 degrees or so, it won't typically produce an edge steeper than about 30-ish degrees. I usually flip my chisel/plane iron over, so it's riding on the bevel, and check what angle it starts cutting at to confirm this.

I find this method gives me very good results, but I haven't actually measured my shavings. Just mentioning it in case you want to try it with a spare iron or something. Not worrying about exact angles and primary/secondary bevels really freed up sharpening for me, and made it much more enjoyable, as it's now just a process of intuition and experience as opposed to exacting precision.

This post sums my sharpening up almost exactly. I have a low angle Jack that has a specific bevel angle and it's the only reason I have a eclipse style jig still. I do use a plain strop but I never had luck doing that vigorous stropping thing Sellers does. When Luke says this freed things up for his sharpening, I can't agree more. It is this method of sharpening that has made me feel comfortable and confident with sharpening carving gouges, knives, double beveled letter carving chisels, scrub blades....you get the idea. I'm not trying to push freehand sharpening on anyone, but man it does open up a whole other world in terms of tools you can play...er work with lol

Derek Cohen
05-31-2016, 7:39 PM
If you wish to ensure that the bevel does not creep beyond a specific angle when freehand sharpening, then hone directly on a hollow grind. The hollow both reduces the amount of steel to hone, and acts as a guide for a specific angle.

Regards from Perth

Derek

Patrick Chase
05-31-2016, 8:28 PM
If you wish to ensure that the bevel does not creep beyond a specific angle when freehand sharpening, then hone directly on a hollow grind. The hollow both reduces the amount of steel to hone, and acts as a guide for a specific angle.

Regards from Perth

Derek

If I weren't too "retentive" to freehand this is exactly what I would do :-).