What's better than an Atoma 140?

[wbusby1]

Hi All,

I just bought my 14th or so Atoma 140. I use them for grinding/thinning/reshaping edges and also for stone flattening. I sharpen professionally and go through them faster than I'd like. Are there any alternatives?

I feel like Miles Aranyik once referenced a hexagonal diamond pad of some sort? The local knife shop recommends and uses a 400grit ventriculated (??) diamond stone that costs $400, I'm down to drop that much if it lasts as long as they say but my concern is that 400grit is so much finer than the 140 atoma that I can't believe it could keep up speed wise. Speed matters for me/ my business.

Thoughts/recommendations?

 

[Lars]

Belt grinder..?

 

[Barmoley]

If you bought vitrified diamond stones, you wouldn't have to flatten these that often so maybe won't need that many Atoma 140s. Quality 400 vitrified diamond stones are fast, but I wouldn't use them to flatten other stones though. Many people swear by nano-hone diamond plates for stone flattening. They are not cheap, but many are very happy with them. Maybe something like that plus 400 vitrified diamond stone exclusively for steel. Not a cheap package, but if you do this professionally, seems like it would be worth it.

 

[M1k3]

2 x Atoma 140?

 

[BillHanna]

2 x Atoma 140?

Technically correct. The best kind of correct.

 

[Heckel7302]

Maybe DMT? Never tried them.

In general, is there a reason you are using diamond plates to grinding/thinning/reshaping rather than stones? Atomas are so expensive and steel really wears them out quick. Stones would be much more economical.

 

[wbusby1]

The few coarse stones I've tried (a 140 grit and the JNS 320) dished SO FAST and wore the heck out of the atomas flattening them. Also they were thirsty as heck. Diamond plates in my experience are way faster than those stones. and the stones clog. Can say from experience DMT are way inferior to Atoma.

 

[wbusby1]

If you bought vitrified diamond stones, you wouldn't have to flatten these that often so maybe won't need that many Atoma 140s. Quality 400 vitrified diamond stones are fast, but I wouldn't use them to flatten other stones though. Many people swear by nano-hone diamond plates for stone flattening. They are not cheap, but many are very happy with them. Maybe something like that plus 400 vitrified diamond stone exclusively for steel. Not a cheap package, but if you do this professionally, seems like it would be worth it.

the 400 vitrified diamond are "fast" compared to a 400 grit stone or still comparably fast to a 140 Atoma? I use an atoma 140 because it removes steel so fast. I couldn't imagine thinning and reshaping edges with a 400 grit stone, it would take way too long.

 

[Rangen]

I thought that Mr. BBB invented his super-vitrified 400 grit diamond stones to solve almost exactly this problem. Yeah, diamond plates are great, but wear out fast if you use them for heavy metal removal.

I believe that JKI offers a 300 grit diamond stone that is very much intended for this kind of hard use, also.

Both are expensive, but maybe not more expensive in the longer term than what you are doing now.

Both are also hard to find in-stock, which might be a hint that they work well. I have both, and they are awesome, but I can't claim to have stressed them as much as you have stressed your Atomas, not nearly.

You do know you can replace just the surface part of the Atoma, right?

 

[ethompson]

I second the belt grinder notation, especially since you’re doing this as a business.

 

[Barmoley]

the 400 vitrified diamond are "fast" compared to a 400 grit stone or still comparably fast to a 140 Atoma? I use an atoma 140 because it removes steel so fast. I couldn't imagine thinning and reshaping edges with a 400 grit stone, it would take way too long.

I would talk to Jon from japaneseknifeimports.com. He is a pro and would know better what works for your type of work. In addition he might have the 300 diamond stone laying around somewhere even though it is sold out. I don't know if 400 vitrified is as fast as 140 atoma in removing metal, but it doesn't leave such deep scratches that then need to be removed I presume, so you might win there. In addition it will last much longer than an atoma so there is that too. I hate using diamond plates especially coarse diamond plates on steel, so I can't tell you how the two would compare. Atoma I would imagine works faster strictly removing metal at least when it is newish, too many variables to know what would work best for you. Most people who sharpen professionally sooner or later get some sort of a mechanized device for bulk of metal removal, as time is much more expensive than a machine in the long run.

 

[lane]

The Atoma 140 and all the other better lapping plates are now saying they are purely for 400 grit and above. My experience has been that anything synthetic 220 and under will be slow to flatten and will grind up any lapping plate quickly. A traditional sedimentary JNat in coarse grits will still flatten quickly and without damage to the lapping plate, but I'm guessing you're focused on modern ceramic or related sintered stones. I've used the Nanohone 8 and 10 (I have the 10 currently) and wouldn't think of using them on any grit under 400 or 500. The inexpensive raw carbide blocks are a better solution for the coarse stones, but they grind quickly and they leave a pretty ragged surface on the target stone. A large sheet of glass and some grit at the same coarseness as the stone will do the job effectively, and if you make a slurry of the stone or make a slurry from a slightly finer stone, it'll leave a good working surface on the target stone. However, I've simply given up on 120 and 220 ceramic stones and use micro-grade 3M sandpaper on a Kasfly sandpaper holder for those sharpening needs (reshaping, thinning, tip repair, etc.). You can use the sandpaper wet on a glass sheet as well for small amounts of lapping. I'd say that before you spend a lot of money, think about first getting rid of the stones below 320 grit or use cheap sedimentary stones, sharpen with some of the high-tech 3M sandpapers or sanding meshes, and then use the Atoma 140 or a Nanohone lapping plate to lap the higher grit stones.

