DW, I don't expect to try it, but just out of curiosity, how would you hollow ground a blade? It would seem impossible to do it on a flat sharpening stone...
I am disappointed to say my first attempts at sharpening my Tina and bevel point knives fell short, although I was grinding, per the Al Stohlman book instructions. Although they were both sharper after than before, I still found my Safety Beveler with the razor blade worked better. Particularly on chrome tanned leather, the Tina and bevel point knives tended to stretch the leather as I pull skived. The Safety Beveler was easier to get a good downward pressure on and didn't seem to stretch the leather.
I am thinking partly the knives aren't quite sharp enough. The sharpening stone instructions recommended a 23 degree angle, which maybe is too much? I also seemed to make a wider bevel at the ends of the blades than the middle, and am not sure how to avoid this.
Jenny
Tools of the Trade
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jenny_fleishman
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dw
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Re: Tools of the Trade
Jenny,
If the leather is stretching as you try to skive it, it's a gross (meaning obvious) sign of dullness and/or the roughness (striations) on the blade. The only reason the leather would stretch is that both the edge and the surface are "dragging"--too much friction.
Learning to sharpen properly is not a one-two, snap your fingers skill. That's exactly why people invented and now rely upon the safety skivers--no need to learn or go through all the hassles and frustrations of gaining proficiency. Don't throw away your safety skiver, especially if you need to finish a job, but you'll be forever crippled, in my opinion, as a shoe/bootmaker if you never learn to sharpen. The principles involved, the understandings that evolve are essential for all aspects of shoemaking. Sure, you can swap out an exacto blade for a decent clicker knife, substitute a safety skiver for a Tina, but what's the substitute for a sharp awl? Or a sharp Bell knife? How do you sharpen your splitter blade if you don't understand sharpening?
Hollow grinding needs to be done with infinite care and on a grinder of some sort. Or, actually I touched up the hollow grind on one of my Berg knives on the "B" wheel of my finisher this morning. The advantage there is that you can see exactly where the sandpaper is cutting if only by virtue of seeing where the sparks are originating.
No matter what you do, understand that sharpening a new knife takes a great deal of time just to "rough out" the initial shape. Get the bevel or hollow grind just right. And after all that, once that shape is attained, you're gonna be extra careful to maintain that shape in the final honing process.
As far as where the sharpening is happening on the edge of the blade --middle or tip--it's a lot like dancing...there's a lot going on there all at the same time. You've not only got the push or the draw movement to contend with but you got to control angle (that's obvious) as well as "sweep." So that if you have a curved blade, tip to heel, you have to lift or lower the hand to match that curve.
And sometimes if the blade is flat and you find yourself sharpening at the extremes--tip, heel or belly--it just indicates you need to shape the bevel a little more evenly.
Tight Stitches
DWFII--Member HCC
If the leather is stretching as you try to skive it, it's a gross (meaning obvious) sign of dullness and/or the roughness (striations) on the blade. The only reason the leather would stretch is that both the edge and the surface are "dragging"--too much friction.
Learning to sharpen properly is not a one-two, snap your fingers skill. That's exactly why people invented and now rely upon the safety skivers--no need to learn or go through all the hassles and frustrations of gaining proficiency. Don't throw away your safety skiver, especially if you need to finish a job, but you'll be forever crippled, in my opinion, as a shoe/bootmaker if you never learn to sharpen. The principles involved, the understandings that evolve are essential for all aspects of shoemaking. Sure, you can swap out an exacto blade for a decent clicker knife, substitute a safety skiver for a Tina, but what's the substitute for a sharp awl? Or a sharp Bell knife? How do you sharpen your splitter blade if you don't understand sharpening?
Hollow grinding needs to be done with infinite care and on a grinder of some sort. Or, actually I touched up the hollow grind on one of my Berg knives on the "B" wheel of my finisher this morning. The advantage there is that you can see exactly where the sandpaper is cutting if only by virtue of seeing where the sparks are originating.
