Bevel polishing, stropping and bevel angle

[TheBeast]

Dear straight razor honers. I have three questions for you today.

- to what point do you chase a scratch free finish at 8k? can you still see some scratches after using just water, very light X strokes until the razor sticks to the stone? because I can see them, I just don't know how I should interpret them. with the rigth angle of light hitting the bevel it seems like a super smooth finnish, but with different angles I can make out clear glints of scratching

- does stropping usually produce more scratching? after giving my razor good stropping after getting a near mirror finnish off of 8k, there was lots of new scratches. not deep, but clearly more noticable then off the stone.

- if you want to change the bevel angle from say, from 18° to 16°, how do you do it?

I have spent my evening by training my honing skills. I noticed my experimental Gold Monkey had noticable scratches on the bevel face. So I went to my 8k and tried to get rid of them, tried different strokes, slurry and water, more and less pressure/torque etc, often inspected the bevel face during the process. I got to a point where I was quite happy, jointed the edge, brought it back just for good measure. Now there still are feint scratches that I am able to make out in certain angles of light hitting the steel.

After stropping, there are tons of little scratches all along the bevel face. Now, after stropping, the HHT result improves drastically, from only sometimes cutting the hair (fresh off the stone, no stropping), to not giving it a single chance and always confidently poping it (after stropping).

I know, the shave is what matters. I will test that later on when it's time to shave and see for myself.

I also measured bevel angles of my razors. The Gold Monkey is at around 16.5 to 17.5 along the length of the blade. It shaves better than my other razors, which I measured to be around 19°. With the Gold Monkey, I taped the edge and wore the spine down drastically. The reason was to make the razor sit flat on the hone. I knew this would bring the angle down, and it did, and I actually really like it. But I am hesitant to do that to my other razors, which are French vintage ones for about 20 dollars. I learned to hone on them after a Gold Dollar. I did lose quite a bit of blade's width in the process,I was trying to straighten the edge and remove a frown from one. I probably increased the angle after what I did to them, compared to how they came to me. Say I bought a brand new Ralph Aust for 200, would I also have to grind down the spine like that? To add angle, simple, put a layer of tape on the spine and boom, I just gained roughly 1° of angle. But to reduce the angle by 1°, I would have to reduce the spine's thickness by 2x the thickness of the tape.

 

[JPO]

- if you want to change the bevel angle from say, from 18° to 16°, how do you do it?

Tape the edge and hone the spine without changing the bevel plane geometry too much.

Say I bought a brand new Ralph Aust for 200, would I also have to grind down the spine like that?

Have you measured the bevel angle on this razor? It should already be around 16 to 17 deg.

There are also ways to improve the bevel angle without thinning the spine too much. Some new TI and Dovo razor actually come with a taller and more acute bevel from the factory. As you hone them on flat stones you reverse this, and create a more obtuse bevel.
Every attempt at discussions these topics are always shot down by Internet experts.

 

[TheBeast]

Have you measured the bevel angle on this razor? It should already be around 16 to 17 deg.

I do not have a new Rauplh Aust. The plan is to get one, once I am effecient in honing enough to reliably produce a comfortable edge suited to my needs. And use said edge well.

Every attempt at discussions these topics are always shot down by Internet experts.

I've gotten quite effecient in filtering. There is no way for me to know what an angle on a Ralph Aust is, without having one and measuring it by myself. I have no idea of konwing how to change said angle, until I do it. Thus I won't even believe what you just said until I can prove it myself (just kidding). I'm just fueling my never stopping mind. I will eventually learn everything by myself, by doing it. But a lot of pointers acquired here are very useful.



"I've seen hundreds and hundreds of vintage straight razors and if they don't get taped they get worn out on the spine and you actually have to stack tape up to get a good angle on it."

"Putting tape on the spine protects it so that it doesn't get too thin and change the angle of your edge."

-internet expert,

who probably likes the angle to be above 19° and doesn't realize the spine should wear together with the edge, because otherwise only the blade's width gets reduced, which increases the angle.

 

[Kyle89]

Can't really comment a crazy amount other than if you're chasing that hard on 8k, it may be wise to go back in the progression.

I know what my bevel looks like off of my Shapton 5k, and I know where it should be off of my Shapton 8k (which doesn't take much). It will all come with time.

When it all comes together you'll be wondering what the fuss was all about lol. Don't over think it. Hone, shave, repeat.

 

[TheBeast]

Shaving update

Good shave, very sharp edge. My sharpest yet. No tugging or pulling, no hesitation in denser growth. It just went off smoothly and fairly close. Any discomfort was user introduced. I never wielded such a sharp blade. Still less irritation than with a duller edge.

