Any recommendations for a REALLY coarse diamond stone?

[Jaeger]

Hello everyone. Can you recommend a really sharp/coarse diamond stone? I have the DMT extra coarse but I'm looking for something even sharper or even coarser for high-alloy steels. A real milling cutter, so to speak... the DMT is good, but I need something with more removal capacity. Are there any recommendations?

Fabian

 

[mengwong]

i think the venev is probably about as good as it can get.

Nanohone 200 micron diamond resin, BBB 400 vitrified diamond

Just ordered a Venev 100/240 Dragon. Will update when I've received it and used it a few times.

I have zero complaints with my Ultra Sharps

the Ultra Sharps are just fine

Hey, we are discussing diamond stones here : Venev Diamond Stones: what am I getting into?
I think for the coarse stones they are the best you can use right now. Mostly precision is what it gives compared to all other whetstones.
I have tried a bunch of them and even did a video on it yesterday :

 

[captaincaed]

@milangravier has been doing some experiments with coarse stones for a long time. I believe he recently found a coarse venev diamond + SiC/AlOx powder combination he likes.

To the best of my memory, the idea was that the diamonds do the cutting, and a little abrasive powder helps refresh the stone so it continues to cut at its best speed. Diamond plates will always slow down as the diamonds wear/fracture.



The Japanese Knife Imports 300 diamond is supposed to be quite good as well, but might be a little softer than the Venev, if you’re looking for absolute flatness. More expensive than Venev, but thicker, and optimized for a sharpening shop.

Good luck on your hunt.

 

[Rangen]

A recent thread included a very interesting and plausible claim: You don't need diamonds for high-alloy steels, when using low grits. I think the argument goes something like this:

Think of a high-alloy steel as a solidified steel soup containing tiny hard carbides. Silicon carbide aluminum oxide will not cut some of the carbides. Vanadium carbides are the ones most often mentioned in this regard.

If you're going to make a refined edge that will last, in the higher grits, where the tiny carbides start to play a role, you need something that can cut the carbides. That's diamond or CBN. I have run into this with things like Maxamet or S110V, finding it hard to converge on a really good edge without diamonds/CBN.

But if you're just taking off metal, you don't need to cut the carbides, you just need to remove solidified soup, and any stone will do that.

If this is true, then the discussion would revert to the usual suspects for metal removal, Debado 180 and Shapton Pro 120 and Nanohone 200 and Sigma Power Select II 240 and so on.

 

[Jaeger]

Thank you guys. I'll read through the individual threads. venev isn't really available here in Germany... maybe I can manipulate my dmt extra coarse a bit. It wears really well in itself, but once the surface is flat, it feels as if it doesn't wear anything anymore and just slides.

Fabian

 

[ReiHamono]

Here’s one for you

https://www.gritomatic.com/products/columbia-gorge-stoneworks-8-x-3-resin-bonded-diamond

 

[M1k3]

https://hapstone.pro/stones/diamond-and-cbn/venev-8-x-3-phoenix-series-dual-side-diamond

 

[milangravier]

Honestly, what you ask is difficult.
Yes there is different options for very coarse diamond or not stones. But you can't ask magic from those stones.
DMT stones are some of the coarsest stones you can find in my opinion : because the abrasive is not inside some bonding/material, but it is put upon the plate so abrasive is exterior. If you want to have even more power : it will be or a power tool or a convex stone. Convex stones are more agressive just by the fact that they make contact on a very small surface compared to a flat stone where a lot of surface is in contact, slowing down the grinding effect.

Venev exist in 80 grit. But honestly, I don't think you will prefer it. It cut for a longer time, because there is more diamond thickness, put you will need to learn how to surface it to make it cut because thoses stones are so hard that they need surface maintenance quite often to keep their abrasive performance

 

[Jaeger]

Thank you Milan
I saw your video about surface maintenance. Maybe I have wrong expectations about what I want/need. I mean, the DMT is awesome. It flattens the bevel within no time. But as i said, once it's flat it feels like nothing really happens anymore.
I have to get more experience with it I guess

 

[milangravier]

Thank you Milan
I saw your video about surface maintenance. Maybe I have wrong expectations about what I want/need. I mean, the DMT is awesome. It flattens the bevel within no time. But as i said, once it's flat it feels like nothing really happens anymore.
I have to get more experience with it I guess