No matter what you do, understand that sharpening a new knife takes a great deal of time just to "rough out" the initial shape. Get the bevel or hollow grind just right. And after all that, once that shape is attained, you're gonna be extra careful to maintain that shape in the final honing process.
As far as where the sharpening is happening on the edge of the blade --middle or tip--it's a lot like dancing...there's a lot going on there all at the same time. You've not only got the push or the draw movement to contend with but you got to control angle (that's obvious) as well as "sweep." So that if you have a curved blade, tip to heel, you have to lift or lower the hand to match that curve.
And sometimes if the blade is flat and you find yourself sharpening at the extremes--tip, heel or belly--it just indicates you need to shape the bevel a little more evenly.
Tight Stitches
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Re: Tools of the Trade
If you all will forgive me I'm gonna put on my "official" hat for a moment to make an observation...
Thinking about David's comments...that's why we do this on a forum. It's a natural tendency, I guess, for some folks to want to confine questions to private email (and some...even some "experts"...would rather answer privately) or, perhaps out of shyness, never ask at all. But if Jenny hadn't asked these questions on the forum she would be the only one getting anything out of the answers. And there never would have been a discussion with various people contributing and a number of different methods being outlined. Even someone who is well versed in a subject learns something in such varied discussions. The forum was deliberately designed to present and record techniques and skills for a much wider audience than the people immediately contributing.
Believe it or not, most of us feel really good when we can help. There's all kinds of selfish reasons for doing so...you don't need to be promoting yourself or your products to make it worth your while. If nothing else, just articulating a concept for someone else helps you understand it better yourself. "The teacher learns twice."
Emmett
Thinking about David's comments...that's why we do this on a forum. It's a natural tendency, I guess, for some folks to want to confine questions to private email (and some...even some "experts"...would rather answer privately) or, perhaps out of shyness, never ask at all. But if Jenny hadn't asked these questions on the forum she would be the only one getting anything out of the answers. And there never would have been a discussion with various people contributing and a number of different methods being outlined. Even someone who is well versed in a subject learns something in such varied discussions. The forum was deliberately designed to present and record techniques and skills for a much wider audience than the people immediately contributing.
Believe it or not, most of us feel really good when we can help. There's all kinds of selfish reasons for doing so...you don't need to be promoting yourself or your products to make it worth your while. If nothing else, just articulating a concept for someone else helps you understand it better yourself. "The teacher learns twice."
Emmett
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jenny_fleishman
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Re: Tools of the Trade
Thanks, DW and all, for answering my endless questions! You're encouraging me (not that I need it 
) with your above comments, so here are a few more questions...
Is the Osborne head knife a good quality knife? Siegel has it on sale right now.
How do you sharpen the curved blade of the head knife and maintain that curved edge without moving the blade across the stone in a sweep almost parallel to the edge of the blade (which would not be the direction the blade would move when skiving). it would seem the grooves on the blade would not be in an optimum direction.
Also, is there a reason why sharpening stones are so narrow (other than economy)? With the longer knives, it seems you have to sweep in a curve to get the whole blade on the stone.
What do you do when your stone loses its flat surface (get a new stone?), or is there a way to maintain the flatness all along, or restore it?
In the Wilson Gracey tape, the shoemaker had an oval shape sharpening stone, and would frequently swipe his knife over it while skiving to keep it sharp. Does anyone do anything like that?
Jenny
) with your above comments, so here are a few more questions... Is the Osborne head knife a good quality knife? Siegel has it on sale right now.
How do you sharpen the curved blade of the head knife and maintain that curved edge without moving the blade across the stone in a sweep almost parallel to the edge of the blade (which would not be the direction the blade would move when skiving). it would seem the grooves on the blade would not be in an optimum direction.
Also, is there a reason why sharpening stones are so narrow (other than economy)? With the longer knives, it seems you have to sweep in a curve to get the whole blade on the stone.
What do you do when your stone loses its flat surface (get a new stone?), or is there a way to maintain the flatness all along, or restore it?
In the Wilson Gracey tape, the shoemaker had an oval shape sharpening stone, and would frequently swipe his knife over it while skiving to keep it sharp. Does anyone do anything like that?
