New to straight razors - flat vs concave sharpening/honing

[Brassplyer]

Hi all - I'm brand new to straight razors - so new in fact that I haven't actually gotten a razor yet.

What's holding me up is trying to clarify issues related to honing/sharpening and how it relates to various razors.

Bear with me if this is an old news topic to you, as I say it's brand new to me.

In the first videos I watched related to honing my understanding is the vloggers were using a series of flat stones of varying grit. They emphasized the flatness issue is so important that a flattening stone is used to dress the honing stones as flat as possible. My initial impression was that's how everyone hones. I probably would have just gone online and gotten the series of stones that particular vlogger recommended except for what I describe as follows.

Then I ran across someone who indicated that certain razor makers factory hone the cutting edge of theirs with a slight concave to each side of the edge and that to maintain this concavity you have to hone it on convex stones - which require a labor-intensive process to make the stones convex. The reason being it gives a superior shave.

At the moment I'm just looking to get into straight razor use. Is it correct that many people do their entire honing process solely using a series of flat stones? Or am I misunderstanding this?

Is it possible to have a satisfactory straight razor experience without concave honing of the edge? I'm not looking to spend more and put more labor into it if it isn't necessary. I gather getting set up for concave honing is both more expensive and more labor intensive.

By all means feel free to fill in what your perceive as any misconceptions I have or gaps in my awareness - that's the whole point of this first post of mine!

Thanks!

 

[LJS]

Flat is just fine and what most folks use. No you don’t need convex hones so feel free to skip that. No you don’t want concave Good luck.

 

[Slash McCoy]

Hi all - I'm brand new to straight razors - so new in fact that I haven't actually gotten a razor yet.

What's holding me up is trying to clarify issues related to honing/sharpening and how it relates to various razors.

Bear with me if this is an old news topic to you, as I say it's brand new to me.

In the first videos I watched related to honing my understanding is the vloggers were using a series of flat stones of varying grit. They emphasized the flatness issue is so important that a flattening stone is used to dress the honing stones as flat as possible. My initial impression was that's how everyone hones. I probably would have just gone online and gotten the series of stones that particular vlogger recommended except for what I describe as follows.

Then I ran across someone who indicated that certain razor makers factory hone the cutting edge of theirs with a slight concave to each side of the edge and that to maintain this concavity you have to hone it on convex stones - which require a labor-intensive process to make the stones convex. The reason being it gives a superior shave.

At the moment I'm just looking to get into straight razor use. Is it correct that many people do their entire honing process solely using a series of flat stones? Or am I misunderstanding this?

Is it possible to have a satisfactory straight razor experience without concave honing of the edge? I'm not looking to spend more and put more labor into it if it isn't necessary. I gather getting set up for concave honing is both more expensive and more labor intensive.

By all means feel free to fill in what your perceive as any misconceptions I have or gaps in my awareness - that's the whole point of this first post of mine!

Thanks!

"Flattening stones" are an inferior method for getting your stones flat. What happens when the flattening stones aren't flat? And what effect does overrun have on the finished flatness? Best method uses a machinist's granite surface plate, with a sheet of wet/dry sandpaper stuck to it with absolutely zero wrinkles or bubbles or debris underneath. the surface plate is not necessarily expensive. Mine cost I think $45. You can do just fine with 3/4" thick (thin stuff will flex!) 12x12 acrylic. High quality plate glass at least 3/8" thick will sort of work. A polished marble floor tile MIGHT be flat enough. the sink cutiout from a polished granite countertop will usually work. Or you can just forget about lapping a bunch of rocks, by honing on lapping film, instead. At any rate, I recommend you do not use convex stones, if you use stones.

I MOST STRONGLY suggest that you will have your hands full learning to shave. Don't compound your troubles by trying to learn to shave with a razor that you are at the same time trying to learn to hone. It is frustrating and confusing. You won't even know if you have a shave-ready, shave worthy edge. (hint: you probably won't.) Learn to shave first, with a shave-ready razor made so by a bona fide known and respected member of the community, so that there is no doubt about the edge, and you can blame yourself for your bad shaves and know that you must correct your technique. Once you have a month of shaves under your belt, then try to hone your dull razor. DId I mention you should start with two razors, so one can be honed while the other is in use?