Off of 8k this razor is sharper than it was off of 0.1um diamond pasted balsa. If I had to guess, I messed up on the balsa big time. And tonight while working and working the 8k I refined the bevel and got a cleaner apex. Possibly even reduced the width on the apex by quite a bit. Because it feels miles better.

I'll repeat this a few times, work the 8k, strop and shave. See where it gets me.

 

[TheBeast]

Don't over think it. Hone, shave, repeat.

I can only shave once a day, but I can overthink the remaining 23 hours and 30 minutes...

I agree with you fully. Once it has to click, but only after trying stuff.

 

[ZeelandsRoem]

If I had to guess, I messed up on the balsa big time

Or maybe the work on the stones was not completed and tried to compensate for it on the balsa, that’s also possible.

 

[Gamma]

Honing is scratching steel.
No matter how fine the abrasive is, there will always be striations.

To alter bevel angle you have to either thin the spine or shorten the width.
the latter increases the angle, the former reduces it.
I usually narrow the spine on a DMT plate. Have to be careful and methodical so the centerline stays in the center.

Stropping on clean leather will not usually introduce scratches. Normally, plastic deformation smooths things out.
You may have dirt embedded in the strop.
You may have been fooled by what you think you saw before you got to the strop.
I can light a bevel so it looks like the honing equivalent of an immaculate conception.
I can then move the light or the blade and it can look like a crackhead's roadmap.

Mirror polish doesn't mean spit. What matters is apex condition.
Some mirror bevels shave terribly, some ugly Betty bevels rock the house.

When honing razors, I find using slurry on synthetics above the lower grits to be counterproductive.
Synth slurry does not break down, it does not make things finer. it just slams into the apex wreaking havoc, or clump and drag across the bevel, and sometimes it exacerbates an unskilled honing technique's tendency to create a burr or wire.

Feedback.
Learn to understand that the steel and stone are telling you.
Honing takes time to learn.
Overthinking things slows the learning process down.

If your edge is duller after diamond paste than it was on the 8k, it could be that you formed a wire edge or a burr on the stones and the diamond took it off.

 

[TheBeast]

Honing is scratching steel.
No matter how fine the abrasive is, there will always be striations.

To alter bevel angle you have to either thin the spine or shorten the width.
the latter increases the angle, the former reduces it.
I usually narrow the spine on a DMT plate. Have to be careful and methodical so the centerline stays in the center.

Stropping on clean leather will not usually introduce scratches. Normally, plastic deformation smooths things out.
You may have dirt embedded in the strop.
You may have been fooled by what you think you saw before you got to the strop.
I can light a bevel so it looks like the honing equivalent of an immaculate conception.
I can then move the light or the blade and it can look like a crackhead's roadmap.

Mirror polish doesn't mean spit. What matters is apex condition.
Some mirror bevels shave terribly, some ugly Betty bevels rock the house.

When honing razors, I find using slurry on synthetics above the lower grits to be counterproductive.
Synth slurry does not break down, it does not make things finer. it just slams into the apex wreaking havoc, or clump and drag across the bevel, and sometimes it exacerbates an unskilled honing technique's tendency to create a burr or wire.

Feedback.
Learn to understand that the steel and stone are telling you.
Honing takes time to learn.
Overthinking things slows the learning process down.

If your edge is duller after diamond paste than it was on the 8k, it could be that you formed a wire edge or a burr on the stones and the diamond took it off.

So the angle is now clear to me. Two dimensions that control it, gotta move them accordingly.

I have two strops. One I scratched up, got dirty, washed with a brush and a drop of leather cleaner, kept clean since. The other one is fairly new and looked after. Both produce similar results. So I'll kep honing and stroping and maybe find out one day what is going on. But stropping is not hurting my shave so all is reasonably well.

I'll put my focus on feeling rather than seeing. I got too hung up in conversations about "mirror finnish = good edge" and tried to believe it.

Until now slurry on 8k or 12k helped me get rid of scratches. Then I switched to water only and kept going until the feeling stopped changing. Smooth at first, sticky at the end - is my best attempt at describing it. Will give it a go without slurry next time.


I have no idea how to check for a wire or a burr without a big scope. When I run my finger from spine to edge and off the edge, it's not like I can feel any burr, like I would when knife sharpening on a 400 grit.
If it feels on the stone like it did last night I'm usually happy with the shave, I can joint the edge and bring it back as often as I want, it catches and moves very smootly on my thumbnail, grabs my thumpad, has a confident HHT result...

The only thing that comes to mind with my balsa strops is that the 0.5 and 0.25 feel similar, and the 0.1 feels odd. I wonder if I messed up with flattening or the paste is whack, I got that one from a guy on ebay from Ukraine. So I'll shave after each one to catch where it falls off, see what I find.

 

[JPO]

Until now slurry on 8k or 12k helped me get rid of scratches. Then I switched to water only and kept going until the feeling stopped changing. Smooth at first, sticky at the end - is my best attempt at describing it. Will give it a go without slurry next time.