Jenny
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dw
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Re: Tools of the Trade
Jenny,
I can't comment on the Osbourne round or head knives. I own a couple of antiques but I don't use them. I have a small custom-made head knife but after I have shaped the blade, I tend to sharpen it on my RazorSharp system so the grit on the wheel is always moving off the edge...more or less perpendicular to the edge. Beyond that, well, again I don't use them much so someone like David would probably be better able to give you some guidance. Still...thinking about it, I still think determining how you are going to use the blade and sharpening with the same motion is the key...even if you have to sharpen differently on the different sides of a round knife
As far as re-surfacing a stone, I know it can be done but I've never needed to, in almost 35 years of using my stones. I think sharpening in a sweep rather than a circular motion and buying good quality stones in the first place may go a long way towards addressing this problem.
Tight Stitches
DWFII--Member HCC
I can't comment on the Osbourne round or head knives. I own a couple of antiques but I don't use them. I have a small custom-made head knife but after I have shaped the blade, I tend to sharpen it on my RazorSharp system so the grit on the wheel is always moving off the edge...more or less perpendicular to the edge. Beyond that, well, again I don't use them much so someone like David would probably be better able to give you some guidance. Still...thinking about it, I still think determining how you are going to use the blade and sharpening with the same motion is the key...even if you have to sharpen differently on the different sides of a round knife
As far as re-surfacing a stone, I know it can be done but I've never needed to, in almost 35 years of using my stones. I think sharpening in a sweep rather than a circular motion and buying good quality stones in the first place may go a long way towards addressing this problem.
Tight Stitches
DWFII--Member HCC
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tomo
Re: Tools of the Trade
Some more grist guys.
Stones can be 'dressed' by wetting two stones and rubbing together ie face to face; every now and then just rinse them under a bit of running water.
To sharpen a round knife you can either start at at one point and move in little circles rolling your hand as you go, so that the sharpening point moves across the knife to the other point, then do the same movement back to the start point. This method is in contrast to DW's thoughts on direction of travel - which are correct, however a round knife is used for a multitude of cutting techniques, and if it's sharp and stropped properly, then the drag effect is inconsequential.
Another way is to cross the stone in a big figure eight but without performing the little circles as in the method above. Again you need to tip your hand so that the precise point you want to sharpen is in contact with the stone.
You can go quite fast when sharpening with either method but it's probably best to start slow until you develop muscle memory.
Also, use some dishwash liquid or detergent in a little water to facilitate sharpening. Don't use oil. Oil is designed to REDUCE friction which is not what you want. The detergent will help keep the stone clean too.
The rule is 'The harder the steel, the softer the stone.' A soft stone wears(out) faster, but at an up close and personal level the stone is always presenting new facets to the face of the steel thus maximising the abrasive effect.
With a soft stone you can feel the 'softness,' it makes like a susshing soft sound when you use it. Whereas a hard stone has a 'tinnie' sound and feel.
More power to y'awl
T.
Stones can be 'dressed' by wetting two stones and rubbing together ie face to face; every now and then just rinse them under a bit of running water.
To sharpen a round knife you can either start at at one point and move in little circles rolling your hand as you go, so that the sharpening point moves across the knife to the other point, then do the same movement back to the start point. This method is in contrast to DW's thoughts on direction of travel - which are correct, however a round knife is used for a multitude of cutting techniques, and if it's sharp and stropped properly, then the drag effect is inconsequential.
Another way is to cross the stone in a big figure eight but without performing the little circles as in the method above. Again you need to tip your hand so that the precise point you want to sharpen is in contact with the stone.
You can go quite fast when sharpening with either method but it's probably best to start slow until you develop muscle memory.
Also, use some dishwash liquid or detergent in a little water to facilitate sharpening. Don't use oil. Oil is designed to REDUCE friction which is not what you want. The detergent will help keep the stone clean too.
The rule is 'The harder the steel, the softer the stone.' A soft stone wears(out) faster, but at an up close and personal level the stone is always presenting new facets to the face of the steel thus maximising the abrasive effect.
