Ruler trick example

[Patrick Chase]

This is a tangent from Stewie's "stone flattening" thread, particularly the assertion that ruler-tricking is used as a substitute for flattening the back of an iron. Here's an example of ruler-tricking done as Charlesworth recommends (a quickie snap of the iron from my L-N 8). Note the mirror-finished strip immediately behind the edge:

347908

The back of the iron is dead flat, though not mirror-polished. I worked it to 3 um, or about #4000. The edge was then "ruler-tricked" on 0.5 um diamond paste (#20000-30000) using a 1/4 mm strip of shim stock set about 60 mm back from the edge. The result is a 1/4-deg back bevel, extending a few tenths of an mm back from the edge.

It's probably worth noting that the edge is only recessed from the back by a couple microns at most (~0.5*sin(1/4) millimeters), so the back has to be very flat for this variation of the ruler trick to work. Higher back-bevel angles (from thicker shims or shims positioned closer to the edge) and/or bevels extending further back from the edge will be more tolerant of imprecise flattening.

[Pat Barry]

Nice job! Thanks for the snapshot

[Glen Canaday]

Now I understand what this trick thing is.

My only question is, why?

[Jim Koepke]

The back of the iron is dead flat

To my thinking there is not a good reason to bother with 'ruler tricking' if the back is dead flat.

My blades are usually taken to the stones before enough of a wear bevel builds up to not be removed by honing the bevel.

Of course my methods are clearly different, as are those of others. Like so many my efforts are used on ways found to work for me in my environment.

Little time is spent flattening stones, making secondary bevels, ruler tricks or even hollow grinding. Hollow grinding works for me, but I do not have an electric grinder. A flat bevel is no big deal to sharpen.

Out of a desire to get into the shop before my doctors have cleared me for woodworking some time today was spent working on a pair of type 6 #4s. I am swapping some parts around that got switched between the two. (One has a new paint job the other doesn't. The frogs got mixed when they were reassembled.)

The first one was put back together with as many of the original type 6 parts that I have. The blade was inspected and though it was fairly sharp it wasn't as sharp as can be. A few strokes on a 4000 stone and the back was cleaned up of any residue. The bevel was also touched up on the 4000 stone. Then a bit more time was spent on an 8000 stone to get as close to a mirror on the back as could be obtained and the bevel was worked until it could shave hair. Then some swiping on the strop.

After all of this the plane was reassembled and the blade was adjusted to take as fine a shaving as it could without the wood turning to dust. With a little bit of careful adjustment my best shaving was 0.0005".

Now that isn't something that is going to do much good in most situations, but is there really any reason to change my approach?

Maybe a better, more to the point question would be; what advantage would be gained by using the ruler trick?

I came in for a spot of lunch. One more plane to put back together and get working. I'll try to remember to bring the camera out to the shop.

jtk

[Pat Barry]

To my thinking there is not a good reason to bother with 'ruler tricking' if the back is dead flat..

A few strokes on a 4000 stone and the back was cleaned up of any residue. The bevel was also touched up on the 4000 stone. Then a bit more time was spent on an 8000 stone to get as close to a mirror on the back as could be obtained and the bevel was worked until it could shave hair.
The entire reason for the ruler trick, er shim stock trick, is to save you from all the work needed to get a mirror / dead flat back. Sometimes its worth it to try a different approach.

[Jim Koepke]

The entire reason for the ruler trick, er shim stock trick, is to save you from all the work needed to get a mirror / dead flat back. Sometimes its worth it to try a different approach.

I have tried the ruler trick.

Once a back is flat, unless one wears it to the point of not being able to cut, it shouldn't need flattening again.

Now days, once a blade's back is flat, the most their backs get to the stones is to remove any pitch that builds up where the chip breaker meets the blade or to remove a burr.

jtk

[Steve Elliott]

Patrick's method is similar to mine for bench plane blades. The advantage of flattening the back is that it allows the microbevel to remain very narrow. This means only a tiny amount of steel needs to be removed each time the blade is honed.

Jim's method of using a strop for final honing has an effect similar to a narrow, very shallow microbevel. Because the strop is somewhat resilient it takes a little more off the edges.

In my experience it is much more difficult to get a large surface like the back of a blade to a highly polished state. Using either a microbevel or a strop puts the sharpness right where it is needed--at the cutting edge.

[Patrick Chase]

The entire reason for the ruler trick, er shim stock trick, is to save you from all the work needed to get a mirror / dead flat back. Sometimes its worth it to try a different approach.

That's right - In the blade in the photo the back-bevelled part is fully polished (i.e. all striations from preceding, more coarse grits removed) to the equivalent of #20000-30000. Doing that without the help of the shim is a pain in the a**, because you end up spending tons of effort polishing metal that will never see wood. I've done it, and it's a massive waste of time.

[Patrick Chase]

I have tried the ruler trick.

Once a back is flat, unless one wears it to the point of not being able to cut, it shouldn't need flattening again.

No, the back has to be flat AND POLISHED. Getting it flat is the easy part. Getting it polished to the point of removing *all* scratches/striations is much more time-consuming unless you use a very slight back-bevel to "focus" your polishing efforts on the portion of the back adjacent to the edge. As several people including David Charlesworth himself have said several times, the ruler trick is a polishing aid, not an alternative to or replacement for flattening.

Also, if you plane abrasive wood then it can screw up your polish immediately behind the edge long before it degrades to the point of "not being able to cut". This is particularly true of BU planes in my experience.

[Patrick Chase]

Patrick's method is similar to mine for bench plane blades.

Indeed. I'd previously used one of your pictures (http://planetuning.infillplane.com/index.html) to illustrate this. For that matter I also use diamond paste on cast iron (or mild steel), though I haven't taken my "honing guidance" to quite your level of refinement :-).

You bring up a good implied point: This is only valid for tools that cut with a fair amount of clearance. It doesn't make sense for chisels (zero clearance when paring) or for low-angle spokeshaves (very low clearance) for example.

[lowell holmes]

Now I understand what this trick thing is.

My only question is, why?

Because you can hone an edge on the bevel and the ruler trick puts a micro-bevel on the back. It is down, dirty and very fast.
I find it to be effective, so I use it. I do hone the back of my irons on the first sharpening, but not subsequent sharpening's.
I use it. I would rather spend my time working the wood.

[Patrick Chase]

I should have remembered to say...



Out of a desire to get into the shop before my doctors have cleared me for woodworking some time today was spent working on a pair of type 6 #4s. I am swapping some parts around that got switched between the two. (One has a new paint job the other doesn't. The frogs got mixed when they were reassembled.)

The first one was put back together with as many of the original type 6 parts that I have. The blade was inspected and though it was fairly sharp it wasn't as sharp as can be. A few strokes on a 4000 stone and the back was cleaned up of any residue. The bevel was also touched up on the 4000 stone. Then a bit more time was spent on an 8000 stone to get as close to a mirror on the back as could be obtained and the bevel was worked until it could shave hair. Then some swiping on the strop.

