IF I "hone" the blade with a diamond pasted strop - in which direction should I hone?

[dobka]

Hi, I was wondering - IF I "hone" the blade with a diamond pasted strop - in which direction should I hone? The same way as you hone with a hone (blade goes forward) or the way you strop the blade (the spine goes forward)?

Also, please tell me on what surfaces shoud I use a diamond paste - maybe I coud put it on glass surface (or wood) instead of leather strop? Anyone any experience or knowledge?

Thanks, guys!

 

[jkh]

It is a strop, so you use a stropping stroke (edge trailing).

Most folks like diamond spray on hard pressed wool.

 

[ouch]

Stropping always involves the edge facing away from the direction of motion, otherwise you'll ruin both your edge and your strop.

 

[dobka]

It is a strop, so you use a stropping stroke (edge trailing).

Most folks like diamond spray on hard pressed wool.

Ok, and If use diamond spray on hard pressed wool how do I hone then? The same way as on the strop?

 

[dobka]

OOOPS, sorry, I read "hard pressed wood", not hard pressed wool I got the idea.
Yesterday I read some carpenters forum they were discussing about putting the diamond paste on some type of wood, that's why I'm asking... Anyone knows anything about this?

 

[ouch]

You're probably thinking of balsa.

 

[dobka]

You're probably thinking of balsa.

Yes, balsa. How do you hone on that materrial?

 

[michiganlover]

Yes, balsa. How do you hone on that materrial?

Same as with a typical strop, spine first, with the edge tailing.

Trying to lead with the edge would cause the edge to dig into the soft balsa, thereby dulling the living daylights out of it.

 

[Fairlight]

It's always safe to hone/strop a blade edge trailing. On hones which can be used edge leading, it just reduces burr formation to do so. The worst thing that will ever happen if you always sharpen edge trailing is you'll have to do a little more work to get rid of a wire edge. Of course, if you sharpen edge leading on a strop or soft hone, you can (WILL for a strop) damage both the blade and the sharpening tool.

I know lots of people who say you shouldn't use a waterstone edge leading because the particles on the surface of the stone will ding up the edge.

Caveat: My experience is with sharpening knives, not razors.

 

[dobka]

It's always safe to hone/strop a blade edge trailing. On hones which can be used edge leading, it just reduces burr formation to do so. The worst thing that will ever happen if you always sharpen edge trailing is you'll have to do a little more work to get rid of a wire edge. Of course, if you sharpen edge leading on a strop or soft hone, you can (WILL for a strop) damage both the blade and the sharpening tool.

I know lots of people who say you shouldn't use a waterstone edge leading because the particles on the surface of the stone will ding up the edge.

Caveat: My experience is with sharpening knives, not razors.

So can I understand clear - there is no necessity to sharpen you blade edge leading even if you have a fancy waterstone?! All the videos I saw proclaimed that you have to sharpen your tools (when using a hone) edge leading. Although nobody told that you cannot hone the blade edge trailing way...

 

[LaughingAtFate]

I know lots of people who say you shouldn't use a waterstone edge leading because the particles on the surface of the stone will ding up the edge.

That sort of comment always makes me laugh, if one removed the swarf and cleaned the stone on a regular basis (ie, just before you honed) the particles would never be a problem with the edge

 

[jkh]

So can I understand clear - there is no necessity to sharpen you blade edge leading even if you have a fancy waterstone?! All the videos I saw proclaimed that you have to sharpen your tools (when using a hone) edge leading. Although nobody told that you cannot hone the blade edge trailing way...

Just because you can do something doesn't mean you should. I think the bigger point was: if you strop (hanging leather, leather on wood, balsa wood, hanging hard pressed wool, etc) with the edge leading you will ruin your edge and most likely the strop as well. If you happen to hone with the spine leading you aren't going to wreck your straight or hone; however, you really should be honing with the edge leading.

Keep it simple - hone with edge leading and strop with spine leading.

 

[Fairlight]

That sort of comment always makes me laugh, if one removed the swarf and cleaned the stone on a regular basis (ie, just before you honed) the particles would never be a problem with the edge

Waterstones abrade during use. It's not just particles of metal from the blade but from the stone as well. This is actually a positive feature, if you go longer without flushing the stone effectively becomes a higher grit. I haven't noticed this particular dulling phenomenon, but I *HAVE* noticed that on my 4000x specifically (I don't own anything finer ATM) edge leading tends to lead to gouging of the stone, which is certainly not a good thing.

Keep it simple - hone with edge leading and strop with spine leading.

Wouldn't keeping it simple be doing it the same way every time? I can't see what disadvantage there would really be from honing a straight edge trailing... you're going to strop it anyway, which will remove burrs. The size of a wire edge shrinks with increasing grit also... If you're going to 8000x or higher it's not that much of a concern. It's more of an issue if you are starting with higher grits, such as if you were restoring a particularly dull (or chipped, etc) blade.

Has anyone here ever actually had trouble with a wire edge on their straight, where it seems sharp at first but then dulls very quickly? It seems to me like the degree of polish applied to these blades would preclude a wire edge left at the end.

 

[jkh]

Wouldn't keeping it simple be doing it the same way every time? I can't see what disadvantage there would really be from honing a straight edge trailing... you're going to strop it anyway, which will remove burrs. The size of a wire edge shrinks with increasing grit also... If you're going to 8000x or higher it's not that much of a concern. It's more of an issue if you are starting with higher grits, such as if you were restoring a particularly dull (or chipped, etc) blade.