With a soft stone you can feel the 'softness,' it makes like a susshing soft sound when you use it. Whereas a hard stone has a 'tinnie' sound and feel.
More power to y'awl
T.
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jenny_fleishman
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Re: Tools of the Trade
Tom, are you saying to use dishwashing soap instead of oil for sharpening ALL tools, or just the round knife?
My 3 different grit stones are mounted to a triangular piece of wood, might be hard to rinse off without dousing the wood...
Jenny
My 3 different grit stones are mounted to a triangular piece of wood, might be hard to rinse off without dousing the wood...
Jenny
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shoestring
Re: Tools of the Trade
Since the thread is on sharpening & skiving.Has anyone ever made a skiver from an old hack saw blade.And reading this wealth of information lets me know that I am able to keep my knives nice and sharp.Besides I have several that an old shoe repairman gave me he did the hard work my job was to keep them workable.AS for head knives I made out pretty good getting some off of ebay.
Ed
Ed
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daniel
Re: Tools of the Trade
D.W.,
Could you favor us with your technique for sharpening the Frommer version of the Ron's French Edgers?
Mine are not as sharp as they could be, I'm sure.
Dan
Could you favor us with your technique for sharpening the Frommer version of the Ron's French Edgers?
Mine are not as sharp as they could be, I'm sure.
Dan
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dw
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Re: Tools of the Trade
Dan,
Well, the "Frommer" version of Ron's edger is sharpened from the bottom...which I understand is a deviation from traditional and historical French edgers. Practically speaking, the top of the "blade" must be cut/machined smooth and extremely even or such bottom sharpening will only leave a ragged edge. Again, that's a deviation from older French edgers...at least the one's that have come into my hands.
I asked Ron to make these for me to use specifically in bootmaking rather than the more common usage primarily in saddle and harness making. They also tend to have both thinner and shallower guard-rails. I have a full set of these terrific tools. They are both beautiful and quality...and exactly what I wanted.
So...to sharpen them I simply push (that's the direction I will use them) across a soft Arkansas stone, trying to keep a consistent angle and an even pressure crosswise. When I work up a little burr on the upper surface, I hone them further on a black Arkansas and then I strop the upper surface with a tripoli or rouge loaded piece of soling leather. I never, ever, sharpen the top surface of the blade and I studiously try to keep the upper surface of the blade flat against the sole leather strop so that I am not inadvertently rounding the edge. I will also strop the bottom edge ...switching back and forth until any "wire" is removed. No secondary bevels anywhere...the bevel on the bottom edge is as long as it can be...generally preserving the profile of the tool as it comes from Ron's Tools.
Hope that helps...
PS...any relation to Ed?
Tight Stitches
DWFII--Member HCC
Well, the "Frommer" version of Ron's edger is sharpened from the bottom...which I understand is a deviation from traditional and historical French edgers. Practically speaking, the top of the "blade" must be cut/machined smooth and extremely even or such bottom sharpening will only leave a ragged edge. Again, that's a deviation from older French edgers...at least the one's that have come into my hands.
I asked Ron to make these for me to use specifically in bootmaking rather than the more common usage primarily in saddle and harness making. They also tend to have both thinner and shallower guard-rails. I have a full set of these terrific tools. They are both beautiful and quality...and exactly what I wanted.
So...to sharpen them I simply push (that's the direction I will use them) across a soft Arkansas stone, trying to keep a consistent angle and an even pressure crosswise. When I work up a little burr on the upper surface, I hone them further on a black Arkansas and then I strop the upper surface with a tripoli or rouge loaded piece of soling leather. I never, ever, sharpen the top surface of the blade and I studiously try to keep the upper surface of the blade flat against the sole leather strop so that I am not inadvertently rounding the edge. I will also strop the bottom edge ...switching back and forth until any "wire" is removed. No secondary bevels anywhere...the bevel on the bottom edge is as long as it can be...generally preserving the profile of the tool as it comes from Ron's Tools.
Hope that helps...
PS...any relation to Ed?