After all of this the plane was reassembled and the blade was adjusted to take as fine a shaving as it could without the wood turning to dust. With a little bit of careful adjustment my best shaving was 0.0005".

Welcome back to the land of the (woodworking) living! Glad to hear you've been able to get some work in.



Now that isn't something that is going to do much good in most situations, but is there really any reason to change my approach?

Heavens no. I was trying to clear up some misconceptions (in other threads) about what the ruler trick is and why it's used, not arguing that everybody should do it.



Maybe a better, more to the point question would be; what advantage would be gained by using the ruler trick?

Faster polishing, particularly if you're going to very fine grits and trying to remove all striations.

[Stewie Simpson]

To my thinking there is not a good reason to bother with 'ruler tricking' if the back is dead flat.

Thanks Jim; that's a very pertinent question.


Patrick; excellent to see your using a camera for a change.


Stewie;

[Patrick Chase]

Thanks Jim; that's a very pertinent question.

No, it's completely irrelevant and grounded in confusion about what the bevel trick is trying to accomplish (as was your similar comment in the other thread).

The bevel trick is about polishing, not flatness.



Patrick; excellent to see your using a camera for a change.

Yeah, as with the needle file thing your nonsense finally motivated me to break it out.

[Stewie Simpson]

My personal take on micro back bevels; is that it reinforces laze of technique in preparing the back of your plane iron. Its not as though we are discussing the full back of the iron. An area within a range of 1/2 to 1 inch is ideal target to aim for. I made mention of the fact that it encourages laze of technique for good reason, as what generally occurs is that practice soon migrates to being used on the backs of chisels, and that is a well entrenched no no.

Stewie;

[Devon Curtis]

To accomplish something similar, but with a less drastic back bevel, I use a strip of UHMW tape affixed across the back of the blade. I find this approach particularly useful when rehabbing old blades that may be especially out of flat. It establishes a flat strip at the edge that is easily transitioned into the rest of the back with further sharpening. I find the UHMW tape usually holds up quite well over a single sharpening session, only tearing or fraying if used with very coarse stones (<500 grit, typically). I've even left the tape on after sharpening and resetting the blade, and used it for a second session.

I should mention that I got the idea to try this after reading Chris Hall recommend the use of UHMW tape when dealing with sori afflicted kanna blades. Thanks, Chris.

[Patrick Chase]

My personal take on micro back bevels; is that it reinforces laze of technique in preparing the back of your plane iron. Its not as though we are discussing the full back of the iron. An area within a range of 1/2 to 1 inch is ideal target to aim for. I made mention of the fact that it encourages laze of technique for good reason, as what generally occurs is that practice soon migrates to being used on the backs of chisels, as that is a well entrenched no no.

Stewie;

OK, so let's see your pictures showing that you've achieved a complete polish (no striations larger than the finest grit you use, presumably 0.5 microns) over 1/2" to 1" of your iron.

As noted above the fact that I was able to put a consistent 1/4-deg back bevel <0.5 mm wide on the edge indicates that the back was already flat to within microns
. If the blade weren't that flat to begin with then I would have had to use a higher back-bevel angle or make the bevel much thicker. I don't think that any sane person would call that "laze".


More precisely, the iron and the steel plate that I used for back-beveling had to be coplanar to within a couple um. I'm sure they're both flat to within about 1/5000" (if your eyesight is any good you can detect that with an accurate straightedge and strong lighting) but I don't have an interferometry setup here at home so I can't make a statement stronger than that.

[Jim Koepke]

Welcome back to the land of the (woodworking) living! Glad to hear you've been able to get some work in.

Thanks Patrick I have been out to the shop a couple times just to sit and enjoy my 'man cave' environment.


Faster polishing, particularly if you're going to very fine grits and trying to remove all striations.

My finest stone is an 8000 Norton. My chart puts that at 1.2µ. I do not bother to put in all the work it takes to remove all the striations produced by the coarser stones. The 8000 seems to leave a few of its own, at least some new finer lines are visible after it is used.

347916

This is after stropping on leather charged with green compound. There are still striations all the way to the edge.

A little more time was taken with this blade than the earlier one today. The results may be indicative of the striations not being the big problem one might imagine.

347918

From my understanding of reading a micrometer the shaving is > 0.0002" yet < 0.0003". I would still need to get about half of that to think about competing in a Japanese woodworking planing challenge.

Now most of us likely agree there isn't a need to make shavings this thin during the normal coarse of our woodworking. Though on a day with a bit of a breeze it is kind of fascinating to make shavings and watch them float ever so slowly away.

So again only speaking for myself, it seems two or three stones and a piece of charged leather has me 'polishing' my blades fast enough without having a ruler or shim to clean nor a surface plate or other equipment to set up and maintain.

Just to reiterate, My stones have not been flattened for a while. Though I did change the water today in the plastic box where they soak. My sharpening is done free hand. No time was used to set up a blade holder since the only one in my shop is a jerry rigged affair, only used when a blade needs a lot of work on coarse media. The bevel is as flat as my hands can maintain. If there is any camber to the blade it is not intentional and likely less than 0.001" from center to the edges.

Now if someone can show me the ruler trick is the only way to get shavings in the one ten thousandths or less range, then I would be interested and if it ever comes to the point of my needing to take such a thin shaving, then I would likely give it another try.

jtk

[Shannon Cuffe]

I have always been of the opinion that the backs of plane irons need to be dead flat so that you can remove the burr easily and also so it is easy to make the chipbreaker mate well with the back of the iron. But recently I started using a new plane with a new iron which looks like it has been fairly closely flattened using one of those rotary worksharp things or similar. It definitely is not dead flat, and certainly not polished. I haven't been bothered to flatten and polish the back of it and I have taken to sharpening the bevel as per my normal routine and simply stropping the burr off using a kangaroo tail leather strop with CrOx crayon. It works well, extremely well, so there is zero chance of me bothering about flattening the back of that iron because I can't gain anything worthwhile above "extremely well".

On a side note. when I purchase an old junker plane from fleabay and find that the iron has a massive back bevel on it. I just throw the iron straight in the bin. The ruler trick works, but it seems that it is commonly misunderstood. I don't do the ruler trick myself because in my mind it is just an unnecessary complication, which is much the same reason why I use my hands as push sticks more so than using an actual push stick.

[Jim Koepke]

I should mention that I got the idea to try this after reading Chris Hall recommend the use of UHMW tape when dealing with sori afflicted kanna blades. Thanks, Chris.

Howdy Devon and welcome even though you have been hanging in the shadows for a few years.

Not sure if I would know if any of my blades were sori afflicted. Can it happen to blades in metallic planes?

jtk

[Patrick Chase]

To accomplish something similar, but with a less drastic back bevel, I use a strip of UHMW tape affixed across the back of the blade. I find this approach particularly useful when rehabbing old blades that may be especially out of flat. It establishes a flat strip at the edge that is easily transitioned into the rest of the back with further sharpening. I find the UHMW tape usually holds up quite well over a single sharpening session, only tearing or fraying if used with very coarse stones (<500 grit, typically). I've even left the tape on after sharpening and resetting the blade, and used it for a second session.