When you are ready to try honing, read the below linked thread and all threads linked within it. REad from beginning to end. THis is important because The Method was developed gradually and some things changed along the way, and other things didn't and were only mentioned early in the relevant thread. If you can't follow directions exactly and precisely, this probably won't work for you. At a minimum, you will get inferior results, and not the results that the Method honers get. At the worst, you won't even be able to shave with your edge at all, and you will be yet another tumbling tumbleweed blown across the honing landscape, rootless and directionless. Most honers require months or years, and spend many hundreds of dollars, before they consistently create decent edges, let alone better than professional edges. Do you think you got what it takes?

Newbie Honing Compendium | Badger & Blade

 

[JPO]

Hi all - I'm brand new to straight razors - so new in fact that I haven't actually gotten a razor yet.

What's holding me up is trying to clarify issues related to honing/sharpening and how it relates to various razors.

Bear with me if this is an old news topic to you, as I say it's brand new to me.

In the first videos I watched related to honing my understanding is the vloggers were using a series of flat stones of varying grit. They emphasized the flatness issue is so important that a flattening stone is used to dress the honing stones as flat as possible. My initial impression was that's how everyone hones. I probably would have just gone online and gotten the series of stones that particular vlogger recommended except for what I describe as follows.

Then I ran across someone who indicated that certain razor makers factory hone the cutting edge of theirs with a slight concave to each side of the edge and that to maintain this concavity you have to hone it on convex stones - which require a labor-intensive process to make the stones convex. The reason being it gives a superior shave.

At the moment I'm just looking to get into straight razor use. Is it correct that many people do their entire honing process solely using a series of flat stones? Or am I misunderstanding this?

Is it possible to have a satisfactory straight razor experience without concave honing of the edge? I'm not looking to spend more and put more labor into it if it isn't necessary. I gather getting set up for concave honing is both more expensive and more labor intensive.

By all means feel free to fill in what your perceive as any misconceptions I have or gaps in my awareness - that's the whole point of this first post of mine!

Thanks!

Try to get a razor or two without major geometry and grind issues. It is allot easier to hone a good blade, but a bad blade will teach you more about honing then a good one.
The convex vs flat hone seems to be a really polarizing subject. There is i thread called the convex club which covers the topic.
In my opinion a convex stone is just another tool. One of the first mistakes some people do in the beginning is to use to much pressure. When you work on a convex surface you are working on a smaller area of the bevel, this will require even more pressure control.
A really good middle ground is narrow hones, like the shapton glass stone seven.

 

[BBS Kirk]

I would suggest flat hones all the way. They are easier to maintain.

 

[Darth Scandalous]

Lots of people have been getting good edges from flat hones for a long time. And with a remarkable variety of media: natural stones from various areas, synthetics waterstones, Shapton glass, lapping films on flat plates, etc.

I have no doubt that someone can get a great edge off a convex hone, once they dial in the technique. But a better shave? I haven't tried one, but it would have to be quite good, indeed, to beat the best edges I have experienced off of flat hones.

 

[buca3152]

IMO it makes no difference whether you use a convex or a flat stone. The amount of deflection and change in the blade are so tiny and miniscule. I believe you can use a cylindrical shaped hone too. But that would be the same issue. You would gain nothing and then add another variable.

 

[Steve56]

The amount of concavity over the width of a hair is practically zero.

 

[cugel]

 

[Brassplyer]

The amount of concavity over the width of a hair is practically zero.

My understanding is that a concave hone gives the edge more flex which supposedly provides a superior shave. Not acting as an advocate or detractor - just saying what I've heard.

 

[Slash McCoy]

My understanding is that a concave hone gives the edge more flex which supposedly <emphasis added by me> provides a superior shave. Not acting as an advocate or detractor - just saying what I've heard.

Theory and reality are not necessarily the same. You know what they say about the bumblebee, right? How happy he is, in his airborne ignorance.

With convex hones you will have a problem maintaining the same amount of convexity over the length and width of the hone, as well as from one hone to another. The benefits are dubious, perhaps non existent. I think any Method honer on this forum would unhesitantly match his edges against the best edge from a progression of convex rocks. IMHO it is a gimmick and some guys love gimmicks because it helps them to feel like they are really walking the extra mile in pursuit of the ultimate edge.