Tight Stitches
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dw
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Re: Tools of the Trade
Tom,
That's a good trick with the detergent and it makes perfect sense...although I've never heard of it before. I'd always heard that the oil was more to keep the abraded metal from clogging the stone--I've seen old stones that looked like there was a vein of steel running through it. You couldn't easily remove or dislodge the steel, either. I think the soap would work well...although come to think of it, soap is just fat and lye, and detergent must be, at least functionally if not chemically, similar.
But the best "cran" I've heard in a long time is the one of dressing a stone using another stone. That sounds like an oldie but I never ran across it before.
Gotta love the CC! thank you!
Tight Stitches
DWFII--Member HCC
That's a good trick with the detergent and it makes perfect sense...although I've never heard of it before. I'd always heard that the oil was more to keep the abraded metal from clogging the stone--I've seen old stones that looked like there was a vein of steel running through it. You couldn't easily remove or dislodge the steel, either. I think the soap would work well...although come to think of it, soap is just fat and lye, and detergent must be, at least functionally if not chemically, similar.
But the best "cran" I've heard in a long time is the one of dressing a stone using another stone. That sounds like an oldie but I never ran across it before.
Gotta love the CC! thank you!
Tight Stitches
DWFII--Member HCC
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jenny_fleishman
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Re: Tools of the Trade
DW, resharpened my Tina knife and bevel edge knife tonight, and believe I got them sharper. The Tina knife passed the fingernail test, anyway, however it's still stretching the chrome tanned leather when I use it.
It occurs to me that my skiving technique (with the Tina knife) may be incorrect...the way I hold the knife in my hand (I'm right-handed, and pull skiving), the edge of the strip of leather to work on (right side or left side?), and the angle of the knife to the edge of the leather (not how flat it is to the leather, but the angle you see looking down at the work from above). If it's not too much to ask, could you post a photo of the process that would show these things?....sigh...I keep figuring out there're more things I don't know! Thanks.
Jenny
It occurs to me that my skiving technique (with the Tina knife) may be incorrect...the way I hold the knife in my hand (I'm right-handed, and pull skiving), the edge of the strip of leather to work on (right side or left side?), and the angle of the knife to the edge of the leather (not how flat it is to the leather, but the angle you see looking down at the work from above). If it's not too much to ask, could you post a photo of the process that would show these things?....sigh...I keep figuring out there're more things I don't know! Thanks.
Jenny
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tomo
Re: Tools of the Trade
Jenny, DW, Ed,
I put say 1/4 cup detergent in a squirt bottle, squirt bottle's better than a spray, and squirt say a tablespoonful more or less on the stone as needed. I use this on all my stones.
Most stones here turn up in wooden boxes that some ol' boy or handyman has made, and usually have a couple of brads sticking out the bottom of the box about an 1/8" so it grips on the bench and you're not chasing it around, but one of these will rark your table top up no end. Don't worry about the wood getting wet as it's not perminant and most wood's treated.
Ed you could use a machine(?) hacksaw blade but it won't hold an edge ie it's too soft. You could temper it then try. Grind it to the shape you want, then heat it back from the cutting edge until the heat travels out to the edge so that the steel is dull cherry red, then stick it in oil for a few seconds - say 5, then remove it and try polishing the edge with fine emery cloth so that it's clean, not forgetting that it'll still be hot. Then gently warm the blade back up so that the colour travels up to the cutting edge. When the cutting edge turns brown/purple quench it again. This is a simplification and it'll largely be trial and error. If you quench the blade in water straight off it'll be too brittle, and even dropping it on a concrete floor will break it. The oil will smoke a bit when you harpoon it with the blade, but don't worry about that ( unless your smoke alarm's going off
)
DW you're right about the lye and tellow along with caustic soda being used in soap but detergent is a different animal (it goes through a process called Sulphurnation(sp?) that's why they sell the fact that it cuts through grease and gets your dishes squeeky clean.
You're getting me seriously interested in those edgers of Ron's too BTW.
More power to y'awls.
T.
I put say 1/4 cup detergent in a squirt bottle, squirt bottle's better than a spray, and squirt say a tablespoonful more or less on the stone as needed. I use this on all my stones.
