Tag Archives: how to pare leather

New! Redesigned 151 Spokeshave for Leatherwork with Shaving Collector

modified 151 spokeshave

Modified 151 Spokeshave with shaving collector. It also makes a convenient stand when flipped upside down.

modified 151 spokeshave2

Note that the shaving collector does not interfere with thumb or forefinger placement.

English trained bookbinders often use a modified spokeshave for long shallow bevels on the turn-ins, reducing the thickness in the spine area of a full leather binding, preparing a new piece of leather for rebacking, and for beveling binder’s board.

I’ve improved the modified Stanley 151 spokeshave that I make and sell by adding a shaving collector. I first saw this on a spokeshave  James Brockman was using in 1990. I can’t quite explain why it has taken me so long to get around to making one for myself — I’ve been busy??? He kindly shared details of the design with me, and mentioned he first saw this while working at Roger Powell‘s shop in the late 1960’s or early 1970’s.

The shaving collector really speeds up work with the spokeshave, since you don’t have to stop and clean off stray shavings every couple of minutes, and they don’t get trapped under your leather, which can cause tearing or holes. Additionaly, it is easy to dump the full collector into the trash.   More information about spokeshaves for leather.

Other modifications to the spokeshave include: reducing the effective cutting angle by grinding the base, truing the adjustment knobs, rounding and lessening the surface area of the sole, opening the mouth, flattening the blade bed by filing and filling with epoxy, flattening the blade cap, and replacing the thin chrome vanadium original blade with a Lee Valley PM-V11 one. This blade is reground to a lower angle, sharpened, and the corners slightly rounded to prevent ridges formed in the leather. All of these modifications make the spokeshave a much more precise instrument and reduce chatter

Even if you rough out the leather with Scharffix or Brockman leather paring machine, this spokeshave can quickly help reduce the ridges and unevenness the results from overlapping cuts and blade changes if you are working on large pieces. It is also essential for gradual bevels wider than the width of a double edge razor blade. And it is a lot of fun to use.

MODIFIED 151 SPOKESHAVE: $275.00     How to purchase

 

Razor Blade Planes: Tips on Using Them to Pare Leather

In part one of this blog post, I presented an overview of a variety of razor blade planes. Here, guest blogger Eric Alstrom will share some tips for using these planes to pare bookbinding leather.

Eric Alstrom received his MILS in 1989 at the University of Michigan School of Information and Library Studies. After graduation, he apprenticed under James Craven at the University of Michigan’s Bentley Historical Library for four years. He later became Ohio University Library’s Collections Conservator. In 1998, Eric moved to New England to become Dartmouth College’s first book conservator. Currently, Eric is Head of Conservation at Michigan State University Libraries’ Wallace Conservation Laboratory. Eric also teaches binding and book arts at regional workshops. While at Dartmouth he expanded the popular Book Arts Workshop, which had focused solely on printing, into binding and artists books. He now teaches book arts and binding for the MSU Residential College for the Arts and Humanities. His design bindings and artists books have been exhibited both nationally and internationally. Eric has been a member of the Guild of Book Workers since 1993, has served on the board of directors since 2002. To view some of Eric’s design bindings, artists books and conservation work, please visit http://webalstrom.ftml.net/bookworks

  The Wil-Kro razor blade plane.

I was first introduced to the Little Giant when I was serving my apprenticeship with James Craven at the Bentley Historical Library at the University of Michigan. He had a Little Giant and showed me how useful it was for paring leather As I remember (and it has been many years ago), Jim did all his paring with either his paring knife or the Little Giant. In fact, I don’t remember Jim ever using a spokeshave while I was apprenticing with him and the early model Scharfix was rarely used. In the years since my apprenticeship, I have always looked for a Little Giant and garage sales, antique shops and the such. I never was able to find one and adapted my paring technique to include a balsa wood plane (a plane similar to the Little Giant, but made of plastic, rather than metal with a proprietary blade, not a standard razor blade), a spokeshave, and of course my trusty English paring knife.

