Wrought clad polishing advice?

[KenjiF]

Any tips for wrought-clad knives on Jnats? I picked up my first 3 recently and a wrought kiri and am finding wildly different results between them on the same Jnat stones. I'm guessing 3 things are coming into play here and they are, how fine the grit is to bring out details, burnishing parts with harder stones, and also how reactive the stones are (etching parts of the cladding that are more reactive). I don't really know the composition of wrought iron but it does feel softer than other cladding I've worked on. Do you all have any tips on the type of stones and technique that generally work well for wrought to bring out the maximum details?

thanks!

 

[ethompson]

Ahh, one of the great enigmas of polishing... In general it’s about finding the right match between stone and blade for the finisher and then being patient with surface prep. The very thing that makes wrought iron beautiful can also make it tricky to polish blade to blade - it is inconsistent. Depending on the hardness of the iron, the shape of the bevel, etc. the same stone will give different results on different knives. If you don’t have a range of finishers (and I can’t blame anyone for not), at least you’ll need to modify how you use a certain stone to get the desired results - whether through surface prep, slurry management, or pressure management.

In general the finer the grit and the cleaner the surface the more clearly you will be able to see the details. Burnishing, which is strongly correlated with hardness IME, also shows details well. Something like a really hard vintage natsuya and a exceptionally fine Nakayama kiita will both show details, just in very different ways.

It takes a lot of practice to learn what types of stones and techniques yield certain finishes. After extensive reps you begin to keep a bit of a mental roster of polishes and get a better feel for what’s possible on a certain project and what it’d take to get there.

 

[KenjiF]

Yep that’s what I feared. Lucky I have more stones on the way…

 

[ReiHamono]

Akapin, shiro nagura (burnish), uchigamori

Use lots of bicarbonate in your water to prevent rusting

Super easy, I’ve never had any issue making any wrought iron do what I want with these stones and this process process

Shameless plug

https://www.kitchenknifeforums.com/threads/syoubudani-aakapin207mm×75mm×55mm2-3kg.62822/

 

[KenjiF]

Akapin, shiro nagura (burnish), uchigamori

Use lots of bicarbonate in your water to prevent rusting

Super easy, I’ve never had any issue making any wrought iron do what I want with these stones and this process process

Shameless plug

https://www.kitchenknifeforums.com/threads/syoubudani-aakapin207mm×75mm×55mm2-3kg.62822/

My uchi definitely works the most consistently. The finish from that Akapin was very surprising to me when I saw it... really nice. It's definitely tempting. I have quite a few softer stones and I'm a bit of a masochist so I've been looking for hard and fine final finishers lately.

 

[ReiHamono]

Pick up a shiro nagura and burnish with it if you want highest detail possible

This member can get you set up with an affordable bench size shiro nagura

https://instagram.com/hk.knifeworks?igshid=MzRlODBiNWFlZA==

My uchi definitely works the most consistently. The finish from that Akapin was very surprising to me when I saw it... really nice. It's definitely tempting. I have quite a few softer stones and I'm a bit of a masochist so I've been looking for hard and fine final finishers lately.

 

[nakiriknaifuwaifu]

Pick up a shiro nagura and burnish with it if you want highest detail possible

In general the finer the grit and the cleaner the surface the more clearly you will be able to see the details. Burnishing, which is strongly correlated with hardness IME, also shows details well. Something like a really hard vintage natsuya and a exceptionally fine Nakayama kiita will both show details, just in very different ways.

It takes a lot of practice to learn what types of stones and techniques yield certain finishes. After extensive reps you begin to keep a bit of a mental roster of polishes and get a better feel for what’s possible on a certain project and what it’d take to get there.

there is no "one stone best for details"

 

[ReiHamono]

Ya think?

It’s not literal, it’s a subjective matter based on each individuals experience thus my suggestion.

But thanks anyways

there is no "one stone best for details"

 

[ethompson]

IME the only absolutes in polishing are 1) geometry rules all & 2) there are no other absolutes

 

[nakiriknaifuwaifu]

Ya think?

Only sometimes
I think we're usually on the same page with regards to polishing, but just clarifying blanket/authoritative statements like that for the new polishers here trying to learn.

@KenjiF said he just picked up his first Jnats and he's getting a feel for polishing in general, I'm not sure "buy X stone that is the best for details" or "buy x progression it always works" is responsible advice (nor do I think it would magically improve his polishes).

Every stone is a compromise... Some compromises are overall better than others and some compromises suit certain tasks and materials better than others. For example you tend to lose contrast when you go up in grit (say going from aoto to uchi or nagura or suita or whatever), but how much contrast you can keep (given optimal technique) depends on the qualities of the stone. Even the type of polish that people like to see on knives are different (how much contrast, how much refinement, what kind of details, etc.)