I should mention that I got the idea to try this after reading Chris Hall recommend the use of UHMW tape when dealing with sori afflicted kanna blades. Thanks, Chris.

Yep, I've done that as well, though I think you may be overestimating the degree of bevel I applied when you say "drastic". It was 1/4 deg (10 mil shim stock set 60 mm back from the edge).

How thick is your UMHW tape and how far back from the edge?

More broadly I'm personally not a fan of using back-beveling as a substitute for flattening, because you then lose control of the geometry of the bevel region leading to trouble with cap-iron mating. I think it works best as a polishing aid *after* flattening.

[Stewie Simpson]

No, it's completely irrelevant and grounded in confusion about what the bevel trick is trying to accomplish (as was your similar comment in the other thread).

The bevel trick is about polishing, not flatness.



Yeah, as with the needle file thing your nonsense finally motivated me to break it out.


Patrick; this notion that you are just polishing the back of the iron to produce a micro back bevel is misleading. If its practice is designed to create a secondary plane, then there is a requirement to remove, not polish the metal.

[Patrick Chase]

My finest stone is an 8000 Norton. My chart puts that at 1.2µ.

The latest JIS standard is indeed ~1.2 u at #8000, but the Norton 8K is non-JIS-compliant at 3 um (http://www.leevalley.com/en/newsletters/Woodworking/5/4/article1-4.htm) (you can find the same info in other (http://www.toolsfromjapan.com/store/index.php?main_page=page&id=13&chapter=5) charts (https://www.sharpeningsupplies.com/Sharpening-Stone-Grit-Chart-W21.aspx) as well). Interestingly enough, in the picture I posted back of the blade had been flattened/polished to 3 um before bevel-tricking, so we're probably refining our backs to about the same degree. I then polished the back-bevel to 0.5 um.




I do not bother to put in all the work it takes to remove all the striations produced by the coarser stones. The 8000 seems to leave a few of its own, at least some new finer lines are visible after it is used.

[snip]

Now if someone can show me the ruler trick is the only way to get shavings in the one ten thousandths or less range, then I would be interested and if it ever comes to the point of my needing to take such a thin shaving, then I would likely give it another try.

I've been able to get 1/2-mil shavings out of surprisingly rough edges, but then again we should care about the wood that remains behind, not the part we remove. IMO the main benefit of a more refined edge is in surface quality. An edge that cuts more cleanly leaves a finer surface with less tearout etc.

With that said, you do implicitly raise a good point: How much is enough, and where does overkill begin? In my experience you get noticeable improvement down to ~1 um, though opinions vary - IIRC Steve Tindall reported improvement all the way down to 0.25 um. I use 0.5 for back-beveling for margin and because it's easier to control the beveling process on the finer, slower-cutting abrasive. As noted above the bevel is only a micron or two deep (along the axis "into" the photo), so it doesn't take many strokes even at 0.5 um.

[Patrick Chase]

Patrick; this notion that you are just polishing the back of the iron to produce a micro back bevel is misleading. If its practice is designed to create a secondary plane, then there is a requirement to remove, not polish the metal.

Are you suffering from the common misconception that polishing doesn't remove metal or change geometry? It does, as the picture I posted demonstrates.

There is no such thing as a magic "polishing abrasive" that somehow "rearranges" the metal without wearing it away as some have claimed. The 0.5 um CrO that you use could be used to create a bevel just like any other abrasive, albeit slowly as it's not very aggressive.

Hint: If your substrate gets darker, then metal is being removed and geometry is changing.

[Jim Koepke]

Patrick; this notion that you are just polishing the back of the iron to produce a micro back bevel is misleading. If its practice is designed to create a secondary plane, then there is a requirement to remove, not polish the metal.

Just for fun, let us say it is polishing the metal.

In my case the area will be no more polished by my finest stone, an 8000 Norton, than the rest of the back. So why bother?

It won't make my teeth any whiter. Nor will it make my cholesterol numbers any lower. Will it make the sharpness of any blade last significantly longer between honing sessions?

So far it seems it would take an extra step if not some extra equipment, read investment.

If it will not accrue any benefit to my work or increase production, what reason is there as to why the ruler trick should be given consideration?

jtk

[Stewie Simpson]

Jim; I noted within your post that your stones have not been flattened for a while. I see within your supplied photo you have worked a decent area back from the cutting edge, but it looks as though you were not able to extend that flatness to the full width of the cutting edge. Did you have any issues trying to create a burr along the full width of the cutting edge when working the back.

Stewie;

http://www.sawmillcreek.org/attachment.php?attachmentid=347916&d=1479685550

[Patrick Chase]

http://www.sawmillcreek.org/attachment.php?attachmentid=347916&d=1479685550

Wow, those are some pretty huge striations. Also, there's some obvious dubbing along the edge (evidenced by the way the reflections "bend" as they approach it), so I wouldn't describe that as "flat".

[Pat Barry]

347916

This is after stropping on leather charged with green compound.
Thanks for the picture. This clarifies significantly. Your comments regarding flattening the back left me with a completely different image in my mind than this. This looks like you are really not so concerned with a high degree of flatness. I also see quite a bit of camber. I don't see that as being overly compatible with the ruler trick.

[Patrick Chase]

Thanks for the picture. This clarifies significantly. Your comments regarding flattening the back left me with a completely different image in my mind than this. This looks like you are really not so concerned with a high degree of flatness. I also see quite a bit of camber. I don't see that as being overly compatible with the ruler trick.

Very true - you'd have to use a steep and deep back-bevel with an edge like that.

You can bevel-trick with camber by "pivoting" the blade as you work it to polish different parts of the edge, though I personally don't bother since my heavily-cambered planes (jacks, scrubs) don't need that degree of edge refinement to begin with.

[Jim Koepke]

I actually think that more of the curvature seen in the image is due to the cheapness of my camera and its lens than the geometry of the blade.

Even so, if my blade is as horrid as it may seem, it still does a pretty good job of cutting (slicing?) wood in a manner suitable for a smoothing plane.

jtk

[Stewie Simpson]

It should be pointed out that not all manufactured plane irons and chisels are uniformly flat along the full length of their backs. As a result there are occasions where some lifting is required to insure that that the forward 1/2 to 1 inch is in direct contact with the surface of the stone. That's a primary reason why its deemed good practice when working these backs, to apply some downward pressure with your forward fingers close too the cutting edge. Whether 1 chooses to use the Ruler Trick or not, what's has come out of this discussion are the real benefits in keeping the top surface of your honing stones within a tight tolerance of flatness. That in itself has some relevance to Derek's inquiry within another post, as to why you would bother keeping your stones flat. Out of flat stones may be seen as acceptable for working the bevel side of your plane iron and chisels, but that's clearly not the case when working the backs.

[Normand Leblanc]

Even so, if my blade is as horrid as it may seem, it still does a pretty good job of cutting (slicing?) wood in a manner suitable for a smoothing plane.

jtk

That's the more important. If my blade is cutting properly who cares what technique I used.

