Diamond Pasted Balsa Polishing

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cotedupy

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These are 'diamond pasted balsa strops', and they're all the rage with some people in the straight razor community. Basically a flat piece of balsa wood with diamond paste rubbed in. It's used like a very finely abrasive pre-strop, before stropping on leather, and it makes things very sharp indeed:

IMG-5517.jpg



Diamond paste I understand is also used for mirror finishes on knives. Which I assume is done by hand - just rubbing the paste in with your finger or a bit of cloth or something? Though I think if I did that on a clad knife then it's going to start mirror-polishing the soft steel?

But on a balsa strop it doesn't seem to; I don't know if this is because of the wood, or something else, but it seemed to preserve a kasumi finish from the stone, while seriously brightening the core steel to mirror. Balsa wood also has some give to it, so it was hitting slight low spots that a stone wouldn't.

I only tried this very quickly last night using 0.1 u paste, but the results seemed quite promising I think. The scratches here are just from the previous stone, and the hard steel would have gone full mirror if I'd used a finer stone before or perhaps a progression of pastes. So I'm going to have more of a play around with it later. I've made up another piece of balsa with 0.25 u to use too.

IMG-5511.jpg


---

So... anybody else use diamond paste for polishes, with or without a balsa strop? Any tips?
 
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cotedupy

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So trying this properly, I think diamond balsa strops have some potential...

I put a finish on the blade with a Belgian Blue Whetstone (it's actually La Lorraine, but the effect is much the same):

88BBAB63-5D25-495C-B3B9-47ED2763D816.jpeg


BBW is actually a very good bevel polishing stone, and the core steel would have gone shinier if I'd worked it more, but I left it like this to see the effect of the paste after:

IMG-5520.jpg


Then used the 0.25 and then the 0.1 pasted strops above. You can only do this edge trailing btw, otherwise you'll just dig into the balsa.

I'm no polishing expert, and was only using one mid-grit stone before, so it's not completely perfect. But from start to finish, including the BBW before, this only took about 5 mins. And the effect is rather striking - the diamond balsa preserves the haze on the cladding while putting a super-bright finish on the core. I'll be doing this again I think!


IMG-5521.jpg


IMG-5525.JPG
 
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enchappo

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These results are pretty great! Is this just hardware/hobby store balsa? And if so what grade?
 

enchappo

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Balsa strops used to get talked about on here about 10 years ago, pretty sure Salty had a 4 sided block he was using when he did the OG tomato slice vids

I made a CrOx one before I realised toothy edges are better
We’re just talking about polishing here though right, not edges?
 

cotedupy

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We’re just talking about polishing here though right, not edges?

Yep I was indeed just talking about bevel polishing - I don't think the 'edges' such as they are are going to be great on kitchen knives. I'm going to sharpen a proper edge onto it with a Washita or Turkish or something now.

Re balsa - yep it's just hardware shop balsa. These pieces and the pastes were actually given to me by someone on a razor forum, so I don't know the grade. I didn't actually even know there were grades tbh, but have just searched through said forum and it seems that medium to hard balsa is preferred, so I guess it's something along those lines. While it has some give, it's certainly not the softest balsa I've ever come across.

Now that I think about it... you could probably play around with different hardness of the wood depending on how convex your main bevel is. Softer wood could be a nice solution to polishing knives with more convexed geometry. Interesting...
 

enchappo

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Yep I was indeed just talking about bevel polishing - I don't think the 'edges' such as they are are going to be great on kitchen knives. I'm going to sharpen a proper edge onto it with a Washita or Turkish or something now.

Re balsa - yep it's just hardware shop balsa. These pieces and the pastes were actually given to me by someone on a razor forum, so I don't know the grade. I didn't actually even know there were grades tbh, but have just searched through said forum and it seems that medium to hard balsa is preferred, so I guess it's something along those lines. While it has some give, it's certainly not the softest balsa I've ever come across.

Now that I think about it... you could probably play around with different hardness of the wood depending on how convex your main bevel is. Softer wood could be a nice solution to polishing knives with more convexed geometry. Interesting...
Interesting indeed. And thanks!
 
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I messed around a little with this but I much prefer edges off of stones. And I had no shortage of stones before I started with the razors so never bothered much to try and figure it out. I have waded through most of the documentation on "the method" on B&B. I think it's just a nice easy way to get people up and running to a really high level without much equipment, practice, or skill. Which, don't get me wrong, is super valuable for an insular, expensive, privately practiced, arcane grooming method to not die off. But at the same time, part of the appeal for me with all this stuff is the collecting of the historical artifacts. I like honing a 150 year old razor on a 600 million year old piece of slate that was dug out of the ground 120 years ago and then finishing it on a strop made from a horse that died 100 years ago, all produced in different countries. Something about all that is fascinating to me in a way that rubbing a Gold Dollar on a piece of wood loaded with industrial diamond jizz just can never compare to. No offense of course to anyone who is a practicing member of the method. Like I said, I respect those guys a lot and think their theory and ideas is fascinating. Just not my thing.
 