IME the only absolutes in polishing are 1) geometry rules all & 2) there are no other absolutes

I'd add that the very low grit natural stones are IME universally garbage for material removal relative to their synthetic counterparts.

 

[ethompson]

Oh, yeah, low grit natties are just garbage in general

 

[KenjiF]

I appreciate the answers. I could have worded the question clearer. I am aware that matching the stone to the steel and iron is an art and will differ between blades. I was interested in the stones more experienced folks reach for when tackling wrought specifically and what their opinions were on why they think those stones have more success. As there are stones that will probably work well for honyaki or have a high chance of leaving scratches on soft iron clad I thought there may be some commonalities (stones and technique) that work well for wrought and may differ from other cladding I'm more experienced with.

Every stone will be a guess as to if it will work well for that particular blade but id like to be making more educated guesses and less random ones.

I'll post some tests soon.
Thanks!

 

[lesslemming]

Any tips for wrought-clad knives on Jnats? I picked up my first 3 recently and a wrought kiri and am finding wildly different results between them on the same Jnat stones. I'm guessing 3 things are coming into play here and they are, how fine the grit is to bring out details, burnishing parts with harder stones, and also how reactive the stones are (etching parts of the cladding that are more reactive). I don't really know the composition of wrought iron but it does feel softer than other cladding I've worked on. Do you all have any tips on the type of stones and technique that generally work well for wrought to bring out the maximum details?

thanks!

You should try my Maruoyama Sunashi

Honestly, it also depends on how you define details and what you expect. If what you’re looking for is a striking amount of detail visible from across the room I would go for a very reactive stone such as a Maruoyama, let the slurry do its work and then tone down the contrast to reveal more detail.

If you’re looking for subtle but fine detail on an otherwise very bright finish go for a hard stone that burnishes, like a Nagura bench stone

 

[user 16756]

I guess we all have different perspectives.

On what stones will reveal details, what stones are particularly reactive, what stones are fine enough to call finishers.

I appreciate the answers. I could have worded the question clearer. I am aware that matching the stone to the steel and iron is an art and will differ between blades. I was interested in the stones more experienced folks reach for when tackling wrought specifically and what their opinions were on why they think those stones have more success. As there are stones that will probably work well for honyaki or have a high chance of leaving scratches on soft iron clad I thought there may be some commonalities (stones and technique) that work well for wrought and may differ from other cladding I'm more experienced with.

Every stone will be a guess as to if it will work well for that particular blade but id like to be making more educated guesses and less random ones.

I'll post some tests soon.
Thanks!

one thing that makes it hard to give advice is that within hard stones there can be a fair bit of variance between how likely a stone is to pull iron, especially softer iron.

if I might give you some advice, it would be that on wrought, especially interesting wrought iron, the likelihood that a stone will pull iron goes up a lot. so the same techniques you use to manage harder/finer stones will need to be employed, but you'll have less margin for error. so water management is pretty critical, the correct amount of pressure too. this usually means err on the side of maybe slightly too much water, and too little pressure.

also, I aggressively bevel my harder stones. I will give up a bit of real estate (and it's not much), just to be sure I dont catch anything by accident.

that said, if your bevel is in good shape, you will make a lot of contact with your stones, and that helps a ton IME.

 

[KenjiF]

I guess we all have different perspectives.

On what stones will reveal details, what stones are particularly reactive, what stones are fine enough to call finishers.



one thing that makes it hard to give advice is that within hard stones there can be a fair bit of variance between how likely a stone is to pull iron, especially softer iron.

if I might give you some advice, it would be that on wrought, especially interesting wrought iron, the likelihood that a stone will pull iron goes up a lot. so the same techniques you use to manage harder/finer stones will need to be employed, but you'll have less margin for error. so water management is pretty critical, the correct amount of pressure too. this usually means err on the side of maybe slightly too much water, and too little pressure.

also, I aggressively bevel my harder stones. I will give up a bit of real estate (and it's not much), just to be sure I dont catch anything by accident.

that said, if your bevel is in good shape, you will make a lot of contact with your stones, and that helps a ton IME.

Thanks that is great advice. I have been finding stones pulling iron much easier on the wrought. Also tested a new stone last night and forgot to bevel the edges and as soon as I got close to the handle and some hit the area I was blending longitudinal convexity I hit the stone edge and left nasty (back to 1k) scratches on the bevel.

Geometry is definitely key. It's easy to pull a great finish off a Kiri or Kanna but much harder on a non-dead flat grind.

 

[KenjiF]

@lesslemming I'm definitely interested in trying both. Nagura bench stones seem like a whole new rabbit hole when I research them...

 

[Steve56]

I’ve polished a number of knives, and understand the basics of JNat polishing anyway. I’m not familiar with the term ‘pulling iron’. What does this mean, streaking soft iron? What does ‘pullling‘ look like? I’m probably familiar with it though not the word.