Interestingly, every time I've seen an old stone it was dished quite a bit. I have to presume that the woodworker of that time did managed to get his work done.

Normand

[Patrick Chase]

I actually think that more of the curvature seen in the image is due to the cheapness of my camera and its lens than the geometry of the blade.

I accounted for that when I analyzed Stewie's picture.

His camera does have a fair bit of barrel distortion (the fancy technical name for "fisheye effect"), and that accounts for the "bulging" along the top and bottom edges, for example. That's why I only remarked on the dubbing, because there's no way that lens distortion caused the reflections to suddenly "bend" just behind the edge. Barrel distortion is easy to spot and correct once you understand the underlying physics.

[Patrick Chase]

FWIW here's an example of a blade that can't be back-beveled, from a low-angle shave. I worked it to 1 um, but didn't lap out the slight hollow in the middle as it has no functional impact (it's actually beneficial inasmuch as it eases flattening). The rest of it is flat to within 1/5000", but has visible striations even in the polished parts. Note that I chose the lighting geometry to accentuate those. If I'd rotated the blade 90 deg or focussed on the reflections instead of the blade itself then they'd be undetectable.

Back-beveling would have allowed me to fully polish the part behind the edge with a reasonable amount of effort, but the shave has so little clearance that doing so would be counterproductive.

347952

[Patrick Chase]

Whether 1 chooses to use the Ruler Trick or not, what's has come out of this discussion are the real benefits in keeping the top surface of your honing stones within a tight tolerance of flatness.

100% agreed. The profile of the iron needs to be a straight line where it meets the cap iron. It doesn't matter whether it's flat, back-beveled, dubbed, etc along the lengthwise axis though, provided that it isn't "tilted" by more than the cap iron's undercut angle.

[Stewie Simpson]

FWIW here's an example of a blade that can't be back-beveled, from a low-angle shave. I worked it to 1 um, but didn't lap out the slight hollow in the middle as it has no functional impact (it's actually beneficial inasmuch as it eases flattening).

Patrick; apologies for asking this question, but why would you bother working to 1 um when you leaving the most critical area of the blades contact untouched with a slight hollow. I would have considered it a higher imperative to work that hollow out with a coarser grit before moving on to 1um, or at the very least reached a stage where you had a clearly defined flat surface that encroached the full width of the cutting edge.

Stewie;

[Graham Haydon]

Jim, cheap camera or not the back of your Iron looks fine. All I'm looking for is to be able to remove a burr quickly, yours looks free from a burr. Since looking at all the different options that others find success with I've just gone back to what I was doing before. Fine India, raise a burr, remove a burr light strop and back to work. My cap iron fits, I can plane, pare and chop with no issue. There is nothing wrong with any approach shown here but lots of the ruler, micro, diamond approaches feel like something from a science/engineering lab.

[Patrick Chase]

Patrick; apologies for asking this question, but why would you bother working to 1 um when you leaving the most critical area of the blades contact untouched with a slight hollow. I would have considered it a higher imperative to work that hollow out with a coarser grit before moving on to 1um, or at the very least reached a stage where you had a clearly defined flat surface that encroached the full width of the cutting edge.

Stewie;

I think you're misinterpreting the photo.

The part of the back adjacent to the edge is polished all the way across, as evidenced by its high reflectivity. The change in lightness across the edge is simply reflections of lighter and darker objects (my finger on the left, the top corner of the camera and another finger in the center, etc). If I had focussed on the reflections instead of on the iron then the part along the edge would pass for a mirror.

The hollow is the "hazy", less-reflective part in the center of the iron's back, far away from all 4 edges. Given that this blade is for a low-angle (bevel-up) shave, that hollow is literally hanging out in space. It's as unimportant as it could possibly be.

[Stewie Simpson]

Thanks Patrick.

[Kees Heiden]

Personally I am moving more into the "good enough camp". Maybe it is the kind of wood I am working on at the moment (mostly cherry).

I find that getting rid of the wire edge, cleanly, is the most important thing about working the face side. Whether it is truelly polished, or has a few scratches, seems to be rather unimportant in the grand scheme of things. At least for me. My guess is that most people who have trouble getting an edge sharp, have some wire edge remaining. Working the bevel and the face, back and forth, on a fine(ish) stone, then stropping on a leather strop with autosol, is working fine for me. The face of a planeblade needs to be flat from side to side for me, so the capiron sits tight all the way across. But I don't mind a bit of convexity lengthwise.

In a similar vein, I don't mind anymore when a chisel back is a bit convex. I have one or two chisels with flat or slightly hollow backs and use these when I really want it for jigged paring.

[Pat Barry]

I actually think that more of the curvature seen in the image is due to the cheapness of my camera and its lens than the geometry of the blade.

Even so, if my blade is as horrid as it may seem, it still does a pretty good job of cutting (slicing?) wood in a manner suitable for a smoothing plane.

jtk
No doubt a camera can create distortion but you could put the edge up next to a known straightedge to verify the camber. To your second point though, I put it in the category of whatever floats your boat. Everyone eventually settles on what seems to be a comprise of sorts that works for them. I suspect everyone has room to improve though.

[Warren Mickley]

I think the "ruler trick" would be a big time waster for a serious worker. It takes a lot more time to position the ruler, flatten and remove the ruler. As I mentioned here in July, in recent sharpening videos David Charlesworth spent six seconds on the back of a chisel, and 30 seconds for the plane iron when starting with picking up the ruler.

For a hobbyist or a collector who was expecting to prepare a new plane or plane iron every few months, the "trick" would be worthwhile.

I don't remember doing any jigged paring.

[george wilson]

Another one of those GREAT threads where you can argue how many angels can dance on the ruler tricked micro bevel!!!:)

You all need to stop PREPARING TO WORK (It is an easy trap to fall into !),and get some wood out and start making something.

Of course,talking about work is cheaper on lumber cost than actually USING IT!!!:):):) And,if your shop is not heated,it is more comfortable!!!

[Kees Heiden]

Of course, you shouldn't forget, most of us are sitting at work behind the computer. During lunch hour of course (or maybe a tiny little bit beyond that) and are just discussing what fancies us. No harm done....

[Prashun Patel]

Statler and Waldorf,

What is a bigger waste of time? Geeking out about the ruler trick, or throwing peanuts at the geeking out of the ruler trick?

[Jebediah Eckert]

Haha, so true. From now on every part of this thread will be uncontrollably read in my head in those voices.

[george wilson]

The bigger waste of time is the geeking out of the ruler trick. This is because after considerable time has been spent geeking t out,much less time is needed to toss peanuts at it!!:):):)

[Jim Koepke]

Another one of those GREAT threads where you can argue how many angels can dance on the ruler tricked micro bevel!!!:)

You all need to stop PREPARING TO WORK (It is an easy trap to fall into !),and get some wood out and start making something.

Of course,talking about work is cheaper on lumber cost than actually USING IT!!!:):):) And,if your shop is not heated,it is more comfortable!!!

I must agree with this.