After a conversation with Jeff Peachey at the Tucson GBW Standards in 2010, he said he ran across these from time to time. I asked him to let me know when he next found one because I would gladly buy it. Fortunately, he found one rather quickly and I have been happily paring away since. What he actually found was a Wil-Kro model, which from what I can tell is pretty much identical to the Little Giant. The Wil-Kro can be assembled with the front base shortened, which may be useful for planing curved wood, but it is not suited for leather paring.

.The Wil-Kro razor blade plane taken apart, showing the blade assembly. Note the curved blade bed.

I immediately started paring with my Wil-Kro as soon as I got it; I have not modified it at all. A razor blade fits over a screw and onto a ridge so it is held exactly in the same place. The front of the plane that clamps the blade is curved so the blade has a very shallow angle. The blade protrudes evenly beyond the base about .008”, or just under the thickness of three pieces of .003” thick mylar.

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The blade extends about .008″, roughly the thickness of heavyweight paper.

Since double edge razor blades have two edges, I mark mine “1” and “2” so I make sure I don’t use the same edge twice. Just like a paring knife or spokeshave, how long a blade lasts really depends on the leather. When the blade no longer glides easily and shaves off the leather, it is time to change. Another sign to look for is if the leather looks more like dust rather than shavings. To use a razor blade plane, first, prep the leather – pare all edges before using the razor blade plane, same as if using spokeshave or Scharfix. Use a flat surface which is larger than piece of leather, such as paring stone or other surface used to pare leather. You can clamp (or tape) down the leather or hold it with one hand. For smaller pieces (e.g.. spine and corner pieces), I prefer to hold it down with one hand so I can turn the piece around or change angles easily. This is a big advantage over a spokeshave, which takes two hands to operate. I find the razor blade plane best for smaller areas, such as a piece of leather for a spine.

.Paring with the Wil-Kro razor blade plane.

The action is similar to a spokeshave, whereas you hold the plane at approximately 45º to the forward motion, which is called skewing the blade. Don’t apply to much pressure, at least not at first. See how the leather will pare: some leather pares almost by itself, other leathers will need more downward pressure to get the blade to shave anything off. I generally work parallel to the spine, not across the skin (except of course when you are paring the fore edges for a full leather binding).

.Some leather parings made with the Wil-Kro.

Put the plane on the leather a little bit further back than where you want to start the thinning (similar to a spokeshave). Start to move towards the edge and apply pressure as necessary, depending on toughness of leather. All action is done by pushing the plane away from you (same as spokeshave). I start in the center of the edge I am paring and move my plane gradually towards one outside of the piece of leather then back towards the other edge. Don’t always start this process the same place or you are more likely to have uneven thickness in the leather. For example, when paring along the head for a full-leather binding, I might start midway between the spine and the corner of what will be the turn-in on the back cover. As I pare, I move the plane towards the corner a little bit after each stroke. Once I reach the corner, I slowly work my way back to where I started and then all the way to the spine. I’ll clean out the leather shavings and start again. But this time, I’ll start right next to the spine and work towards the corner and back. Then for a third pass (if needed, always check often!), I’d start near the corner. As I move towards the edge, I increase the pressure a bit to thin the leather more along the edge. You have to be careful, though, because you can easily shave through the entire thickness. I find the edges I am working parallel to are more vulnerable to this than in the middle. That said, I will sometimes “tip” the plane as I move towards the parallel edge to thin down that edge. I don’t actually tip the plane, but I put more pressure on the side that is adjacent to the edge.

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The Wil-Kro in action.

I find the razor blade plane very useful tool in the leather paring arsenal. It won’t replace a spokeshave (for efficiently paring large areas) or the Scharfix (for exact work such as onlays and labels) and definitely not the paring knife (for edge paring), but it has its place. For smaller pieces of leather, such as a spine for a leather reback, I find it better than a spokeshave and easier to use. For larger pieces, it can be useful along side the spokeshave for thinning out the corners or along the headcap area. Care must be taken because it can shave through the leather, but with practice and mindfulness, this shouldn’t happen any more often than with any other leather paring tool. The Little Giant (and other similar razor blade planes) aren’t the easiest to find, but they are worth the search.

Thanks Eric!