When you have seen what synthetic slurry does to an edge under magnification, you will most likely newer do it again. It might help speed things up during bevel setting. After that it is counterproductive most of the time.
If you want to speed up the stone just refresh the surface, and maybe reduce the amount of water on the stone.
8k and 12k stones should not need more then some light work if the previous stones was used right.

This is a hollow grinded bevel. I am not able to do photo stacking to give the required depth of field to show this. The lower part of this bevel has a more acute bevel angle then then the edge width to spine width can give you.
Intentionally flexing the bevel over different curved stones can give you this effect.
You can even do it on flat hard stones. Shoulderless blades are good candidates for this.

You don't need to, but that is a different matter.
A bevel at e.g 18 deg might actually benefit from it, without the need to thin the spine.

 

[TheBeast]

When you have seen what synthetic slurry does to an edge under magnification, you will most likely newer do it again. It might help speed things up during bevel setting. After that it is counterproductive most of the time.
If you want to speed up the stone just refresh the surface, and maybe reduce the amount of water on the stone.
8k and 12k stones should not need more then some light work if the previous stones was used right.

This is a hollow grinded bevel. I am not able to do photo stacking to give the required depth of field to show this. The lower part of this bevel has a more acute bevel angle then then the edge width to spine width can give you.
Intentionally flexing the bevel over different curved stones can give you this effect.
You can even do it on flat hard stones. Shoulderless blades are good candidates for this.

You don't need to, but that is a different matter.
A bevel at e.g 18 deg might actually benefit from it, without the need to thin the spine.

View attachment 1730610

Well, I'll hone my next razor without slurry and see how it goes for me. I got the idea of using slurry on 8k from DrMatt's videos and his edges looked fine under magnification and reportedly shaved nice. But given the fact both you and Gamma dont like this, there will be something to it.

I should mention I need to work on 8k a lot, never just some light work

Yeah I was contemplating about similar things while giving my razor a heavier handed stropping than usual. I might have created a convex bevel while doing so. That might have been the reason why I felt the bump in sharpness. Because I noticed some scratches further away from the edge under one angle of light and finer scratches near the edge. As I tilted the razor in the light, one set of scratches dissapeared while to other showed up. It may be a result of me not being consistent in my stroke while on the 8k, so I might have cut a double bevel there with the strokes where I used more torque - probably more likely.

Interesting. I'll keep trying to improve my work in lower grits. And see if I can get to a level where only a little bit after 5k is needed, and keep the bevel flat, with only one face from edge to spine. My favourite scratches should guide me.

 

[JPO]

I should mention I need to work on 8k a lot, never just some light work

Then I would say you need to work allot on your previous stones to reduce the time needed on the stones.
If you are jumping from something like 3k you probably need to put in some work on the 8k. Having a 5-6k makes the 8k work allot easier.
Some synthetic stones actually work OK with slurry, like the 8k Naniwa Fuji.

Unless you have the same stones as Dr. Matt, I would not generalise too much.
Brute force honing might be OK with a gold Dallllla, but I would not recommend this treatment with a more expensive razor.

 

[H Brad Boonshaft]

The 8k and 12k should leave a near mirror finish. If you are scratching the bevel after stropping the strop is dirty or contaminated. Airborne dust lands on your strop daily and is larger than 8 or12k.

Wipe your strop before use with a damp microfiber or paper towel to remove the dust. Using your hand will only drive the grit into the strop.

Also, if you are not stropping on linen after shaving all that schmutz, soap, skin, blood and oxidation, (rust) is getting on your leather strop and is abrasive.

A near mirror bevel is not the goal, it is the byproduct of a 12k stone. What you do not want to see is single deep stria running to the edge, ending in a chip.

The 12k is an aggressive stone, slurry on synthetic stones it will impact the edge. Not really a big deal, nothing that 10-15 laps on a clean stone will not repair.

Also watch your pressure on the strops especially linen, flax linen can also be aggressive. A convex bevel is not a bad thing, more pressure is put on the edge than the back of the bevel when stropping.

Below is an 8k edge and a 12k edge.

8K



12k

 

[TheBeast]

The 8k and 12k should leave a near mirror finish. If you are scratching the bevel after stropping the strop is dirty or contaminated. Airborne dust lands on your strop daily and is larger than 8 or12k.

Wipe your strop before use with a damp microfiber or paper towel to remove the dust. Using your hand will only drive the grit into the strop.

Also, if you are not stropping on linen after shaving all that schmutz, soap, skin, blood and oxidation, (rust) is getting on your leather strop and is abrasive.

A near mirror bevel is not the goal, it is the byproduct of a 12k stone. What you do not want to see is single deep stria running to the edge, ending in a chip.