If you're trying to move a good bit of metal, invest in a Burr-King. It's far from the cheapest, but it's the tool that so many great knife makers use to shape and bevel blades. You can consider something like a Tormek or a low-temp wheel on a grinding wheel, but the Burr-King is frankly better and infinitely much more flexible.

 

[Rangen]

The Atoma 140 and all the other better lapping plates are now saying they are purely for 400 grit and above.

Not the Nanohone NL-4. They are still saying 120-1500 grit.

 

[Heckel7302]

The few coarse stones I've tried (a 140 grit and the JNS 320) dished SO FAST and wore the heck out of the atomas flattening them. Also they were thirsty as heck. Diamond plates in my experience are way faster than those stones. and the stones clog. Can say from experience DMT are way inferior to Atoma.

Maybe Shapton Pro 120? It eats metal and I don’t find dishes super fast. I use a cheap 80grit diamond pad to refresh and flatten.

But if you are doing this as a business, it’s probably going to save a lot of time and expensive plates to invest in a good belt grinder.

 

[Illyria]

100% invest in a variable speed belt grinder. Also consider a kasfly sandpaper holder.

 

[lane]

True, but they also specifically say it's not for sintered ceramics and go on to say it's really made for their own soft stones. Quite a difference.

The design of the NL-4 is different -- it's not optimized for as long a life but it removes loose coarse-grit slurry from the abrasive surfaces faster by keeping the abrasive surfaces to thin strips.

 

[ReiHamono]

Gritomatic 120
Manticore 60

https://www.baryonyxknife.com/bambest.html
I would use a horizontal wheel first then refine with these

But really a super precision 3d CNC is where it’s at

 

[lane]

I've tried the SP120 a couple times. It always glazes quickly for me and takes a lot of lapping before the stone is usable the first time. I've seen that commented broadly in this forum. The SG120 does a bit better, but still needs help. Honestly, I think when you're in that grit range a solid stone is always going to have limited effectiveness. It clogs quickly and glazes, the coarse grit doesn't sinter or bond as well as finer grits and tears out faster, and it simply doesn't have an effective lifetime. A quality belt grinder is the best if you can afford it and will do it very quickly. I have the Burr-King and can attest to how well it works. If you're trying to make money at sharpening, it's the way to go. For occasional need, I have the KasFly sandpaper holder (get the big one) and if you use the technical 3M grits, it works quite well.

 

[M1k3]

Belt grinder for ultimate speed and just works.

Shapton Pro 120 is to finicky.

Coarse India or Crystolon would be a decent alternative.

 

[MowgFace]

 

[zizirex]

belt grinder.
2x48 or 2x72

 

[Benuser]

My perspective as a home user is a bit different, and I'm certainly not looking for any powered equipment. I use the Atoma 140 only for flattening stones. For fast & dirty thinning of others' stainless — think Globals, Wüsthof — I use automotive sandpaper.

 

[Leo Barr]

Hi All,

I just bought my 14th or so Atoma 140. I use them for grinding/thinning/reshaping edges and also for stone flattening. I sharpen professionally and go through them faster than I'd like. Are there any alternatives?

I feel like Miles Aranyik once referenced a hexagonal diamond pad of some sort? The local knife shop recommends and uses a 400grit ventriculated (??) diamond stone that costs $400, I'm down to drop that much if it lasts as long as they say but my concern is that 400grit is so much finer than the 140 atoma that I can't believe it could keep up speed wise. Speed matters for me/ my business.

Thoughts/recommendations?

I use the Atoma 140 for flattening stones for thinning I use a SG120 or Shapton 120 or you can use low grit sandpaper to thin I don't flatten stones under 600 with the exception of a Naniwa 400 which I use to sharpen steak knives.
I have tried repairs & thinning using Atomas but I would estimate they become pretty ineffective after around 5 knives.
You can always use the side if the stone for tip repairs.
I find since the low grits are mainly used for thinning I find they don't dish although often I find the opposite the ends of the stones wear more which is no big deal its probably because I put more pressure on the blade when it is closer to me & once I notice its got more height in the middle I will concentrate more on that area.
This way I get quite a lot of use from an Atoma I do sometimes use the Shapton dressing stone the little round one now and again on the low grits but mainly to remove swarf.
Machinery is not an option for me since I am sharpening in restaurant kitchens.
So the Atoma gets used on synthetics between 600-6K I use a Shapton glass flattening plate on naturals.