Razor Blade Planes: An Overview

INTRODUCTION

There are three fundamental techniques of paring leather in bookbinding: using a paring knife, using a modified spokeshave and using a paring machine, such as the Fortuna, Schar-Fix or Brockman. Often various combinations of these methods are used. Learning how to pare leather not only requires learning the technique of using a knife or spokeshave, but also the skills of how to keep the knife or blade sharp. The Brockman or Scharf-Fix alleviates the need to learn how to sharpen, although some thrifty bookbinders do resharpen their double edge blades. These paring machines are best suited for making small, thin flat pieces of leather — generally for onlays, labels, quarter bindings — rather than achieving a long, gradual bevel necessary for rebacking or English style full leather bindings.

There is a fourth, somewhat obscure method of paring leather which uses a razor blade plane.  There are numerous types of these planes, dating from at least the 1950’s until today. Originally, they seemed marketed to the home handyman, now most are marketed to model makers.  But at some point in time, bookbinders discovered these planes.

I’ve found little information about the history of using these planes on leather. Jim Craven, a bookbinder in Ann Arbor, Michigan, reports he recieved a Little Giant in the 1960’s, and is not sure when he started to use it on leather.  Judith Ivry, bookbinder and conservator, says they were somewhat of a craze in the 1980’s in New York City.  Occasionally I meet a bookbinder who uses, or has used them.

This post contains observations about these planes. American, German, Dutch and English versions are represented. Next week, in part two, guest blogger Eric Alstrom, Head of Conservation at Michigan State University, will present some tips for using razor planers on bookbinding leather.

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LITTLE GIANT

 Popular Mechanics, Sept 1956. p. 78

This is one of the most common, and better made than most. As far as I have discovered, this is the first oxymoronically named tool. The logo is well done, consisting of a curious kneeling ‘little giant’ supporting its own name that is shaped reminiscent of a dumbbell. This logo is a registered trademark, and the plane I have has patent pending cast on it. The instruction sheet lists it registered with  patent number  2,781,804, which was filed in 1955 and granted in 1957. I’ve seen at least two versions of the instruction sheet.

The two planes come neatly boxed, one for curved surfaces and one for flat.  The version with the flat sole is most suited to paring leather. If you are curious about using a razor blade plane, the Little Giant would be my first choice. Mine functions reasonably well with no alterations. The Little Giant is manufactured to a higher quality, with a more precisely ground sole and overall more solid feel than other planes I have tried. The flat model has a unique recessed finger area for positioning the angle and depth of the blade, while preventing fingers from making contact with the blade when planing. The curved model has two angles, one quite sharp, one more gradual, so the two planes can be used in three different planing configurations.

The box is printed, “Uses old razor blades” and the instructional sheet includes directions on how to resharpen double edge razor blades, although it is a bit difficult to understand how these very basic instructions could be of much help to a novice sharpener, especially one who had purchased a razor blade plane possibly in an attempt to avoid having to learn how to sharpen a blade in the first place. The finger position holding the blade looks frighteningly dangerous and seems to be putting a 45 degree bevel on the blade.

These sharpening instructions, from the late 1950’s,  which accompany the Little Giant are perhaps the earliest illustration of the  Scary Sharp sharpening method. They repeatedly mention using emory paper to resharpen double edge razor blades. But is Scary Sharp just using abrasives mounted on a paper of film substrate, or is it using a progression of these?

The informational sheet included with Little Giant planes shows three vignettes of the plane in use: a man trimming a door, a woman shaving down a drawer, and a boy making a model airplane. This is a tool not only for the man of the house, but the entire family. Note that it is advertised as being “sharp as a razor”. Yes,well, it is a razor.

Roughly 75% of the razor blade planes I have found appear unused, in the original box. The presence of so many “NIB” razor planes also suggests that they were likely used, or attempted to be used once or twice, then returned to the box. Perhaps the few beat up ones without boxes — a rarity — will prove desirable to collectors. The Little Giant is the only plane that I have seen that was painted; there is a light green, a darker green, a blue, and some are natural aluminum or pot metal.