The 12k is an aggressive stone, slurry on synthetic stones it will impact the edge. Not really a big deal, nothing that 10-15 laps on a clean stone will not repair.

Also watch your pressure on the strops especially linen, flax linen can also be aggressive. A convex bevel is not a bad thing, more pressure is put on the edge than the back of the bevel when stropping.

Below is an 8k edge and a 12k edge.

View attachment 1730744

8K



12kView attachment 1730747

I noticed that the way those scratches look heavily depends on light. Today I was staring at my bevel with various light sources and All the angles I could think of. USB camera sees something different and is even more dependent on the way the steel is lit. If I tried, I could replicate these pictures in one shot and make it smooth as a Mirror in the other. Under sunlight the bevel is as smooth as Can be, under halogen I Can see subtle marks in direction I finnished in and under LED there Bright glints. So for now I think I am in the ballpark of where I should be in terms of removing striations from previous grits.

For stropping I always wash the razor with a wet paper towel and a microfiber. Then I lightly lap on canvas for a few laps, then clean leather. I don't want my pastes to get on the strop. I will give it a wipe and try to see a difference.

So I decided to switch my focus to feeling what is going on with the edge. And I ended up going through my balsa progression off the 8k. With a consistent stroke the razor felt subtly different on each paste, making a ring specific for Every micron stage. I kept making sure the edge Has the ability to cut hair by stropping after Every balsa step and doing HHT. The feel and sound was different after Every step. Now I Can grip the hair in one hand and bring the edge Down on the hair and cut it. Previously I could only have the edge facing Up and bring the hair down.

As always a shave will tell the whole story. I just can't keep shaving after Every stroke so I'm trying to tie the result of HHT to the result of the shave. So far it's Been really helpful and I would like to tune it in for myself.

After each day of messing around I learn more I ever could by reading and contemplating. I am starting to get a feel for it and I'm having loads of fun.

I will soon have a certified straightedge (funnily enough Made in Slovakia where I'm from), certified to the highest "category" of allowed deviation, only 0.007mm on 500mm of length. Fresh stones that won't warp and a Diamond plate that was made to be flat, not convex. So that should make my honing more straightforward. I Also picked up a Sheffield 6/8, possibly Near wedge. She will be pampered.

So thanks everyone again, progress Has Been established.

 

[Herrenberg]

I noticed that the way those scratches look heavily depends on light.

You are 100% right about that. I had to get a tilting table for my microscope, to avoid self-deception. A perfectly black uniform surface, tilted right, can yield a silvery forest of pits and low-grit scratches.

 

[Gamma]

I'll put my focus on feeling rather than seeing. I got too hung up in conversations about "mirror finnish = good edge" and tried to believe it.

You can have a mirrored bevel and a truncated apex that won't cut.

Until now slurry on 8k or 12k helped me get rid of scratches. Then I switched to water only and kept going until the feeling stopped changing. Smooth at first, sticky at the end - is my best attempt at describing it. Will give it a go without slurry next time.

If you thought you needed slurry on an 8k to remove 5k scratches, then your ground work wasn't done to completion. 8k should remove 5k work easily.

I have no idea how to check for a wire or a burr without a big scope.

You can see a burr with your eye or a 4x loupe. It catches the light on a different angle. You will see sparkles where there shouldn't be any. Burrs and foils can be caused by improper use of pressure, honing too long on one stage - doing 800 laps on an 8k for example, using slurry on synths, 1/2 strokes, too much work on pastes, etc. Using x strokes minimizes the possibility, but the rest of the process needs to be on-point. I don't know that you had a burr but it sure as heck read like that was the deal. It's nearly impossible to make an edge duller with diamond paste following an 8k. Truncating a burr with an abrasive compound is one way to do it though. A typical razor's edge might be .4 µm, a foil or burr will be exponentially thinner; so you're not going to feel it like you feel a knife burr. You learn to feel it on the stone.

I can joint the edge and bring it back as often as I want, it catches and moves very smootly on my thumbnail, grabs my thumpad, has a confident HHT result...

Nail tests are really for bevel set work. Doing that can also tear a burr off a finished edge too.

The only thing that comes to mind with my balsa strops is that the 0.5 and 0.25 feel similar, and the 0.1 feels odd. I wonder if I messed up with flattening or the paste is whack, I got that one from a guy on ebay from Ukraine. So I'll shave after each one to catch where it falls off, see what I find.

Diamond paste, any paste really, can clump and cause uneven sharpening. Cheap diamond powder can have really large particles in it. On a knife you won't notice but a razor on the face is another thing. A clunky substrate can cause issues too. But there are always going to be striations on the bevel. The mirrored surfaced is created by striations. What you can actually see depends on the light's angle of incidence, and magnification.