 

[ethompson]

Ever experienced the phenomenon of a really hard stone feeling grabby and then next think you know you feel something awful, hear a bad noise, and see a 400 grit gouge in your bevel? It’s that. Not sure what causes it but it feels like the stone tears out a chunk of iron and then like a loose diamond rubs it into the bevel. That’s the extreme version at least. Often it’s just sudden scratchiness and streaks associated with a very hard stone and terrible grabby sharpening feel

 

[KenjiF]

We need a lingo/slang glossary. hard stone, soft iron, too much pressure, and instead of the stone breaking off tiny particles it breaks off a chunk and gouges your iron is what I thought so...same as @ethompson

 

[lesslemming]

Ever experienced the phenomenon of a really hard stone feeling grabby and then next think you know you feel something awful, hear a bad noise, and see a 400 grit gouge in your bevel? It’s that. Not sure what causes it but it feels like the stone tears out a chunk of iron and then like a loose diamond rubs it into the bevel. That’s the extreme version at least. Often it’s just sudden scratchiness and streaks associated with a very hard stone and terrible grabby sharpening feel

Thanks for the explanation, I encountered that last night as well. Didn’t know there was a term for it

 

[KenjiF]

Thanks for the explanation, I encountered that last night as well. Didn’t know there was a term for it

Telling the difference between the stone ‘pulling iron’ and atoma dropping a diamond and getting lodged in stone is still a skill I’m learning…

 

[Dan-]

That’s odd…it suddenly sounds scratchy. ..keeps going…****

 

[lesslemming]

Telling the difference between the stone ‘pulling iron’ and atoma dropping a diamond and getting lodged in stone is still a skill I’m learning…

The only way to know is not using an Atoma and still having the problem

 

[mockit]

I wonder if at a certain point something like a nanohone nl8 becomes prudent for flattening these really fine stones. Do they still shed diamonds like the atoma? I know a few people on here have them. Never really considered them personally but I could see them having a place if they eliminate this problem!

 

[user 16756]

I wonder if at a certain point something like a nanohone nl8 becomes prudent for flattening these really fine stones. Do they still shed diamonds like the atoma? I know a few people on here have them. Never really considered them personally but I could see them having a place if they eliminate this problem!

the really expensive nanohone diamond plates are bonded completely different from atoma/dmt/etc plates and my understanding is they do not.

that said, I still havent pulled the trigger on one since I have several atomas, but I do plan to when I wear out the next one.

 

[ethompson]

I wonder if at a certain point something like a nanohone nl8 becomes prudent for flattening these really fine stones. Do they still shed diamonds like the atoma? I know a few people on here have them. Never really considered them personally but I could see them having a place if they eliminate this problem!

Super fine naturals rarely need a real flattening, they just don’t really wear all that much. And if they do need a surface refresh I’ve never had a problem using an atoma then scrubbing the surface of the stone with a strong sponge or stiff plastic bristled brush after. You could run a nagura over the top after atoma also if you’re still worried about loose diamonds. I’ve got no problem spending money on synths when it makes getting to the fun natural stuff easier (looking at you 9 NSK stones…), but I haven’t spoken to anyone who’s given me a really compelling case for spending many, many atomas worth of money on the nanohone plates

 

[user 16756]

there's also the grey surfacing blocks that Maxim/JNS sells. I picked one up and it's good for ensuring the surface is nice and clean.

I rarely force slurry these days so the fact you give that up to clean the surface after using a plate isn't a big deal to me.

 

[mengwong]

the really expensive nanohone diamond plates are bonded completely different from atoma/dmt/etc plates and my understanding is they do not.

I just got an NL-8 lapping plate and that one is the only diamond plate that I can use a slurry off as it doesn't drop diamonds.

 

[KenjiF]

Testing out a really hard new asagi and crackle crackle we have some pulled iron. Luckily I pulled it off quick but back to 3k for this guy.

 

[KenjiF]

I do have the nl-8 and I really like it. I wouldnt reccomend it to anyone spending under an hour or two a week polishing. I’ll wear through a 140 grit atoma in a few weeks and I don’t see myself wearing through this guy anytime soon. It doesn’t drop diamonds at all but it’s not as fast as a fresh 140 and you don’t want to be rounding over the edges of your stones with it. That said I’m sure it will pay for itself in a year with how many atoma plates I go through. It also gets finer as move up a progression if you don’t refresh it on a coarse stone so by the time I’m on Jnats it’s fine enough to dress those stones.

I haven’t used NSK but it will flatten the diamond plates I have.

I haven’t worked with the slurry from it enough. Even with my finest hardest stones I tend to just work with the swarf and tiny amount of slurry the knife will create. I’ll probably start experimenting more as I have a few hard naka tomae that I just sealed.