Spine wear
- Thread starter manly49
- Start Date
John, I think post 24 is incorrect in that it assumes than spine wear and edge wear are equivalent and that, therefore the bevel angle is maintained. This theory falls down because the spine wears faster than the edge consequently the bevel angle is always decreasing which leads to a wider bevel and continually having to play catch up when trying to make bevel edges meet.
Razors are designed with specific spine and blade widths - once they get out of kilter it's easy to end up with problems.
Jamie's first post hit the nail on the head, use tape.
Razors are designed with specific spine and blade widths - once they get out of kilter it's easy to end up with problems.
Jamie's first post hit the nail on the head, use tape.
- Joined
- Sunday October 23, 2011
- Location
- Liverpool, UK
UKRob said:
I have to say I've never seen any evidence that the spine wears faster than the edge - in fact, you're the first person I've heard on any forum making such a claim (in generalised terms anyway - I'm sure it's possible for individual people's honing styles to put more pressure on the spine or the edge and so cause uneven wear either way).
(The bevel will widen even with even wear and a constant angle, so bevel-widening per se is not evidence of different rates of wear on the spine and the edge).
Cheers,
Alan
- Joined
- Tuesday June 11, 2013
Just a thought, surely even allowing for various honing styles the spine will wear faster given that its significantly heavier than the cutting edge or bevel ?
Terry
Terry
- Joined
- Sunday October 23, 2011
- Location
- Liverpool, UK
Johnus said:
Interesting question. My first thought is that it's more likely to do that to a near-wedge - more and more honing will take it closer and closer to being a full wedge as what little hollow there is gets honed away. I've certainly seen near-wedges honed almost as far as full wedge.
With a hollow grind, the profile is designed to keep it hollow over quite a bit of blade-narrowing, and I'd expect you'd need to seriously hone away a lot of metal before it starts behaving noticeably "less hollow". As an example, I have some full hollows that have had about 50 or 60 years of use and have spine wear commensurate with their age, and they still shave, feel, and "sing" like full hollows.
But this is a bit theoretical on my part as the closest to a wedge I actually use is about 1/4 hollow, and that's still fairly hollow (and it's a new blade). I do have one near-wedge, though I haven't got round to honing it yet. But when I do, I expect I'll use tape as it's one case where I would try to avoid widening the bevel as it can get very wide very quickly. A narrower bevel does hone more quickly - you'll get no argument from me on that one.
Terrytoolpath said:
But if the spine has a greater area in contact with the stone, then it might result in more pressure or it might result in less pressure.
And then there's the question of how you apply pressure/torque when honing - and a bit of manual pressure will surely far outweigh the weight of the blade.
I think there are just too many variables to make a generalisation either way.
I was not referring to pressure - just the fact that the spine is hitting the hone at a completely different angle to the bevel. Even a minor loss of spine width due to hone wear will start to reduce bevel angle because the edge of the blade is resting on the hone at less than 20 degrees, consequently there is insignificant loss of blade width. In order to reduce blade width e.g. to remove chips, you have to bread knife at something like 45 degrees. Only then do you start to remove significant amounts of metal from the blade width.
The Coticule.be site is a good reference point for this.
By the way, there is no such thing as a true wedge - all blades have a degree of hollow grind because they are ground on wheels. It would be virtually impossible to hone a true wedge except freehand.
The Coticule.be site is a good reference point for this.
By the way, there is no such thing as a true wedge - all blades have a degree of hollow grind because they are ground on wheels. It would be virtually impossible to hone a true wedge except freehand.
Johnus said:
Interesting, didn't see it from this angle before. My rough-and-ready rule, regardless of razor age, which seems to have served me well so far:
- hollow = 1 layer Scotch 88
- half/quarter hollow = 1 or 2 layers Scotch 88
- nearly full wedges = 3 layers Scotch 88
I once had to hone a full hollow Wacker 8/8 with an extremely narrow spine in relation to blade width - and had to go up to 4 layers of 88, so there are many exceptions to the above (i.e. not all blade manufacturers use(d) the same spine thickness to blade width ratio)!
Ultimately I decide the tape layers when I have the razor in my hand....
I'm in the tape camp but I heard that Solingen manufacturers honed without tape and then polished the scratches out before putting the blades on sale.
So this discussion will be around for a while
The Coticule.be spreadsheet is fun but I'm lazy!
And thanks to all for the tips on this thread!
Cheers Michael
OP
- Joined
- Sunday January 26, 2014
- Location
- South Wales or Nottinghamshire
- Thread Starter
- #40
So how much bevel should I see once the blade is correctly honed?
- Joined
- Tuesday February 8, 2011
All depends on the age geometry and grind, most of my razors are early to mid 20 century and all barring one they are full hollows I personally wouldn't want a bevel any bigger than 1mm, on saying that I have a custom Max Sprecher 8/8 that's a quarter hollow and that as been honed with one layer of tape and as an equal bevel that's also 1mm, you can clearly see the small but equal bevel from this photo.
- Joined
- Sunday October 23, 2011
- Location
- Liverpool, UK
UKRob said:
If honing removes a greater thickness from the spine than the edge in a perpendicular direction to the honing surface, then yes you could be right - though I really can't see why it would.
Anyway, each to his own - and judging by how nice your restores look, your method clearly works well for you.
(As an aside, I came very close to buying one of yours at a time when I couldn't really afford to, but someone helped me out by beating me to it while I was struggling with my self-control - it was that Ator in the transparent blue scales)
Cheers,
Alan
- Joined
- Thursday July 7, 2011
Bevel and spine.
Just bought one of theses Chinese razors for 6$ (thinking that I could use the scales on a Gold Dollar). The blade is far below even the quality of a Gold Dollar. It looks as if it sharpened on a 2$ knife sharpener. The bevel isn't a part of the blade. While there is a raised spine, when you try it sharpen as a razor, you hit a zone above the bevel. Even with 5 layers of tape you still don't hit the existing bevel!!
Why I bring this up is that with a razor whose spine has been abused by grinding or just extreme worn, you're going to have to do something extreme to the spine to rebuild a bevel.
I'm to the point with this one where I'm going to bread knife it back to a point higher up on the blade to find an edge that I can 'hit" with a hone.[attachment=9558]
Just bought one of theses Chinese razors for 6$ (thinking that I could use the scales on a Gold Dollar). The blade is far below even the quality of a Gold Dollar. It looks as if it sharpened on a 2$ knife sharpener. The bevel isn't a part of the blade. While there is a raised spine, when you try it sharpen as a razor, you hit a zone above the bevel. Even with 5 layers of tape you still don't hit the existing bevel!!
Why I bring this up is that with a razor whose spine has been abused by grinding or just extreme worn, you're going to have to do something extreme to the spine to rebuild a bevel.
I'm to the point with this one where I'm going to bread knife it back to a point higher up on the blade to find an edge that I can 'hit" with a hone.[attachment=9558]