 

[MowgFace]

My perspective as a home user is a bit different, and I'm certainly not looking for any powered equipment. I use the Atoma 140 only for flattening stones. For fast & dirty thinning of others' stainless — think Globals, Wüsthof — I use automotive sandpaper.

After 14 Atomas, you’re still thinking no powered equipment?

 

[Benuser]

Any idea how much sheets of coarse sandpaper you may buy for the price of one single Atoma? Sure, the Atoma is great in removing a lot of steel, but so is sandpaper — without leaving deep grooves.

 

[cotedupy]

Cocaine, pizza, the sound of angels laughing...

That's about it.

 

[gc0220]

If you bought vitrified diamond stones, you wouldn't have to flatten these that often so maybe won't need that many Atoma 140s. Quality 400 vitrified diamond stones are fast, but I wouldn't use them to flatten other stones though. Many people swear by nano-hone diamond plates for stone flattening. They are not cheap, but many are very happy with them. Maybe something like that plus 400 vitrified diamond stone exclusively for steel. Not a cheap package, but if you do this professionally, seems like it would be worth it.

For glorified rebranded glass stones the nanohone stuff is obviously pricey but quite good. Noting special over a shapton glass, but those are probably the best performing and best overall splash and go stones on the market. Their flatting plates are just silly though. And for what, to accomplish the same thing as you could do with a sheet of glass and sandpaper or carbide powder? They're overpriced for starters but also totally unnecessary, even if you are working with single bevel knives, plane tools, straight razors. The plates which aren't even wide enough to cover the entire surface of the stone are particularly stupid. Anyhow, so you get your stones perfectly flat, then as soon you start using them they're no longer perfectly flat. What is the point in that? Paying the silly markup and presumably for such a tight tolerance on the flatness of the plate doesn't seem to make a lot sense to me. If there's anything to it, I'm all ears. For my money, I'd take a $50 atoma over any of those plates all day. It's plenty flat enough for dealing with a waterstone, and it's wide enough.

As for OP, I'm not a big fan of the DMT products, but they make some EXCELLENT lapping plates. It costs more than an "economical" atoma, but for your use case it's absolutely worth it. Most normal people could get away with just using the standard course 325 as a replacement for the atoma 400. Same sort of thing. But they have a line of products which use what they call "hardcoat" designed to put up with the rigors of abrading stuff like say ceramic. I like to use one of their little I think it's 1"x4" or so hardcoat plates as a little fixer and slurry generator too. If you only wanted the 8"x3" size, you can get into one for probably around $130. The standard ones are like 10"x4" or something like that and they generally cost $175-$200. If you have such a need though, they are well worth it. I just checked, and edited my prices, there are two grit options, 120 or 160 grit, 120 micron or 95 micron.

 

[wbusby1]

Any idea how much sheets of coarse sandpaper you may buy for the price of one single Atoma? Sure, the Atoma is great in removing a lot of steel, but so is sandpaper — without leaving deep grooves.

Seems like vitrified diamond stone might be good but I'm intrigued by the multiple responses suggesting sandpaper and a kasfly holder. This would be a more economical option to try out first. Is there a certain type/grit of sandpaper you'd recommend? automotive in like 150grit??

Also, I appreciate the intent but I'm not going to be buying a belt grinder or any other powered tools at the moment, so please rest that advice.

 

[gc0220]

Seems like vitrified diamond stone might be good but I'm intrigued by the multiple responses suggesting sandpaper and a kasfly holder. This would be a more economical option to try out first. Is there a certain type/grit of sandpaper you'd recommend? automotive in like 150grit??

Also, I appreciate the intent but I'm not going to be buying a belt grinder or any other powered tools at the moment, so please rest that advice.

DMT "DIA-Flat" plate. One of the few DMT products I recommend. Under $200 these are an excellent choice, almost no brainer.

https://www.dmtsharp.com/sharpeners/lapping.html
Here's what they claim, and I can vouch from experience it's legit:

"

• Precision ground flat to +/- 0.0005”
• Aggressive surface to facilitate quick and easy flattening of conventional and arkansas stones and waterstones
• DMT® Diamond Hardcoat Technology™ outlasts any other diamond coated lapping plate on the market
• Largest surface area of any diamond lapping plate - 40 square inches or 50% larger than other diamond lapping plates

"

 

[Benuser]

Seems like vitrified diamond stone might be good but I'm intrigued by the multiple responses suggesting sandpaper and a kasfly holder. This would be a more economical option to try out first. Is there a certain type/grit of sandpaper you'd recommend? automotive in like 150grit??

Also, I appreciate the intent but I'm not going to be buying a belt grinder or any other powered tools at the moment, so please rest that advice.

P150 is a good one to start with. No need for a holder. I use the back of an Atoma. If you aren't afraid of some convexity you may use both edge trailing and leading; otherwise trailing only. Watch the temperature once you're reaching the edge.