cotedupy

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I messed around a little with this but I much prefer edges off of stones. And I had no shortage of stones before I started with the razors so never bothered much to try and figure it out. I have waded through most of the documentation on "the method" on B&B. I think it's just a nice easy way to get people up and running to a really high level without much equipment, practice, or skill. Which, don't get me wrong, is super valuable for an insular, expensive, privately practiced, arcane grooming method to not die off. But at the same time, part of the appeal for me with all this stuff is the collecting of the historical artifacts. I like honing a 150 year old razor on a 600 million year old piece of slate that was dug out of the ground 120 years ago and then finishing it on a strop made from a horse that died 100 years ago, all produced in different countries. Something about all that is fascinating to me in a way that rubbing a Gold Dollar on a piece of wood loaded with industrial diamond jizz just can never compare to. No offense of course to anyone who is a practicing member of the method. Like I said, I respect those guys a lot and think their theory and ideas is fascinating. Just not my thing.

Yeah, I only tried them once properly with a razor, and I was probably predisposed not to like anyway, considering how deeply unromantic it is in comparison to all my rocks. I also didn't find the practical improvement to be all that much*. You can get excellent and smooth shaving razors with stones and a leather strop without throwing another 100 laps on something into the middle of the process for a barely perceptible gain. Though as you say - all that stuff is clever nonetheless.

This is by far my favourite use for it so far - just as a final step in a kasumi progression. It seems like it might be able to pull off that most elusive of tricks... maintaining the kasumi haze from a previous stone, while putting a full mirror on the core.

(I don't think the person who gave me these will mind me saying any of this btw. He isn't so keen on them himself, and just sent me some bits and bobs he had lying around going spare.)


---


* I was probably doing it wrong I expect. I did try to read some of the endless thread on B&B about it, but I'm not sure I took anything in.
 
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cotedupy

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Maybe it's the pre-work that made all the difference? Those super fine grits are going to be pretty sensitive to the starting surface.

The difference between the first post and the second you mean?

Probably - in the first post I'd only done a some quite quick stuff to the bevel, and then just a few strokes on 0.1 - just to see whether it was going to work. I knew that pastes were going to put a mirror on the core, but I didn't know if they were going to do something weird to the cladding.

In the second post I put a proper nice even finish on with Rouge du Salm/La Lorraine, and then spent more time on both .25 and .1. It's still not completely perfect, because of what you say - the pastes are quite unforgiving in terms of highlighting previous scratches. To do this really well and properly, I think you'd want to jump from a good fine jnat kasumi finish onto maybe 0.5 0.25 0.1 (?).

But it's interesting also because if you can't be bothered with all that faff, then it's a very easy way to get results that are pretty damn close. I quite like stone polishing because it's nice and relaxing, but I'm not particularly great at it, and sometimes I run out of patience if I'm not getting anywhere. This is quite a nice easy fix ;).
 

cotedupy

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And just to emphasize to anybody who might have one - Belgian Blue Whetstone is a really great bevel polishing stone...

Recently another member asked me about natural stone recommendations* to put a nice finish on a knife and cover up the scratch patterns after an SG500. Which isn't the easiest task in the world tbh, especially without using some mid-grit synths followed by a load of posh jnats. To be perfectly honest Japanese stones are still where it's at in terms of polishing, very few of the other things I've tried can do it nicely. BBW does though, and it's very good indeed.

SG500:

IMG-5357.jpg


Two minutes of BBW polish over the top:

IMG-5361.jpg


Firstly that probably shows you just how light and consistent the scratch pattern from the SG500 is considering its grit level, it's a remarkable stone. But also - BBW is a great polishing alternative to jnats, plus it sharpens well, and is pretty cheap. Very underrated imo.

---

* It feels somewhat weird when longstanding, very well respected guys with a ton more experience than me ask for advice / recs. But I think I managed to fulfil the brief. Was nice too because he already had a BBW, but just hadn't tried it for this.
 
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The difference between the first post and the second you mean?

Probably - in the first post I'd only done a some quite quick stuff to the bevel, and then just a few strokes on 0.1 - just to see whether it was going to work. I knew that pastes were going to put a mirror on the core, but I didn't know if they were going to do something weird to the cladding.

In the second post I put a proper nice even finish on with Rouge du Salm/La Lorraine, and then spent more time on both .25 and .1. It's still not completely perfect, because of what you say - the pastes are quite unforgiving in terms of highlighting previous scratches. To do this really well and properly, I think you'd want to jump from a good fine jnat kasumi finish onto maybe 0.5 0.25 0.1 (?).

But it's interesting also because if you can't be bothered with all that faff, then it's a very easy way to get results that are pretty damn close. I quite like stone polishing because it's nice and relaxing, but I'm not particularly great at it, and sometimes I run out of patience if I'm not getting anywhere. This is quite a nice easy fix ;).

Yes sir. I did mean between the two posts.
 

cotedupy

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Yes sir. I did mean between the two posts.

It sounds like you know more about these things than I do - I've only had these for a couple of weeks. Do you use diamond pastes either for metal polishing or razors...?

I've been struck by how fast it is for polishing - I used some to polish the main blade bit of one of my razors and it put a total mirror on in no time at all.
 