Most stones here turn up in wooden boxes that some ol' boy or handyman has made, and usually have a couple of brads sticking out the bottom of the box about an 1/8" so it grips on the bench and you're not chasing it around, but one of these will rark your table top up no end. Don't worry about the wood getting wet as it's not perminant and most wood's treated.
Ed you could use a machine(?) hacksaw blade but it won't hold an edge ie it's too soft. You could temper it then try. Grind it to the shape you want, then heat it back from the cutting edge until the heat travels out to the edge so that the steel is dull cherry red, then stick it in oil for a few seconds - say 5, then remove it and try polishing the edge with fine emery cloth so that it's clean, not forgetting that it'll still be hot. Then gently warm the blade back up so that the colour travels up to the cutting edge. When the cutting edge turns brown/purple quench it again. This is a simplification and it'll largely be trial and error. If you quench the blade in water straight off it'll be too brittle, and even dropping it on a concrete floor will break it. The oil will smoke a bit when you harpoon it with the blade, but don't worry about that ( unless your smoke alarm's going off
) DW you're right about the lye and tellow along with caustic soda being used in soap but detergent is a different animal (it goes through a process called Sulphurnation(sp?) that's why they sell the fact that it cuts through grease and gets your dishes squeeky clean.
You're getting me seriously interested in those edgers of Ron's too BTW.
More power to y'awls.
T.
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tomo
Re: Tools of the Trade
I test for sharpness by shaving the hair on my forearm. I hold the knife at right angles to my arm and the cutting edge about 70-80o to the surface of my arm (hope that's clear) ie tip the back of the knife back towards your elbow a 1/2" or so, then just move the blade down your arm, but cripes, whatever you do don't use a slicing motion, just scrape the blade down your arm. If it's sharp hairs will pop off straight away, if the edge is dull they won't. You can test in several places along the blade to get a better idea.
DW's fingernail trick works good, but the feeling of the blade on my nail just leaves me cold.
More power to y'awl.
T.
DW's fingernail trick works good, but the feeling of the blade on my nail just leaves me cold.
More power to y'awl.
T.
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erickgeer
Re: Tools of the Trade
Jenny,
What kind of leather did you decide on? Earlier you were talking about some skins that sounded like garment leathers. If this is what you are using, then the skiving blade needs to be extra sharp, and will require more frequent sharpening.
Has anyone else had this experience?
Erick
What kind of leather did you decide on? Earlier you were talking about some skins that sounded like garment leathers. If this is what you are using, then the skiving blade needs to be extra sharp, and will require more frequent sharpening.
Has anyone else had this experience?
Erick
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jenny_fleishman
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Re: Tools of the Trade
Erick, the leather I am using for my fitter shoe is approx. 5 oz. chap leather.
Jenny
Jenny
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dw
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Re: Tools of the Trade
Jenny,
Well, I've scoured my hard drive and only have a couple of pics of skiving (it's hard to hold a camera when two out of four hands are engaged in skiving)...both just happen to be from the current book I am writing. That said, I'm not sure the photo below will help you any. I skive pushing and from what you've said, you are pull skiving. But for what it's worth, I've posted it.
But when I think about it, I can only come up with a couple of reasons that your leather would be stretching:
(A) the knife is not sharp....or sharp enough. Again...this isn't something where "good enough" is good enough. Sharpening is a very precise process of stiff wrists and consistent angles. Any secondary bevels and you increase resistance going through the leather.
(B) The leather is stretchy, gritty crap. (pardon me). Chrome tan leather, of poor quality especially, is notorious for having residual chrome salt in the leather. That alone will dull a knife and the sharper the knife the more quickly it will dull up.
Having said all that, one of the reasons I do not pull skive is that I don't think the leather is as easily supported when you are using your *right* hand to pull a knife along the *left* edge of a piece of leather. Where does the left hand--the supporting hand--go? Crossed over the top of the knife and right hand to support the leather on the right side of the knife??! Awkward as hellgrammites...for me at least. And if the leather is not supported fairly close to the edge being skived, any propensity to stretch will be just that much abetted.