My only excuse is my doctors do not want me working wood or otherwise until at least January.

jtk

[Robert Engel]

I only use it because it speeds up the sharpening so I can get back to work faster.

[michael langman]

An edge is an edge is an edge. Only the wood knows for sure!:)

[Patrick Chase]

Statler and Waldorf,

You know, this may be one of the few corners of the Interwebs where the audience is old enough to get that joke. If I said that at work I'd get blank stares (and I'd get laughed out of the building if I referenced the "Shakespearean fan fiction" characters (https://en.wikipedia.org/wiki/Rosencrantz_and_Guildenstern_Are_Dead) that inspired Statler and Waldorf).


What is a bigger waste of time? Geeking out about the ruler trick, or throwing peanuts at the geeking out of the ruler trick?

Hey, it takes a LOT of effort to maintain "serious woodworker" cred by continuously telling everybody else they're doing it wrong!

Seriously, George and Warren are right. This is a side-discussion of a side-discussion. Nothing to see here unless you're a geek.

[Brian Holcombe]

Those backs are very nicely done Patrick!

WRT the ruler trick; I've used it an ultimately done away with it, I find it easier to remove the burr without it, given a flat back.

I don't grind my bevels and that is why I find it to be frustrating. 1000~ will take away the wear, but when using the ruler trick I would need to grind heavily with a very rough stone first.

One more edit:

I like to search for very tiny imperfections in the edge by looking for spots that reflect light, I find the tiny microbevel to disturb my ability to do that.

[Patrick Chase]

I like to search for very tiny imperfections in the edge by looking for spots that reflect light, I find the tiny microbevel to disturb my ability to do that.

I find that the tip of my fingernail is more sensitive to those than are my eyes, but I can understand where you're coming from. The advantage of a visual check is that you don't have to worry about slipping :-).

[Brian Holcombe]

After 12-14 hours of woodwork slipping is an honest concern, lol.

I once ran a steel straight edge over one of my blades at the end of a day like that.....which then made the day even longer still.

[Stewie Simpson]

You know, this may be one of the few corners of the Interwebs where the audience is old enough to get that joke. If I said that at work I'd get blank stares (and I'd get laughed out of the building if I referenced the "Shakespearean fan fiction" characters (https://en.wikipedia.org/wiki/Rosencrantz_and_Guildenstern_Are_Dead) that inspired Statler and Waldorf).



Hey, it takes a LOT of effort to maintain "serious woodworker" cred by continuously telling everybody else they're doing it wrong!

Seriously, George and Warren are right. This is a side-discussion of a side-discussion. Nothing to see here unless you're a geek.

Patrick; just because some of the feedback has questioned the merit of using a back bevel (ruler trick) does not make that discussion a waste of space. Like everything else said within an open forum, you listen to the pro's and cons of what's been said , and then make a valued judgement based on whether to modify or continue using your existing technique. Just because George makes a statement suggesting the topic is a waste of space, doesn't mean the rest of the members have to scurry away like hermit crabs wanting to bury themselves in the sand.

Stewie;

[Stewie Simpson]

Those backs are very nicely done Patrick!

WRT the ruler trick; I've used it an ultimately done away with it, I find it easier to remove the burr without it, given a flat back.

I don't grind my bevels and that is why I find it to be frustrating. 1000~ will take away the wear, but when using the ruler trick I would need to grind heavily with a very rough stone first.

One more edit:

I like to search for very tiny imperfections in the edge by looking for spots that reflect light, I find the tiny microbevel to disturb my ability to do that.

Brian; I find your statement of having to use a very rough stone to apply the back bevel of interest. Could you clarify why your 1000 grit stone was not able to produce the micro back bevel.

Stewie;

[Brian Holcombe]

I see how what I wrote is a bit ambiguous, I meant I would need to grind away more of the main bevel to remove the back bevel when resharpening the blade. Normally I just remove the wear bevel.

[Stewie Simpson]

Thanks Brian; I understand your approach now.

Stewie;

[Stewie Simpson]

That's the more important. If my blade is cutting properly who cares what technique I used.

Interestingly, every time I've seen an old stone it was dished quite a bit. I have to presume that the woodworker of that time did managed to get his work done.

Normand

Normand; that's a worthwhile topic that deserves its own separate discussion as to the reasons why this seems to have been a common practice within older stones. I am not overly confident there is 1 single defining answer. As mentioned earlier, an out of flat stone may not necessarily pose a problem with the bevel side of the blade, but what steps were taken to address the flat side of the blade is a little unclear. Its quite possible that little attention was given to the back of the blade in those earlier days, suggesting the practice of prematurely removing the burred edge was a more favoured practice. I know in my fathers case, he tended to work the bevel side only with his combination stone, and relied on removing the burred edge by folding it back and forth against the leg of his Bib & Brace Overalls. http://www.hardyakka.com.au/bib-brace-cotton-drill-overall-81.html

Stewie;

[Normand Leblanc]

Stewie,

About a year ago, with a friend, we bought a large lot of tools from an estate. The man that had died didn't use his hand tools collection and they were bought from all over the place on a 30 years time frame and sharpened by many different woodworkers (as I have been told by his son).

In this lot there was ~100 planes. None of those blades had a flattened back, none.

Oh and we bought 13 router planes with blades as well.

Normand

[Stewie Simpson]

Stewie,

About a year ago, with a friend, we bought a large lot of tools from an estate. The man that had died didn't use his hand tools collection and they were bought from all over the place on a 30 years time frame and sharpened by many different woodworkers (as I have been told by his son).

In this lot there was ~100 planes. None of those blades had a flattened back, none.

Oh and we bought 13 router planes with blades as well.

Normand

Normand; that would indeed highlight why a lot of those earlier stones are out of flat. It should also be noted that a large majority of those earlier forged plane irons and chisels were not within a close flat tolerance during manufacture, and may go a long way to explain why more focus was placed upon the bevel side.

[Patrick Chase]

Patrick; just because some of the feedback has questioned the merit of using a back bevel (ruler trick) does not make that discussion a waste of space.

You're misunderstanding me: For someone like George or Warren this entire thread, including my initial post, is a waste of space. Fortunately they don't have to read it if they don't want to, and the subject made it pretty clear what the topic was so it's not like they were suckered in somehow.

[Normand Leblanc]

that would indeed highlight why a lot of those earlier stones are out of flat. It should also be noted that a large majority of those earlier forged plane irons and chisels were not within a close flat tolerance during manufacture, and may go a long way to explain why more focus was placed upon the bevel side.





My personal "theory" on this is, because the blades were so out of flat and all they had was oil stones, it would have taken forever to flatten those back so they didn't do it. Maybe they had some kind of strop...like your father?

I've flatten may be 30/40 of those and I've develop a technique for that. Using a DMT fine, a few swipes to get an idea how out of flat that blade was. If very bad, hammer it down (I've broken one blade doing this). If not, use the ruler trick to create a ~1/4" wide flat at the edge then increase the thickness of the ruler using a hard Arkansas. Every chip breaker was "sharpened" to match.

It was very quick and worked perfectly.