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WIL-KRO RAZOR PLANER

Billboard, Oct 22 1955

The Wil-Kro (sometimes spelled Wilkro, even on the original box) is the most commonly found razor blade plane, in my experience.  It also works well in leather with little or no tuning. While some users may be content with the three blade configurations of a Little Giant, a Wil-Kro owner gets four:  a  flat sole, a bull nose, a chisel and a curved sole plane. It is one of the smaller razor blade planes, the most innovative in design, and quite comfortable to use. The blade depth is a slightly difficult to adjust on my examples, since the blade cap is actually part of the plane. A $2.50 price sheet is boxed with the model I have, although perhaps many enterprising home handymen took advantage of the discounted price of $72.00 for a gross! The small piece labeled “Fig. 8” below is often missing on planes I have seen for sale — examine the contents of the box carefully. This piece is used in the plane configuration Figure 4 on the instruction sheet below, useful for wood, but not really for leather.

The Wilkro patent  #2289504

Granted in 1942, the patent emphasizes many of the clever design features of the multipurpose handle which also secures the blade. This is the only razor blade plane I have that has the patent number stamped on the plane body, and it is the most innovative design. The patent application later notes that the blades are similar to the blades used in safety razors, but slightly different. In the instructions provided with the plane, however, ordinary double edge razor blades are recommended. The tightening knob evidently underwent some refinements during production, and has a much more elegant, almost horn like shape which is easier to align and tighten than the wing nut on all other planes. Since the body of these planes are essentially in two pieces, some users feel they are not as rigid as one piece models, though this does not seem to be an issue when using them on leather. The patent application describes this as a woodworking tool, which is perhaps its most ill suited use.

The Wilkro came with fairly detailed instructions.  The necessity for written instructions seems to indicate either a new or complex tool, or marketing to a realtively amateur market. Like the Little Giant, use in homes, possibly as a one plane fits all, seems to be the main focus for sales. Unlike the Little Giant, users of the Wilkro are advised to replace dull blades rather than resharpen them. Since the advertising I have found for both of these are roughly contemporaneous, I wonder if there was stiff competition between the two in the mid 1950’s?

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The plane also came with this Certificate of Assurance.  It certifies that the Wil-Kro is percision made and will give many years of service.  It then guarantees this performance for exactly fifteen days from the date of purchase.  The overall size of this cerificate (152 x 71 mm) is almost exactly the same as a dollar bill (157 x 66mm) and the green ink and boarder decoration also seem to visually imply paper currency. Most Wil-Kro boxes list “Craft Master Tool Co.” as the manufacturer and the contact for the warranty. One box I have, however, does not include a warranty and lists “Winston Sales Co.” as the manufacturer on the outside. Otherwise the boxes are identical.

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SELECT PLANER

The Select seems to have undergone at least three packaging styles, and one major redesign.  I think the version pictured above is earlier than the ones below.  The packaging is similar to the Wilkro: the company information on one end of the box is almost identical in layout, the “horn” tightening nut is similar, and even the complex shape to the blade holder all recall the Wilkro. In this version, the chisel blade position at the front is functional, later it is abandoned.  The complex flat blade holder design is also simplified in the versions below. The distinctive outward flair to the sides of the plane remain constant, however.

This is a somewhat interesting tool, the example I have has two different blade configurations, a flat and curved located at the back of the plane.   The instructions, located on the side of a bag containing blade caps and wing nuts, show two different types of assembling the plane. The box states the plane is for “Tradesmen, handymen, hobbyists, housewives.” Like the Little Giant, somewhat early marketing towards women. This plane feels distinctly larger than the previous two, and doesn’t seem to work quite as well on leather.

On one end of the exterior box the plane is shown operated a third way, like a scraper or chisel plane. The plane itself seems to have a vestigial place for a stud. But is it broken, did someone removed it, or were there manufacturing difficulties?  Made in USA, no patent. There is a nice slideshow of this plane on Howies Antiques, showing the same lack of a front scraper attachment. The packaging advertises it it useful in wood, plastic, leather, rubber tile, linoleum and pressed wood.  To me, this one looks later than the Wilkro or Little Giant, perhaps even 1970’s? Another version of the Select, with ribbed finger grips on the side and a fancier knob was also made.

http://www.petermcbride.com/magnum09/img/magnum_058.jpg

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RAZA-PLANE

http://www.flickr.com/photos/galoot_frank/1624654074/

This is the earliest razor plane (if it uses a disposable razor blade) I have seen. Also the only one made from cast iron, the owner reports 3 5/8″ long, 2″ wide.  This is a very common size for most razor blade planes.  I’m unclear how the blade clamping mechanism might work. There is a general thread about razor blade planes in the Old Tools Archive.