With regard to the photo, the angle of the blade is a little misleading--it was a "staged" shot--the tip of the blade could be just a hair more towards the edge of the leather. But the really important point is that the knife needs to be used in a slicing motion. It is not a chisel. If you get the blade embedded in the leather and just push, you forfeit the edge, so to speak. The blade must enter the leather close to (not at) the tip and slide down the edge to the heel of the blade and then, without removing the blade from the leather the edge is withdrawn so that it is cutting more towards the tip again...at which point the whole process is repeated--a slicing motion that ends up at the heel of the blade. This is a gross over simplification but I offer it to draw the distinction between slicing and chiseling. Done correctly, you really can't see any distinct slicing or "sawing" of the blade but the slicing concept is definitely at the heart of good hand skiving. And to further illustrate the point...that's why the knife on the bell skiver rotates.
hollow ground Berg "fish" skiving knife on glass skiving dome
Tight Stitches
DWFII--Member HCC
(Message edited by dw on April 18, 2006)
Well, I've scoured my hard drive and only have a couple of pics of skiving (it's hard to hold a camera when two out of four hands are engaged in skiving)...both just happen to be from the current book I am writing. That said, I'm not sure the photo below will help you any. I skive pushing and from what you've said, you are pull skiving. But for what it's worth, I've posted it.
But when I think about it, I can only come up with a couple of reasons that your leather would be stretching:
(A) the knife is not sharp....or sharp enough. Again...this isn't something where "good enough" is good enough. Sharpening is a very precise process of stiff wrists and consistent angles. Any secondary bevels and you increase resistance going through the leather.
(B) The leather is stretchy, gritty crap. (pardon me). Chrome tan leather, of poor quality especially, is notorious for having residual chrome salt in the leather. That alone will dull a knife and the sharper the knife the more quickly it will dull up.
Having said all that, one of the reasons I do not pull skive is that I don't think the leather is as easily supported when you are using your *right* hand to pull a knife along the *left* edge of a piece of leather. Where does the left hand--the supporting hand--go? Crossed over the top of the knife and right hand to support the leather on the right side of the knife??! Awkward as hellgrammites...for me at least. And if the leather is not supported fairly close to the edge being skived, any propensity to stretch will be just that much abetted.
With regard to the photo, the angle of the blade is a little misleading--it was a "staged" shot--the tip of the blade could be just a hair more towards the edge of the leather. But the really important point is that the knife needs to be used in a slicing motion. It is not a chisel. If you get the blade embedded in the leather and just push, you forfeit the edge, so to speak. The blade must enter the leather close to (not at) the tip and slide down the edge to the heel of the blade and then, without removing the blade from the leather the edge is withdrawn so that it is cutting more towards the tip again...at which point the whole process is repeated--a slicing motion that ends up at the heel of the blade. This is a gross over simplification but I offer it to draw the distinction between slicing and chiseling. Done correctly, you really can't see any distinct slicing or "sawing" of the blade but the slicing concept is definitely at the heart of good hand skiving. And to further illustrate the point...that's why the knife on the bell skiver rotates.
hollow ground Berg "fish" skiving knife on glass skiving dome
Tight Stitches
DWFII--Member HCC
(Message edited by dw on April 18, 2006)
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dw
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Re: Tools of the Trade
Jenny,
PS...ordinarily, the fingers of my left hand would be splayed just this side of the knife and along the edge to support the leather.
Erick,
Yes, indeed, and truth to tell chap leather is probably not ever going to be the same quality as shoe leather. It generally lacks firmness and is made of marginal hides to begin with. My old saddlemaking master used to use blue hides for chaps.
Tight Stitches
DWFII--Member HCC
(Message edited by dw on April 18, 2006)
PS...ordinarily, the fingers of my left hand would be splayed just this side of the knife and along the edge to support the leather.
Erick,
Yes, indeed, and truth to tell chap leather is probably not ever going to be the same quality as shoe leather. It generally lacks firmness and is made of marginal hides to begin with. My old saddlemaking master used to use blue hides for chaps.