Normand

[Stewie Simpson]

Normand; I am always open to listening to alternate techniques, based on personal experience. Appreciate your feedback.

regards Stewie;

[Patrick Chase]

Before I comment I want to make it clear that I think that your results speak for themselves, so I would never suggest that you should change anything about your technique. As always there's more than one way to do it (tm).


Those backs are very nicely done Patrick!

WRT the ruler trick; I've used it an ultimately done away with it, I find it easier to remove the burr without it, given a flat back.

I don't grind my bevels and that is why I find it to be frustrating. 1000~ will take away the wear, but when using the ruler trick I would need to grind heavily with a very rough stone first.

If you needed to use a very rough stone to remove the back-bevel left by the ruler trick then you were applying a *much* deeper back-bevel than I do or than I think is needed.

If you refer back to the image in #1, the back bevel there is a bit less than 0.5 mm thick. It's at atan((0.25 mm shim)/(60 mm setback)) = 0.25 deg, so the edge is recessed from the back by at most 0.5*tan(0.25) = 0.002 mm = 2 microns. In other words, just barely enough to remove the striations from the last grit that was used during flattening.

#1000 is 10-15 um (depending on system), so even a #1000 stone is gross overkill for removing that amount of back bevel. I usually use ~3 um diamond paste when I want to remove the bevel, though more often I simply "freshen up" the back bevel at the same time as I work the face. Note that this also means that the blade-life impact of back-beveling is negligible.

[Pat Barry]

You're misunderstanding me: For someone like George or Warren this entire thread, including my initial post, is a waste of space. Fortunately they don't have to read it if they don't want to, and the subject made it pretty clear what the topic was so it's not like they were suckered in somehow.
They don't need to comment if the topic is of no use to them. Just because they poo pooh the subject doesn't mean it isn't worthy of discussion.

[Pat Barry]

I see how what I wrote is a bit ambiguous, I meant I would need to grind away more of the main bevel to remove the back bevel when resharpening the blade. Normally I just remove the wear bevel.
I don't see why you would need the grind the front bevel any more or less if you are using the ruler trick. That would be wasteful. I see for your situation though, not using it, that you in fact do need to grind away the wear bevel as part of your sharpening process.

[Brian Holcombe]

Diamond paste is going to cut a lot faster than what I'm using (India, ark or ceramic waterstones), so I have a tendency to start with a rougher grit than what might be required in a system which uses diamond paste.

I've been removing anything which adds time to a procedure, not so much initially, but in the process of working. Do I always dull an edge to the point where I want to work it on a 1000 grit stone on forward before returning to work? With planes, sometimes but not always. When I am finish planing something like a slab, I will take apart and hone the blade numerous times and that is when anything that complicates the process becomes something that one wants to remove from said process.

Most of the time I will dull a blade to the point where I want to completely rework it, from a rough stone forward, but on those times that I do not it is much easier to use a flat bevel and bevel-free back.

I think it is also worth noting that certain steels (A2) are going to be much easier to use with a back bevel.

[Brian Holcombe]

I don't see why you would need the grind the front bevel any more or less if you are using the ruler trick. That would be wasteful. I see for your situation though, not using it, that you in fact do need to grind away the wear bevel as part of your sharpening process.

Pat, for the simple reason that one wants to repeat the microbevel as originally created to avoid having it grow.

[george wilson]

I only mean to TRY fostering actually MAKING THINGS. That is how you get somewhere as a craftsman,really.

Theory is fine,and necessary,too, but sometimes it seems like the only thing that is discussed here.

I'll try to not poo-poo your discussions.

[Pat Barry]

Pat, for the simple reason that one wants to repeat the microbevel as originally created to avoid having it grow.
Sure, that makes sense. Thanks Brian

[Patrick Chase]

Pat, for the simple reason that one wants to repeat the microbevel as originally created to avoid having it grow.

You don't need to remove it to achieve that. Just give it a swipe or two on your favorite polisher to remove any wear bevel and you're good to go. You do of course need to use the same shim at the same distance from the edge to preserve the angle.

[steven c newman]

Ok....for one, I do not use a back bevel on my edge tools. Two, I don't even own the required "ruler" to use the ruler trick. Nor have I ever found the need to do a back bevel.

Been fun to watch all the arguments, though......need butter on the popcorn, though...

[Brian Holcombe]

I accidentially threw mine away about 6 months ago.

[Jim Koepke]

I only mean to TRY fostering actually MAKING THINGS. That is how you get somewhere as a craftsman,really.

Theory is fine,and necessary,too, but sometimes it seems like the only thing that is discussed here.

I'll try to not poo-poo your discussions.

I understand George, today I spent some time in the shop using the bandsaw and a few things my doctors would frown upon. Though nothing too heavy was attempted.

My theory is to keep it simple (actually not mine as it is an old theory, older than me). By my way of thinking there has to be a good reason to change what is working. My blades may be far from perfection, but they get the job done. I have tried a back bevel or ruler trick on some blades and wasn't impressed.

Until someone provides a good answer as to why it should be done or how it will provide improvement I think I will wait for Steven to get a bit more butter on the popcorn and then bum a bowl full from him.

jtk

[Phil Mueller]

Brian, the ruler or the popcorn?

[Stewie Simpson]

Jim; I believe this discussion has allowed the opportunity to put forth a case on for and against the use of the ruler trick. It has also been a civil debate compared to other sharpening discussions that have been brought up in the past. As Patrick rightly pointed out, the topic of discussion is clearly pointed out within the opening posts heading, and there has been no pressure placed upon any member to participate in this discussion if they consider the topic of no interest to them. Like every topic that finds itself on this forum, you have a number of choices available, you can ignore it and move onto another post that's serves your interest, you may have an interest in the discussion but are quite happy to not contribute other than to listen to what others have to say, or you may wish to participate within that discussion on the basis that your own experience has some important relevance.

regards Stewie;

[Brian Holcombe]

Brian, the ruler or the popcorn?

My ruler became a victim of my aggressive vacuuming. Recently my Sam Maloof pencil was also added to that list. If it gets vacuumed I weigh heavily its value, debating wether its merit is such that I should release it from dusty purgatory.

[Jim Koepke]

Hi Stewie,

The only concern of mine is we occasionally have a new member with questions concerning their sharpening ability. Before you know it there are recommendations about secondary bevels, ruler tricks and other methods.

I am in the KISS school, Keep It Simple Stupid. If a person has a grinder to produce a hollow grind, that is fine and helpful to the freehand sharpener. Other than that, my idea is to stay with a flat bevel and a relatively flat back. (My pictures may show my backs are not flat, but they are close enough to work.) Relatively being the choice of the user to just work 1/4" flat or 2". Once a person can get a good edge, then try some of the more sophisticated trickery of convex bevels, secondary bevels, tertiary bevels, back bevels or ruler tricks. When someone new comes along and has done all of that, where would you have them start to fix a problem if their blade still doesn't take shavings. (Yes, I realize you can not have a hollow grind and a convex bevel on the same blade without really fighting the laws of reality.)