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ZIP PLANE

Modelflight

Made in England.The blade looks pretty easy to adjust from the sides. Marked Patent Pending. Like the Wil-Kro, the proper direction for planing is cast into the plane, which to me indicates a very low expected competence from users.

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DAVID (COMBI) PLANE

Dutch. Often regarded as one of the better old razor planes by model airplane makers. Three blade positions, and uses a wing screw rather than a wing nut. The 45 degree chamfer at the end, when the blade is in a chisel position,  let the blade be used as a knife. The sole may have too much surface area to work well on leather. Reportedly there is a plastic piece that deteriorates relatively quickly. The David is for sale at sky king rc products.

 Modelflight

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FIX PLANE (?)

German? This tentatively identified plane is perhaps the most elegant and ergonomic in form, to my eye.  It functions as a flat and chisel plane. It looks quite comfortable to grasp, and the blade is accessible from three sides for adjustment.

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SOLLINGEN BALSA PLANER

http://www.rcgroups.com/forums/showthread.php?t=183330

German. I’ve also seen this called the “Amati model ship planking razor plane“. Geometric styling.  The blade cap appears to rest on a cast stand, possibly concentrating pressure on the front edge, similar to ‘real’ planes.  The description claims this makes the blade rigid enough to plane across the grain, as well as with it. This raised area at the end of the blade cap may protect the users hand from jamming into the wing nut. The mouth on this one looks rather large for use on leather. Available from  A2Z Corp.

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MASTER AIRSCREW 4100 RAZOR PLANE 

Perhaps the most basic design imaginable. These are available from many retailers and seem to be the preferred new model among model makers. Simply designed. They use a proprietary double edge blade which is very thick at .017″ — most double edge razor blades are .oo4″-.008″. The two screws behind the blade seem to adjust depth and angle, which would make replacing the blade to the exact cut as the previous one much easier, though I wonder if the screws might damage the blade edge? The mouth looks too big to work well on leather.

Eric Alstrom adds that these are made of plastic, and “I never put it in the same class as the Little Giant.  Both for how it works and how it is made.  I’ve used it now and again for touch up, but the angle of the blade isn’t low enough to pare very effectively.  Mine came with a half dozen blades or so and I’ve only marked about half of them as used, so I haven’t used it that much.  You mention the “proprietary double edge blade” which is true they are proprietary, but my blades are only single edge.  The adjustment screws push against a flat edge.  I got mine about 20 years ago, so maybe they have changed since then.”

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LEE VALLEY RAZOR BLADE BLOCK PLANE

The Lee Valley is made in Germany, and has a rear handle that doubles for planing curved surfaces which is perpundicular to the usual planing position. The wingnut to tighten the blade is visible on the back of the handle.  The consensus among woodworkers is that  the plane is useful for basa wood, and maybe other some very soft woods, but not as a general use plane. It features three variable positions, normal use, as pictured below, as a chisel plane with the blade at the front, and curved at the heal.  Having a blade potentially positioned right on your hand seems like a poor design choice. Lee Valley advertises it as a plane to use when you don’t want to use your good plane, like on paint. The sole may have too much surface area to work well on leather.

Lee Valley, Razor block plane

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ARTU PLANE

FROM ARTU

The swiss army knife of razor blade planes with six functions. No image found, but looks the same as the plane Lee Valley is selling.  According to the manufacturer, uses special ice hardened blades at a bed angle of 27 degrees.  Some discussion about it from the Hip Pocket  Aeronautics Builders Forum.

CONCLUSION

The promise of not having to sharpen or resharpen these razor blade planes may account for their continuing appeal, as does their simple, unthreatening and lightweight nature.  Most of the packaging emphasizes their easy multi-functionality, appealing to a home repair/ hobbyist crowd. In fact, the packaging is possibly as interesting as the planes are. Even though the general consensus among users is that they don’t work nearly as well as their advertised purposes, there have been many variations of these planes over the past 50+ years and several are still in production.