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Yeah, I only tried them once properly with a razor, and I was probably predisposed not to like anyway, in comparison to how deeply unromantic it is in comparison to all my rocks. I also didn't find the practical improvement to be all that much*. You can get excellent and smooth shaving razors with stones and a leather strop without throwing another 100 laps on something into the middle of the process for a barely perceptible gain. Though as you say - all that stuff is clever nonetheless.

This is by far my favourite use for it so far - just as a final step in a kasumi progression. It seems like it might be able to pull off that most elusive of tricks... maintaining the kasumi haze from a previous stone, while putting a full mirror on the core.

(I don't think the person who gave me these will mind me saying any of this btw. He isn't so keen on them himself, and just sent me some bits and bobs he had lying around going spare.)


---


* I was probably doing it wrong I expect. I did try to read some of the endless thread on B&B about it, but I'm not sure I took anything in.

I haven't tried it for kasumi. I think I still have mine somewhere in the basement. But I'm terrible at polishing in general so I don't know if my input will be too valuable.
 

cotedupy

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I haven't tried it for kasumi. I think I still have mine somewhere in the basement. But I'm terrible at polishing in general so I don't know if my input will be too valuable.

Haha, well I'm certainly not particularly great at it either... most of what impressed me about this was that it made me look far better than I actually am ;). So give it a go!
 
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It sounds like you know more about these things than I do - I've only had these for a couple of weeks. Do you use diamond pastes either for metal polishing or razors...?

I've been struck by how fast it is for polishing - I used some to polish the main blade bit of one of my razors and it put a total mirror on in no time at all.

My friend I assure you, you're already well beyond my experience! I was just trying to deduce what might be the variables at play. It's me dabbling vicariously in your work.

:)
 

cotedupy

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My friend I assure you, you're already well beyond my experience! I was just trying to deduce what might be the variables at play. It's me dabbling vicariously in your work.

:)

Gotcha. Though don't consider me to have any kind of polishing expertise... I'm just playing about with new toys that I thought might make me look better! ;)

But yep - I think you're spot on with what you said. Because the fine diamond paste is such a good and bright polisher it does seem to expose the previous work/scratch patterns. So either a longer diamond paste progression (which is a bit boring), or ideally - a proper kasumi progression on stones, and then just some fine diamond stropping at the end to make it really 'pop', would be good I think.
 

mrmoves92

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I tried this out, and so far it works. I tried something similar with 1 micron diamond spray on leather a while ago, and it just shined up both the core steel and the cladding for me, so I wasn’t expecting anything with this, but I was pleasantly surprised. I bought some cheap and thin balsa and I sprayed on my 1 micron diamond spray.

I had a decent polish on the left side of my knife that I finished on a Morihei 9k. The core was a decent mirror, but it was not perfect. There were some foggier sections and imperfections. I also used the knife a bit, so there was some patina built up that fogged up the mirror. I have pictures right after the Morihei 9k, with patina before the balsa/diamonds, and after the balsa/diamonds. The balsa/diamonds helped remove patina and shine up the core steel really nicely while keeping the cladding hazy. Here are the pictures of the left side (I am really sorry about the poor quality of these pictures, but hopefully they are helpful):

Right after Morihei 9k:
F3FFA165-84CB-4D35-9801-14467CE2DC69.jpeg
851FA28A-14FA-4C17-80FE-015B08863BF5.jpeg


With some patina:
F42A8F0F-1EC0-48D9-A46F-8C3B837E15F2.jpeg
EF77A0E1-51A5-4AE5-AEF3-D11F06319ADB.jpeg


After balsa/diamonds:
3BC9A12D-5E1F-4827-890E-590F613DF336.jpeg
98D1AE93-51A1-4E1E-B529-3545BD35CFAE.jpeg
E78FAE8C-AB09-4137-A32F-13CF52FA6A1F.jpeg
 

mrmoves92

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I also tried this on the right side of the knife, and it helped. The right side of the knife had a pretty bad polish from me trying out a stone powder polish. I don’t have any pictures of the polish right after the polish. There was a slight patina on the knife, the core wasn’t mirrored, and there wasn’t a lot of contrast. Using the balsa/diamonds helped create more contrast and make the core steel more reflective. Here are the pictures of the right side:

With some patina:
B1F37DE7-9DB2-467F-A0F3-70A255E6F047.jpeg


After the balsa/diamonds:
5E86DE22-7695-42C4-BD44-14D4F9B31DBF.jpeg
1863D1FB-2E9F-4C6E-BD5A-C53DD7740246.jpeg
 

Williamchan87

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I actually strop/finish with a compound brick that leaves a mirror polish. even if i only sharpen to 1k
 

kayman67

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I tried this out, and so far it works. I tried something similar with 1 micron diamond spray on leather a while ago, and it just shined up both the core steel and the cladding for me, so I wasn’t expecting anything with this, but I was pleasantly surprised. I bought some cheap and thin balsa and I sprayed on my 1 micron diamond spray.

Surface makes a great difference even with usual stropping, but it's not a popular subject.
 
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