To me the problem rests with the typical male reality, if a little is good, then more must be better. I have received blades on auction purchase with the blade ruler tricked or back beveled for a quarter inch or more.

I have yet to see much benefit to the ruler trick. If it is as minute as Patrick suggests, will it be enough to remove a significant wear bevel? What about the next time will the ruler trick angle have to be increased?

jtk

[Stewie Simpson]

Jim; appreciate your views and I personally understand where your coming from with the KISS philosophy. I have not hidden the fact that I don't use, or personally agree with the principles of using a back bevel. But I also recognise and accept that within this forum there are those who's views are quite different.

regards Stewie;

[steven c newman]

The warmed up Butter is ready......need any salt?

[Patrick Chase]

Jim; appreciate your views and I personally understand where your coming from with the KISS philosophy. I have not hidden the fact that I don't use, or personally agree with the principles of using a back bevel. But I also recognise and accept that within this forum there are those who's views are quite different.

regards Stewie;

As you and I have both noted, tools like chisels and low-angle shaves require a good edge with a flat (un-bevelled, un-dubbed) back, so IMO the ability to implement that is a foundational skill that everybody must develop. I object just as strenuously as you to using the bevel trick as a "shortcut" to avoid learning to do that. As with many things you have to have the fundamentals down before you can experiment with situation-specific variations.

Beyond that I agree with your point that there's More Than One Way To Do It (tm). As I've said a couple times, the purpose of this thread wasn't to argue that anybody should change their ways, but instead to try to clear up some seeming misconceptions about what (at least some of) the folks who use the bevel trick are doing and why.

This has indeed ended up a refreshingly civil discussion - thank you for helping to make that happen!

[david charlesworth]

Greetings,

I have found this thread most interesting as it contains many of the objections routinely raised!

My You Tube channel has a short video about how I do the ruler trick, and I hope this may be of some interest.

I have been doing it to all blades except chisels for at least 30 years, and can see no disadvantages at all.

Best wishes,
David

[david charlesworth]

Here is even the link

https://www.youtube.com/watch?v=nykVPKbUGTo

David

[Devon Curtis]

Howdy Devon and welcome even though you have been hanging in the shadows for a few years.

Not sure if I would know if any of my blades were sori afflicted. Can it happen to blades in metallic planes?

jtk

Thanks for the warm welcome. Like you say, I've lurked for a while, and don't have a lot of time (or possibly knowledge) to contribute.

Sori is a curvature along the length of a blade, typically curving out towards the bevel side of the blade. I'm sure it can happen to blades from western or metal-bodied planes, but it may not be as much of an issue with them. Sori is a problem in kanna blades because it leads to poor fit between the blade and the upper rails of the mortise it fits into. Worst case, it can cause the edge to dig into the rails. With a chipbreaker, lever cap, and frog affixed to or in contact with the blade, I don't see blade curvature being as big a deal with a metal-bodied plane. I could be wrong, though.

[Devon Curtis]

Yep, I've done that as well, though I think you may be overestimating the degree of bevel I applied when you say "drastic". It was 1/4 deg (10 mil shim stock set 60 mm back from the edge).

How thick is your UMHW tape and how far back from the edge?

More broadly I'm personally not a fan of using back-beveling as a substitute for flattening, because you then lose control of the geometry of the bevel region leading to trouble with cap-iron mating. I think it works best as a polishing aid *after* flattening.

To clarify, I was referring to using an actual ruler when I said 'drastic.' The UHMW tape I use is 5 mil thick, and I haven't measured exactly how far back from the edge I apply the tape. I adjust that based on the condition of the blade. I basically just use the tape to establish a flat area at the edge, that I can then work further up the blade as I continue to flatten the back without the tape. After a flat is established, and the blade is workable, I typically stop using the tape.

I agree with you regarding back-bevelling as a substitute for flattening. I find the UHMW tape helps me get to flat, or at least planar, faster than without it.

[david charlesworth]

I don't see ruler trick as a substitute for flattening.

It's good to flatten on something like 800g stone.

RT just avoids polishing large ares of metal which do no cutting.

Also increases probability of honing away wire edge.

best wishes,
David

[Kees Heiden]

I see the rulertrick as a solution in search of a problem.

[Charles Guest]

I'm not sure how one could keep a back from becoming highly polished over time and by that I mean a few months of concerted woodworking. And if you're in a hurry 3M and others make very fine grit abrasives that make imparting a mirror shine to tool steel child's play - ten minutes tops per iron even less for chisels. In light of this any workarounds seem quaint and outdated at best.

I'm not necessarily in the camp that believes a mirror shine is an absolute necessity (if it is somebody will have to explain Chippendale, et al.), I don't guess it hurts, but it doesn't matter really as it's easy enough to impart and not just an angstrom's worth at the edge. Ten dollars' worth of auto body sandpaper and *problem* solved.

[Warren Mickley]

Greetings,

I have found this thread most interesting as it contains many of the objections routinely raised!

My You Tube channel has a short video about how I do the ruler trick, and I hope this may be of some interest.

I have been doing it to all blades except chisels for at least 30 years, and can see no disadvantages at all.

Best wishes,
David

David says he sees no disadvantages. As I pointed out on this forum in July, the major disadvantage is the extra time needed to execute the "ruler trick", thirty seconds in his December 2015 video. As I recall the time to sharpen a plane iron was in excess of two minutes and that does not include any time for grinding, which he obviously does, or for stropping which he apparently omits.

A minor disadvantage is the angle of the edge; David shows a 35 degree bevel angle plus a 2/3 degree back bevel. When I experimented with bevel angles forty years ago, I noticed a poorer result for bevel angles of 33 an 35 degrees (as opposed to 30). 35 2/3 is uncharted waters for me.

I watched Charlesworth's 16 minute video (November 2016), which he referenced in this thread. In that video he mentions that Rob Cosman, Tom Fidgen, and Chris Schwartz also advocate the "ruler trick". What else do these fellows have in common with David? They are in the business of teaching beginners how to work wood. They have income derived from selling books, videos, classes. It seems that they are not so much teaching teenagers, hoping to follow the trade, as older guys who have sat in offices for years. Videos which show techniques that might frustrate an older guy are not profitable for these fellows.

[Patrick Chase]

David says he sees no disadvantages. As I pointed out on this forum in July, the major disadvantage is the extra time needed to execute the "ruler trick", thirty seconds in his December 2015 video. As I recall the time to sharpen a plane iron was in excess of two minutes and that does not include any time for grinding, which he obviously does, or for stropping which he apparently omits.

A minor disadvantage is the angle of the edge; David shows a 35 degree bevel angle plus a 2/3 degree back bevel. When I experimented with bevel angles forty years ago, I noticed a poorer result for bevel angles of 33 an 35 degrees (as opposed to 30). 35 2/3 is uncharted waters for me.

2/3 is on the high side, and IMO you don't need that much to achieve good polish at the edge. Charlesworth's reference technique corresponds to ~1/2 deg (assuming your "thin ruler" is about 1/2 mm thick) and I use 1/4 deg.