Although these planes barely function on most types of wood, they are much more functional in soft materials, including leather. The combination of their curved blade bed, very low effective blade angle, the off the shelf sharpness of razor blades and small sole area prevent excessive stretching of  leather that can occur with more standard block planes.There are also many types of small planes with normal blades: block planes, miniature planes, musical instrument planes and spokeshaves, toy planes, Stanley 12-101 trim plane, Lie-Neilson model makers plane and 102 block plane, Veritas Apron plane, etc…. None that I have tried work very well on leather, primarily, I think, due to inappropriate effective blade/ bed angles, excessive friction from the soles that causes the leather to stretch, buckle or tear, and clogging of the mouth.

I find razor blade planes interesting not so much because they are exemplars of the toolmakers art, but because they are emblematic of the post-WW2 home handyman boom, the creation of suburbia, 1950’s advertising and other societal aspects. The packaging also reflects a change in tool marketing from primarily a male activity, to a family one. Tool snobs may consider these types of planes closer to toys than tools – and they may be right – but they are all tiny pieces of the total picture that inform our understanding of tool use as a fundamental human activity.

Next week : Razor Blade Planes: Tips on Using Them to Pare Leather.

Paring In Action

I finally made a (very) short video showing edge paring using an English style A2 Cryo knife. Hopefully, early next year, in the new tool catalog, there will be videos of all the tools in action.  In the meantime, descriptions and images of tools are in the “TOOL CATALOG”  in the right hand column.

Video seems a promising technology for the preservation of craft based knowledge: it can clearly demonstrate and record hand skill techniques.  It can also be potentially misleading in terms of how easily a tool is used, and “special effects” are available on any computer.  But videos are popular, great for marketing, persuasive and hot right now.

Sit back, eat a piece of popcorn and enjoy the next 39 seconds.

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A    PEACHEY    KNIFE    IN    ACTION

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Observations on Blade Angles of English Style Leather Paring Knives

“One of the most admired skills in bookbinding is the paring of leather, yet only sharp tools and confidence are required.  Confidence is gained by experience, and sharp tools by a zelous consideration and care for knives.” Arthur Johnson, The Thames and Hudson Manuel of Bookbinding, p. 89

I would add that it is also critical to pay attention to the blade angle of the knife, since it affects how the knife cuts, the angle one holds the knife at, and consequently how the leather is cut.  I’ve found that roughly a 40-50 degree angle works best for edge paring.  First, a few terms defined.  The blade angle is from an imaginary line 90 degrees to the length of the blade.  I am calling a zero degree angle one that would be straight across where the dotted line is, pictured below would be roughly a 45 degree blade angle.  The bevel angle is the amount of slope on the bevel, in the case of leather paring knives usually around 13 degrees.  The diagram below is the style of knife a right handed binder would normally use. (1)

 

I’ve found there are two main issues that determine the optimal angle of the blade– how much the blade is skewed in use and how the knife is held.  The way I hold and use an English paring style knife is outlined below, as are the reasons why I consider a 40-50 degree blade angle ideal.  

Skewing the blade in use reduces the effective cutting angle, improving the initial cutting performance and not altering edge retention.  Although the more acute the bevel angle is the sharper the blade will be, if it is too severe the cutting edge will be very fragile and quickly deteriorate.  I haven’t figured out the math, but if the bevel angle is 13 degrees, I estimate an extreme skew reduces the effective cutting angle by a degree or two, which is significant.  

I tend to use an English style paring knife in three ways when I am edge paring- first to make a series of cuts using moderate skew, then a few finishing cuts using extreme skew, and finally use the knife with no skew, almost like a spokeshave, to smooth everything out. It doesn’t seem to make too much difference if you pare across the skin, as pictured above, or push the knife away from you.

To make a long, even bevel the angle of the knife held steady by my thumb and second finger on the other side of the the knife– they slide along the surface of the paring surface. In order to pare the leather evenly, the knife must be held at a consistent angle. (2) The angle the knife is held varies with the type of leather and skill of the binder- too high of an angle takes off virtually no leather, makes it more likely to slice through the flesh side of the skin and dulls the knife tip by digging into the paring surface.  Too low an angle makes the knife difficult to control, since most of the cutting edge is engaged into the leather.  Wide knives with long bevels exaggerate this problem.  Right handed beginning parers may want to use the forefinger of left hand to push the knife along the leather.  This allows one to concentrate on using the right hand to hold the knife at a consistent angle, as illustrated below.