The fact of the matter is the sharpest edge you will achieve is a proper Method edge, though some other methodologies can approach this level with years of diligent experience and outlay of considerable coin. For pure comfort in absence of other considerations, the very best and I mean the VERY best natural edges may exceed a maxed out Method edge, depending on the razor. I have had some pretty sweet Jnat edges, in particular.

Feel free to experiment with this, and I am sure you can make a pretty good edge that way eventually. But it won't be anything special, if my guess is right.

 

[JPO]

My understanding is that a concave hone gives the edge more flex which supposedly provides a superior shave. Not acting as an advocate or detractor - just saying what I've heard.

When you strop a full hollow ground razor razor honed on a convex hone the pitch is different. You can in theory get a keener edge, but any flat high grit hone will do the same thing.
A convex hone can be one way to hone a razor with geometry problems.
I have one Dovo razor with a bent spine. One side of the razor can be honed using a rolling x stroke. On the other side, the middle of the razor does not make contact. This side needs to be honed in sections using a combination of heel leading and toe leading strokes. Then you need to blend it all together somehow. It can be done, but i find it difficult. Using a convex hone, or even a hone that has a wheel shape on the short axis will make it much easier.
If you buy a new razor with a bent spine you should probably send it back.

I only have one razor i struggled to hone, were my solution was a convex hone. The rest of my razors hone just fine on flat hones.
Just one solution to one particular problem.
A flat hone is essentially concave after one stroke. You finished on the dished stone you need to lap before you hone

 

[JPO]

The amount of concavity over the width of a hair is practically zero.

You are correct One layer of tape changes the angle of the edge much more then even a hone with a relatively small wheel radius. I am not able to tell much of a difference.
Here is an example for anyone that is interested in this stuff
Just imagine a larger wheel radius and a 5/8 full hollow ground razor. You are then splitting atoms not hairs in difference
A human hair is on average around 70 microns. The hollow grind difference on the bevel in this example is 0.2 microns.

 

[Legion]

Stick with flat. Using convex stones adds a level of complexity and expense that it totally unnecessary when you are learning. Once you can reliably nail edges with a flat stone, if you want to experiment, go nuts.

 

[bluesman 7]

You are correct One layer of tape changes the angle of the edge much more then even a hone with a relatively small wheel radius. I am not able to tell much of a difference.
Here is an example for anyone that is interested in this stuff
Just imagine a larger wheel radius and a 5/8 full hollow ground razor. You are then splitting atoms not hairs in difference
A human hair is on average around 70 microns. The hollow grind difference on the bevel in this example is 0.2 microns.
View attachment 1319506

Nice job! The geometry is the interesting part of the discussion to me. I do all the math, but would be hard pressed to present it so well. The only thing that I would change is to use the tangent angle at the apex instead of the angle from the middle of the bevel reveal.

 

[JPO]

Nice job! The geometry is the interesting part of the discussion to me. I do all the math, but would be hard pressed to present it so well. The only thing that I would change is to use the tangent angle at the apex instead of the angle from the middle of the bevel reveal.

I agree. This is contructive feedback. Thank you. This razor was finished on a flat jnat, giving sort of a bellied hollow ground bevel. In theory at least.
You can then combine the efficiency of the convex lower grit stone with a flat finisher.

 

[Steve56]

Thank you JPO!

 

[Frank Shaves]

One step at a time. Get yourself a shave-ready straight razor and learn to shave with it. Then learn to finish/touch-up the edge of the razor using a flat surface. If you are then not happy with the results, then you might want to think about surfaces that are not flat.

 

[H Brad Boonshaft]

Flat-ish, obsessive flatness is not necessary, smooth is more important than dead flatness.

There is only one “Person” promoting convex stone and ironically, he is or was selling them and a concave plate to make convex stone…

There is always some barker hocking the next, New, new thing.

You might want to look at some of his other videos, then decide if he is someone who’s advice you want to follow.

 

[JPO]

The only way you can learn is to get your feet wet, one way or the other. There is plenty of good shoulders you can stand on to avoid most of the basic mistakes, and get a good start. I does not need to be complicated.
Getting to 95 percent edge performance can be easy. Then you can spend the next 10 years working on the last 5 percent looking for the unicorn edge for you. The same goes for shaving with a SR.
It can be a steep learning curve if you try to master everything at once.