Has anyone here ever actually had trouble with a wire edge on their straight, where it seems sharp at first but then dulls very quickly? It seems to me like the degree of polish applied to these blades would preclude a wire edge left at the end.

I guess keeping it simple would be doing what the overwhelming majority of people are doing, including what honers that have been doing it for centuries - honing straight razors with the edge leading.

It is my understanding that that goal with honing a straight razor is never have a burr form in the first place. I'd be interested to hear a honemeister chime in on the topic, since I am by no means an expert.

 

[Bart]

Wouldn't keeping it simple be doing it the same way every time? I can't see what disadvantage there would really be from honing a straight edge trailing... you're going to strop it anyway, which will remove burrs. The size of a wire edge shrinks with increasing grit also... If you're going to 8000x or higher it's not that much of a concern. It's more of an issue if you are starting with higher grits, such as if you were restoring a particularly dull (or chipped, etc) blade.

Has anyone here ever actually had trouble with a wire edge on their straight, where it seems sharp at first but then dulls very quickly? It seems to me like the degree of polish applied to these blades would preclude a wire edge left at the end.

Wire edges, burrs, or whatever we want to call them, have little do to with razor sharpening. At least, not in the sense it is used in knife and tool sharpening. On a razor you don't want to hone till a burr folds over, and next remove it with a strop. This will simply not leave an edge keen enough for a comfortable shave. With a kitchen knife, chisel, plane blade or most other cutting tools we don't care. It's great to shave an few arm hairs with a freshly sharpened wood chisel, but soon after the first wood has been severed by that edge, it already lost that kind of keenness. That's OK. The purpose of the tool doesn't require this kind of keenness, nor is it able to sustain it.

But on a razor, we do need that kind of refined keenness. While sharpening steel, at least 2 principles, both described by Prof. John D. Verhoeven of the Iowa State University in his famous study on knife sharpening, are working together to shape the edge:

1. abrasion: steel particles are knocked off the edge by microscopic protrusions and sharp particles on a whetstone, lapping film, or a surface loaded with an abrasive compound.
Abrasion not only creates debris that is washed away with the fluid on top of the whetstone, or gets stuck on the surface of the surface. Part of it is deposited on the edge as well. It's not the kind of deposit that can be rinsed away. In fact, debris deposit is one of the contributing factors to burr formation. For this reason, many sharpeners like to aim the direction of this deposits away from the edge. The way to accomplish this, is to hone with the edge leading. Edge trailing direction does promote debris deposits at the very edge. During burr-based knife sharpening, it can easily be witnessed how edge trailing direction promotes larger burrs than edge leading. On a razor we don't create a tangible bur, but deposits are there anyway, albeit much smaller. Near the end of the sharpening, when hones are used that do only very little abrasion, this becomes less important.

2. plastic flow: on a smaller scale, the edge is not only shaped by abrasive removal of steel, but also by malleability of the steel at micron level. It is the same principle that allows steel to be rolled and bend. Polishing and buffing both are surface operations that depend on various ratios of abrasion and plastic flow. The surface is shaped in a similar fashion as one can shape the surface of a block of clay by rubbing it. Also this principle is a great contributing factor to burrs folding over in knife sharpening practice. On a more speculative note, it is my personal understanding that plastic flow is 90% of the efficiency when stropping on leather. A small undefined area, existing of microscopic burr-like structures at the very edge of the razor is (re)aligned in forward direction, by a good stropping. It seems that such burr-like steel looses shape rather easily, hence the need to re-strop before every shave.

All this theory sustains the old adage that the largest portion of shaping an edge must been done in edge leading direction, this to prevent the formation of too large sections of altered steel at the very edge. During the final parts of sharpening, it becomes less important, and in some cases the more gentle action near the very edge, may speak in favor of an edge trailing approach.

I have witnessed in my own personal practice how edges that were shaped by a lot of (pasted) stropping were far less durable than those shaped by honing in edge leading direction.

Kind regards,
Bart.

 

[Fnord5]

Edge leading on hones.
Not because it's the "right" way to do it, but because it is the easiest. You need both the spine and the edge to be in contact with the hone at all times, if you lead with the spine, it is very VERY easy to let the edge lift, whereby you are only wearing down the spine.

By leading with the edge, you ensure that it is in contact with the hone, and the weight of the spine takes care of keeping it on the hone.

And if anyone is gouging a stone with a straight, you are applying WAY WAY WAY too much pressure.
You should have only the weight of the blade pressing down on the stone.

 

[Fairlight]

Edge leading on hones.
Not because it's the "right" way to do it, but because it is the easiest. You need both the spine and the edge to be in contact with the hone at all times, if you lead with the spine, it is very VERY easy to let the edge lift, whereby you are only wearing down the spine.

By leading with the edge, you ensure that it is in contact with the hone, and the weight of the spine takes care of keeping it on the hone.

And if anyone is gouging a stone with a straight, you are applying WAY WAY WAY too much pressure.
You should have only the weight of the blade pressing down on the stone.

See now, THIS I agree with.

 

[dobka]

Thank you all, gentlemen, for all this advice. I hope I am not the only one who got to understand some very important parts of razor honing.