One reason I dislike jigs for sharpening is that the hand skills to sharpen the knife are remarkable similar to the hand skills necessary to operate the knife– if you don’t have the hand skills to hold the knife at a consistant angle to sharpen it, you are not going to be able to hold it at a consistant angle to pare leather evenly.   Some like to pare across the leather, as illustrated below, and some like to pare up the side of the leather, starting the cut with the heel of the knife rather than the tip. Since lithographic stones are now extinct, I prefer paring on a piece of glass and saving stones for printers wishing to experience printing on a real stone.  There is no reason to pare on a litho stone other than tradition, and I suspect the only reason they were historically used is that they were a cheaper flat surface than glass, marble or granite

 

 

 

 

 

 

 

 

 

 

 

 

After a first cut is made, a second (and possibly third or fourth, depending on how long of a bevel is desired) is made by holding the knife at progressively  lower angles.  The depth of the cut can be judged by changes in the color of the leather or folding the leather in half, which doubles any errors.    If the leather is disturbed to check the progress, it is imperative that any stray bits be cleaned from under the skin, otherwise the knife will cut through these thicker layers.

As the leather becomes thinner, it becomes weaker, so I adopt the second knife position.  I skew the knife towards a more extreme angle and press down harder, which creates a lower effective bevel angle. This helps prevent tearing the leather.  It is much easier to take the leather off in long even strips with the first cuts, rather than try to correct mistakes later on.  If there are many irregularities, sometimes it is easier to use a spokeshave to even things out.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

After the edge is pared to the length and thinness desired, I rotate the knife into the third position, so that it is not skewed, and push it forward to even the previous cuts out.  This is almost more of a scraping action than a paring cut, and is meant to smooth out irregularities left from the previous cuts, not remove a lot of skin. The angle of the camera in the illustration seems to exaggerate angle that the knife is being held- in reality it is almost parallel to the skin. Again, a spokeshave could do this as well. The cutting edge of this knife is one inch, which is slightly larger than most turnins. Most of the time 7/8″ is a reasonable turn in width–compromising between giving a little extra room in case the leather is torn, and conserving leather.  One unintentional consequence of the acidic nature of some leathers is that they rapidly stain the pastedown, making it possible to observe in detail the pattern of trimming and size of turnins.  I admire the judgement (and frugality!) of some binders, capable of covering the book so economically that only a millimeter of two of leather extends under the pastedown in various places.

 

 

 

 

 

 

 

 

 

 

 

 

 

A roughly 45 degree angle seems to be the most comfortable in all three of the ways I hold the knife.  I have a set of knives that I use when teaching which consist of 22.5, 45, and 67.5 degrees, in order to compare what is most comfortable for each individual, and most opt for a roughly 45 degree angle. Another consideration is the angle of the wrist when using the knife– I’ve found around 40-50 to be most comfortable.  Keeping the angle of your wrist comfortable is important if you do a lot of production work, to avoid carpel tunnel syndrome.  Any numbness or tingling sensation is possibly a very serious problem, and medical attention should be sought.  Choosing a good quality knife, keeping it well stropped and sharp will also reduce the force needed to pare leather, reducing strain on the hand and wrist.  Finally, a 45 degree blade angle is much easier to sharpen than a 67.5 degree angle for two reasons– it is easier to get even pressure across the entire width of the bevel (especially the tip), and there is less metal to remove, so the sharpening is more rapid.  Paring leather is not difficult, as Johnson pointed out, it just takes some practice with a sharp knife, and an awareness of the blade angle.

 

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NOTES

1. As a left handed binder pointed out to me, simply changing the direction of paring allows a right hander to use a left handed knife, or vice versa.  Below I am comfortably using a left handed knife, holding the leather at the top and paring towards myself.  

 

2.  Some find it more comfortable to hold a knife with a handle.  In this case, it is sometimes necessary to hold the handle area of the knife off the paring surface in order to achieve a low angle.  This illustration also demonstrates side to side paring.