Also, when you experimented with bevel angles did you keep the clearance angle constant? If not then your results aren't necessarily relevant to this discussion as you would have had a confounding variable in play that isn't an issue here.

[david charlesworth]

Well I am pleased that some more of the prejudices have surfaced.

Kees,
Many people work the back on the surface of a waterstone. It goes hollow, and the wire edge is no longer satisfactorily honed away on a flat polishing stone, hence the need for stropping. RT is a simple solution for this problem.

Warren's stopwatch detects slowness of some seconds. So what?

The idea that he will be able to distinguish between an edge of 35 degrees and 35 & 2/3 degrees is absurd.

Best wishes,
David

PS I was hoping to encourage people to look at my demonstration of RT at

https://www.youtube.com/channel/UCQg_yua727tzXh1t6BFLjEQ/feed

[Pat Barry]

A minor disadvantage is the angle of the edge; David shows a 35 degree bevel angle plus a 2/3 degree back bevel. When I experimented with bevel angles forty years ago, I noticed a poorer result for bevel angles of 33 an 35 degrees (as opposed to 30). 35 2/3 is uncharted waters for me.


I suspect your experimentation 40 years ago was with respect to bevel angle only with a typical Stanley 45 degree bed angle bevel down plane and what you experienced was decreased edge life, correct?

[David Eisenhauer]

David: I had not previously been aware that you had some You Tube content available before this and was glad to see some of your experience displayed for others to evaluate. Thanks for putting it out there.

[david charlesworth]

David,
I am so glad you have enjoyed it.

David C

[Charles Guest]

A honing stone so out of flat that nowhere on its two broad surfaces (top or bottom) will it reach the burr on the flat side of a plane iron is in serious need of maintenance or replacement, not a trick or workaround. Help me understand how otherwise extraordinarily well-equipped operations find themselves consistently in this state of affairs and not once every fifth blue moon or so. In the time it took to refine this technique and post YouTube videos, write articles, etc. then stone maintenance could have occurred rendering the entire 'trick' moot.

[Warren Mickley]

I suspect your experimentation 40 years ago was with respect to bevel angle only with a typical Stanley 45 degree bed angle bevel down plane and what you experienced was decreased edge life, correct?
No, I did both bevel angle and bed angle experiments. I was already making planes that that time. I'm a little foggy on this, but I would say the symptoms of not enough clearance are a little different from symptoms of too great a bevel angle.

In the 16.23 minute video, now linked to twice in this thread, Charlesworth himself mentioned the 2/3 degree bevel. Likely I couldn't tell the difference between a 35 and 35 2/3 cutting edge, but I certainly could tell the difference between 35 and 30. Charlesworth calls the extra time issue a spurious argument. Maybe if you make videos for a living. He calls the "ruler trick" proponents "adventurous" compared to the "traditionalists". My impression is that the "ruler trick" and the sharpening jig are designed to take the risk of failure from beginning sharpeners. Traditional technique might be for someone more adventurous.

[Pat Barry]

No, I did both bevel angle and bed angle experiments. I was already making planes that that time. I'm a little foggy on this, but I would say the symptoms of not enough clearance are a little different from symptoms of too great a bevel angle.
Thanks for clarifying this Warren.

[Brian Holcombe]

A honing stone so out of flat that nowhere on its two broad surfaces (top or bottom) will it reach the burr on the flat side of a plane iron is in serious need of maintenance or replacement, not a trick or workaround. Help me understand how otherwise extraordinarily well-equipped operations find themselves consistently in this state of affairs and not once every fifth blue moon or so. In the time it took to refine this technique and post YouTube videos, write articles, etc. then stone maintenance could have occurred rendering the entire 'trick' moot.

I'm not a user of the method, but it has absolutely nothing to do with not being able to maintain a flat stone.

[Stewie Simpson]

A honing stone so out of flat that nowhere on its two broad surfaces (top or bottom) will it reach the burr on the flat side of a plane iron is in serious need of maintenance or replacement, not a trick or workaround. Help me understand how otherwise extraordinarily well-equipped operations find themselves consistently in this state of affairs and not once every fifth blue moon or so. In the time it took to refine this technique and post YouTube videos, write articles, etc. then stone maintenance could have occurred rendering the entire 'trick' moot.

Charles; the RT method is nothing less than another option available to the woodworker. No different that of freehand vs honing jig. No different to that of abandoning the traditional use of honing stones, in favour of an assortment of 3M abrasives.

In my personal case;

Do I rely on honing stones; yes.
Do I routinely flatten my honing stones; yes.
Do I restrict myself to freehand honing; no.
Do I use the R/L method; no.
Do I always rely on the advise given on ww forums; definitely not.

Stewie;



I'm not sure how one could keep a back from becoming highly polished over time and by that I mean a few months of concerted woodworking. And if you're in a hurry 3M and others make very fine grit abrasives that make imparting a mirror shine to tool steel child's play - ten minutes tops per iron even less for chisels. In light of this any workarounds seem quaint and outdated at best.

I'm not necessarily in the camp that believes a mirror shine is an absolute necessity (if it is somebody will have to explain Chippendale, et al.), I don't guess it hurts, but it doesn't matter really as it's easy enough to impart and not just an angstrom's worth at the edge. Ten dollars' worth of auto body sandpaper and *problem* solved.

[Charles Guest]

I'm not a user of the method, but it has absolutely nothing to do with not being able to maintain a flat stone.

I think a more thorough reading of the posts in the thread is in order. According to David Charlesworth it has everything to do with the condition of the stone:

Kees,
Many people work the back on the surface of a waterstone. It goes hollow, and the wire edge is no longer satisfactorily honed away on a flat polishing stone, hence the need for stropping. RT is a simple solution for this problem.

[Charles Guest]

With regard to the photo in the original post, it would take maybe three minutes, five at the outside, to polish a good half inch or more of the iron with diamond paste or other modern abrasive to the same degree of polish as the narrow strip in the photo. You'd be done for the next five year's worth of work with five more minutes' work. Easy calculus for me. Why tediously polish the little strip time and again when it's easy enough to polish further up the cutter, once? I'm baffled that somebody would prefer to work this way day in and day out.

If the stone is not reaching the burr then maintain the stone like one would any other tool that requires periodic maintenance of some sort.

[Stewie Simpson]

It would take maybe three minutes, five at the outside, to polish a good half inch or more of the iron with diamond paste or other modern abrasive to the same degree of polish as the narrow strip in your photo. You'd be done for the next five year's worth of work with five more minutes' work. Easy calculus for me.

Charles; if that post was aimed at me, then do me the courtesy of addressing my name.

Stewie;

[Charles Guest]

Charles; if that post was aimed at me, then do me the courtesy of addressing my name.

Stewie;

Not aimed at you. Getting used to the format of this forum. It was in response to the photo in the original post.

This technique is simply not needed in the era of modern abrasives, or probably ever. I suspect the last 1000 years+ or so of Asian craftsman would not recognize it as something necessary because of, or due to, rapidly eroding honing media.