Diamond Sharpener Medium - #400

Used the Atoma sharpener to true up my sharpening stone and it worked as expected. Had the stone perfectly flat in no time! Very high quality and a great value.

While 400 isn't quite as aggressive as the regular 320 grit you're probably used to, it's still aggressive enough to completely reprofile an edge in short order. If this isn't enough then Atoma has a 120 grit stone, which I ordered, but I'm second guessing if I'll actually use it now. The 400 takes a little more time, but you're less likely to make a mistake that damages your blade and costs you valuable edge material. Anyways, that's more about sharpening and less about the product itself. These diamond stones are the best I've used. Everything else feels like a toy, and these feel like craftsman tools. They're a little more expensive, but they're worth the cost.

Atoma diamond plates are by far the superior brand I purchased this predominantly for flattening my water stones which it does excellent at. Unlike all other diamond Stones I've purchased, it came perfectly flat! It feels very smooth and the feedback is excellent. I cannot recommend this enough if you're looking for a flattening plate or a diamond plate for sharpening Atoma should be your number one choice!

My new absolutely favorite sharpening stone brand. I will NEVER buy dmt again.I TRIED my best to stay loyal to dmt after being a loyal customer over 20 years but their quality control has gone to absolute junk, I kept getting mailed dented , chipped or completely missing coating and ruste large patches on their stones and I tried THREE other retailers not just amazon. Chinese brands have better coverage and grit uniformity than new era dmt, and these Japanese made atoma? Absolutely in a class of their own, they sharpen faster and smoother than any other syle shape or type of plate I've ever used, they have 5xmore diamonds per inch than the competition. I'm going on 40 and I have been hand sharpening since I was 9 years old , I've used wetstones,ceramics,diamond,spyderco rods etc etc etc ATOMA is my new standard, THE END.

I think these are hands down the best diamond plates on the market today. IDC what anyone says. The Japanese have practicality, time, and waste in mind when they made these. And whatever they make in general is usually done with such great detail and quality. I’ve always had respect for them when it comes to manufacturing things. 🇺🇸🤝🇯🇵I have the whole DMT set and they served me well, however the scratch patterns weren’t always the same and the diamonds weren’t nice and uniform like these are. Some of my corse DMT’s are wearing out so I looked into these. When I discovered these Atoma plates had replacement sheets available I was sold! Also the plates are made out of aluminum, which makes my toolbox a lot lighter than it was before with all of my other stones inside.This JIS 400 grit plate was able to put a bevel on my Benchmade Bugout with 20CV steel in 5 minutes. Also when you look under a microscope you can see how much better, neater and more uniform the scratch pattern is. Just remember that Japanese plates/ stones are set to ( Japanese Industrial Standard) “JIS” and American plates/Stones are set to ( American National Standards Institute) “ANSI” which if you look it up. You can see what they’re close to what you’re used to working with.All in all. Worth every damn penny!

Atoma is the only Diamond plates I will use, I use them for knives and straight razors when stone is not enough. Long lasting and dead flat.

Like competitors plates, the initial bite disappears. However, the 400 and 600 plates will last for years once initially broken in. It would be great to have the stones maintain the incredible bite they have when new!

I have the 400, 600 and 1200.The 400 is the best overall option of these 3 for initial lapping of new water stones. Lapped stones are then easily maintained with the other two. I then use the 600 for anything 5k and under. The 1200 for 8k and up.A 140 grit is available for extremely fast removal of material. But I recommend you check your stones very frequently to prevent over removal of stone. You'll also need a finer grit to remove the deep scratches from the surface of the stone.My application is for straight razor honing. A very smooth surface is more critical for such, than compared to use for other purposes.For lapping, they will perform best when fully submerged or under running water.