What you described is typically what happen with that sort of stone/plate, like Atoma. You have one layer of diamond fixed on the exterior of a metal plate. Once you have dull that layer, well it is finished, the plate is done, you can change it. A bit like a sandbelt, it is great at the beginning, but 15 minutes later... well not that great. 30 minutes later, you can change it.
If you don't want that behavior, you will need a stone with some bonding thickness, like venev or Nsk or Naniwa diamond, so you can resurface the stone and bring out news diamond abrasive. In the end, that's a budget and maybe a good coarse stone would be better for you. Debado 180 is nice but there can be some variations from one stone and another. I like imanishi arato 220 grit too. If you want even coarser... not easy, I did not test shapton pro 120..

 

[HumbleHomeCook]

Shawn Houston aka @Deadboxhero has done a ton of research on this subject. Driven by his love of high speed steels, Shawn needed an abrasive that could keep up and ultimately developed his own (cBN) stones. They sell out instantly but he's also posted a lot of stuff on other plates.

I thought this might be of particular interest given @milangravier's post:


And some of his other videos on dimaonds:
https://www.youtube.com/@FearNoSteel/search?query=diamond plate

 

[Jaeger]

Thank you all for your tips and help. I'll see how I can cope with the dmt and how long it will last. Maybe I just need to gain a little more experience and adapt my workflow. you gave me great tips and links. I'll find out the rest over time.

Fabian

 

[Blank Blades.]

Hello everyone. Can you recommend a really sharp/coarse diamond stone? I have the DMT extra coarse but I'm looking for something even sharper or even coarser for high-alloy steels. A real milling cutter, so to speak... the DMT is good, but I need something with more removal capacity. Are there any recommendations?

Fabian

Hey. I think ive seen you before.

 

[nakiriknaifuwaifu]

kasfly + sandpaper I have found to be a good option

https://www.namikawa-ltd.com/product/42

 

[Blank Blades.]

Hello everyone. Can you recommend a really sharp/coarse diamond stone? I have the DMT extra coarse but I'm looking for something even sharper or even coarser for high-alloy steels. A real milling cutter, so to speak... the DMT is good, but I need something with more removal capacity. Are there any recommendations?

Fabian

Having tried a lot of stuff for hard to cut steels.

I say pretty much ignore suggestions for anything other than bonded diamond.

For thinning, flattening bevels, and other stuff like that using silicon carbide, or aluminum oxide stones is just not a good option.

Though they cut the steel still. They dull basically instantly and need constant resurfacing. Its a miserable process.

 

[Jaeger]

Hey. I think ive seen you before.

I'm pretty sure we've seen us on other plattforms

Having tried a lot of stuff for hard to cut steels.

I say pretty much ignore suggestions for anything other than bonded diamond.

For thinning, flattening bevels, and other stuff like that using silicon carbide, or aluminum oxide stones is just not a good option.

Though they cut the steel still. They dull basically instantly and need constant resurfacing. Its a miserable process.

Yeah, that's why I got a DMD and a DMT. I have to get more experience with them because I want to use it mainly to create the geometry.

Fabian

 

[Blank Blades.]

I'm pretty sure we've seen us on other plattforms

Yeah, that's why I got a DMD and a DMT. I have to get more experience with them because I want to use it mainly to create the geometry.

Fabian

Yeah. I found venev was what ended up working best for that.

I imagine you should be able to get them in germany through the same channels milan used for them in france.

I imagine hapstone would sell them to germany. Since they are shipping them direct from the ukraine anyway.

 

[M1k3]

Yeah. I found venev was what ended up working best for that.

I imagine you should be able to get them in germany through the same channels milan used for them in france.

I imagine hapstone would sell them to germany. Since they are shipping them direct from the ukraine anyway.

They definitely ship to France. Don't see it being an issue to ship to Germany.

 

[Jaeger]

Yeah @M1k3 shared a link to hapstone
Didn't know they ship from UA so I guess it's not a big deal to ship to Germany

Which grit sice would you recommend @Blank Blades. ? Milan didn't work with the 80Grit (as he said in his video) for several reasons.

 

[milangravier]

Yeah @M1k3 shared a link to hapstone
Didn't know they ship from UA so I guess it's not a big deal to ship to Germany

Which grit sice would you recommend @Blank Blades. ? Milan didn't work with the 80Grit (as he said in his video) for several reasons.