Tight Stitches
DWFII--Member HCC
(Message edited by dw on April 18, 2006)
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jenny_fleishman
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Re: Tools of the Trade
Well, I can tell you already that I was holding my knife completely differently--pull skiving along the left edge with the knife pointing NW (if on a map) and the point of the knife off the edge of the leather. I actually tried to do a drawing last night of how I was holding the knife, but it was too awful to post! Actually, I thought the drawing was awful, but it's looking like my technique was even more awful than the drawing!
DW, you described push skiving. At the moment I don't have the proper knife to try that. Still not sure what the proper way is to pull skive...Should the knife be parallel to the edge of the leather as in the picture you posted, but pointed towards your body (wince)? Heel towards the edge of the leather?
I'm looking at the following knife, wondering if it would be versatile, because of the symmetrical curve of the blade, for both push and pull skiving. The edge of the blade would not be nearly as angled as the Tina knives, however. Anyone have experience with or opinions on this style of knife?
https://www.siegelofca.com/itemdetail.asp?prodid=256
Thanks,
Jenny
DW, you described push skiving. At the moment I don't have the proper knife to try that. Still not sure what the proper way is to pull skive...Should the knife be parallel to the edge of the leather as in the picture you posted, but pointed towards your body (wince)? Heel towards the edge of the leather?
I'm looking at the following knife, wondering if it would be versatile, because of the symmetrical curve of the blade, for both push and pull skiving. The edge of the blade would not be nearly as angled as the Tina knives, however. Anyone have experience with or opinions on this style of knife?
https://www.siegelofca.com/itemdetail.asp?prodid=256
Thanks,
Jenny
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dw
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Re: Tools of the Trade
Jenny,
If I were gonna pull skive (and remember this is not my preferred method) this is what it would look like:
I wouldn't mind having the knife you link to, but I wouldn't use it for skiving.
Tight Stitches
DWFII--Member HCC
If I were gonna pull skive (and remember this is not my preferred method) this is what it would look like:
I wouldn't mind having the knife you link to, but I wouldn't use it for skiving.
Tight Stitches
DWFII--Member HCC
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jenny_fleishman
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Re: Tools of the Trade
DW, what would you use that knife for?
After seeing your last post, I might have been skiving correctly, after all. Maybe the knife just isn't sharp enough. I might get one of those Razor Sharp systems you recommend...
Jenny
After seeing your last post, I might have been skiving correctly, after all. Maybe the knife just isn't sharp enough. I might get one of those Razor Sharp systems you recommend...
Jenny
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tomo
Re: Tools of the Trade
Morning DW,
Do you usually wear cuffs while you're working?
Good explanation BTW.
More power to y'awl.
T.
Do you usually wear cuffs while you're working?
Good explanation BTW.
More power to y'awl.
T.
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dw
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Re: Tools of the Trade
Tom,
I do wear cuffs. Not out and about but when working, for sure. It protects the sleeves of my shirts and I get about 2 years longer wear out of them than before I started wearing cuffs. 'Sides, I made 'em and I can't just put them in a glass cabinet.
I wear an apron, too.
Morning!? Heck, it must be Wednesday already.
Tight Stitches
DWFII--Member HCC
I do wear cuffs. Not out and about but when working, for sure. It protects the sleeves of my shirts and I get about 2 years longer wear out of them than before I started wearing cuffs. 'Sides, I made 'em and I can't just put them in a glass cabinet.
I wear an apron, too. Morning!? Heck, it must be Wednesday already.
Tight Stitches
DWFII--Member HCC
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dmcharg
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Re: Tools of the Trade
Jenny,
Sorry the pictures of the skiving knife are taking a while to get up on the forum. I discovered that the local community internet center hasn't got the capabilities so I've got to manage it some other way . I want to work this out
Cheers
Duncan
Sorry the pictures of the skiving knife are taking a while to get up on the forum. I discovered that the local community internet center hasn't got the capabilities so I've got to manage it some other way . I want to work this out
Cheers
Duncan