Sorry, I try not to say anything wrong in my videos but it's more feedback than pure solid informations that people should follow blindly.
I got 80 + 150 and 240/400. The one I use the most is 150 indeed. But I do use 80 and others. But true is that very very coarse stones that are very hard and very flat, that work on a very flat large hard surface will have difficulties to abrase. It is just a principle. So the 80 can feel less abrasive than the 150 quite often. But when it works it just works great !
80 is a true a 150 grit I would say so if you look for something like this you should like it.

But again, Venev they are not the easiest to use and you need to give the surface some care if not it will stop cutting after a while : you can use a very coarse stone to surface it, or sic powder like 60 grit at least. Don't do it for too long, just to wake up the surface.
And I had the experience lately, if the surface start to be very wide and flat, they just won't cut if you don't put loose abrasive on the surface, because they are not soft and they don't wear much releasing abrasive they can stop cutting in some situation. I am talking about thinning here. If you use them for edge work it won't happen.

 

[Jaeger]

Thank you again Milan for all the tips
I wanna use them only for thinning and creating the geometry.
So doing the flattening with the 80 and the deeper work with the 150 should work well as I assume (with a maintained surface of course).

 

[milangravier]

Thank you again Milan for all the tips
I wanna use them only for thinning and creating the geometry.
So doing the flattening with the 80 and the deeper work with the 150 should work well as I assume (with a maintained surface of course).

I did not see you're a maker ! If the plan is to work your knives on stones and want solid stones to do that job effiently. My advise would be... buy Venev, but not only them. They are great, but again in some situations they wont be the right stones for the blade and having different stones and possibilities is a must as a maker if you want to deal with different geometry, steel, etc..

 

[Jaeger]

Exactly. I have a bunch of shaptons in different grits (coarse to fine) and they're great but not on high alloy steels. For the high carbons they're fine.
I think I got it
Thank you Milan

Fabian

 

[Blank Blades.]

Thank you again Milan for all the tips
I wanna use them only for thinning and creating the geometry.
So doing the flattening with the 80 and the deeper work with the 150 should work well as I assume (with a maintained surface of course).

I've had a similar experience to milan with the 80. The diamond can dull, or the surface loads. Cant tell which exactly but my guess is the former, and it can stop cutting after a while. The 150 does this less.

But overall i recommend the 80/150 stone for geometry setting. Cuts even the hardest to work steels I use no problem. Just needs some refreshing every once in a while. It even works well for k390 at 67 hrc, and 10v at 66.5. So i doubt there is much of anything they wont cut well.

 

[Jaeger]

Thank you guys, it helps a lot

Fabian

 

[Veitchii]

A DMT Extra-Extra coarse (120 grit) might be what you're looking for. I have one, and it's super quick and aggressive. I was flattening a hollow ground bevel 2 days ago, and it was making visible progress every minute I used it.

Heres a pic of the scratches it leaves. Ignore the scratches along and above the shinogi; those were from my very first time doing this type of work.

 

[Jaeger]

I have the DMT extra coarse already it's of course very quick but the problem is, once the surface is flat, it seems like the diamonds won't touch the steel anymore...
You can't go deeper on a flattened surface

 

[Veitchii]

They are two separate plates: the extra coarse is 220 grit while the extra-extra coarse is 120, but I apologize if you already have the latter. With my diamond plate, I havent run into the issue you're describing though. Part of it might be the increased surface area in contact with the stone slowing down the cutting after flattening a surface. Maybe crosshatching the scratch pattern on the same stone could help too; the diamonds wont run through the scratches you've already made, speeding up progress from what I've seen/heard.

Hope I was able to help a little

 

[Jaeger]

Thank you. Didn't know there is a extra extra coarse I'll try what you said
Thank you

 

[Blank Blades.]

To try to avoid making a new thread i'll ask here. But if no one see's it i might do a new one. But i think its relivant to this.

I think i'm to the point where im willing to pay that extra $$$ for some speed. Is there a consensus on what the fasted diamond stone is? I've seen the nsk one mentioned as being pretty fast.

Some say the triple b, and japanese knife imports are fast also.

I just want something fast. It wearing down quicker isn't a huge deal as long as its not like cerax 320 fast and gone in only a few knives. Since theyre like $300+