





💎 Sharpen smarter, not harder — the pro’s secret edge enhancer!
The DMT A4X Whetstone is a 4-inch extra-coarse (60 micron / 220 mesh) diamond sharpening stone designed for rapid edge repair on dull or damaged blades. Made in the USA with micronized monocrystalline diamonds, it offers durable, long-lasting performance without the need for oils—sharpen dry or with water. Portable and versatile, it’s ideal for professionals and enthusiasts who demand fast, efficient sharpening for knives, axes, scissors, and more.
























| ASIN | B00004WFV0 |
| Batteries Included? | No |
| Batteries Required? | No |
| Best Sellers Rank | #276,854 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #579 in Sharpening Stones |
| Brand | DMT (Diamond Machining Technology) |
| Customer Reviews | 4.6 4.6 out of 5 stars (286) |
| Date First Available | January 24, 2007 |
| Global Trade Identification Number | 00017042004439 |
| Grit Rating | 220 |
| Grit Type | Extra Coarse |
| Included Components | Diamond Whetstone |
| Is Discontinued By Manufacturer | No |
| Item Package Quantity | 1 |
| Item Weight | 0.96 ounces |
| Item model number | A4X |
| Manufacturer | DMT |
| Material | Micronized Monocrystalline Diamond |
| Measurement System | Metric |
| Number Of Pieces | 1 |
| Number of Items | 1 |
| Part Number | A4X |
| Product Dimensions | 8.75"L x 3.25"W x 2.25"H |
| Size | One Size |
| Special Features | Manual |
| Style | Extra-Coarse |
| UPC | 017042004439 |
| Warranty Description | Manufacturer Warranty |
R**O
DMT has the best diamond stones.
DMT makes the best sharpeners. Others don't use enough diamond to sharpen correctly.
W**!
Perfect for the job
These are just the right grit for putting a fine edge back on a slightly dulled knife. Don't recommend them for resharpening. You will need the blue ones for that, or even the black to start a new edge. These are fine for putting back a razor edge on a used blade that is already well sharpened.
B**O
Quality
Value
P**R
Your basic fine diamond whetstone...
This is a fine diamond whetstone used for putting the finishing touches on a sharp blade. This particular stone is for smaller blades. If you're dealing with larger tools (axes, hatchets, etc.), you'll want a larger version of this. Excellent stuff, and I'll only get these from DMT.
H**Y
Nice to have
The aligner kit that this stone works with is handy and most people should be able to put a decent edge on a knife with not much practice or know-how. This stone makes an edge good enough for average kitchen work. You do need the extra-extra fine stone to get an edge that comes close to being nicely sharp. Apparently it is expected that a diamond stone leaves a slightly rough edge. It cuts so fast and leaves tiny grooves in the beveled edge. Update 11-5-10 I may have found a significant flaw in using diamond stones to sharpen knives and tools. I am not an expert at this, and I have not seen this mentioned anywhere else, so take it with a grain of salt. The edge of the knives that I have been sharpening, while sharp, do not hold that sharp edge very long. First, no matter how well you sharpen an edge, it is not perfect. The edge has little microscopic teeth on it. Similar to a saw. These `teeth' on a knife are not uniform in size, shape, and spacing, as on a saw. Nor are they rigid as on a saw. On a knife, when you cut something, these weak little teeth bend this way or that way, and the knife begins to feel dull. My theory: Those little bits of diamond grit on a diamond stone are, as you know, very, very hard. They cut very fast. They also cut very deep. They make deeper little grooves, on the beveled edge, than any other type of sharpening stone. These deeper grooves make larger teeth on the edge of the knife. A larger tooth is inherently weaker, and will bend more easily. Also, without going into great detail, the deeper grooves cause each little tooth to have less physical support, making them weaker still. They will bend even more easily. No matter what you use to sharpen an edge, those little teeth are created. They are always present. It appears to me that a diamond grit stone causes weaker teeth that bend more easily. The result is that the edge does not stay sharp as long as when other sharpening materials are used. More comment: Because diamond stones sharpen so fast and so easily, I still like them, and will still use them. I may try to find some other sharpening stone to use as a final sharpening step, to put a more `finished' edge on a knife.
V**R
Good seller
Very good stone.
E**R
Works with Ruyxin sharpener
Works well with my Ruyxin sharpener. Note that this stones need seasoning, as is clearly stated in the packaging. That means they will end up feeling less gritty after a couple uses.
J**K
Very good - IF you need to reprofile primary bevels with your DMT Aligner
This is a pretty darn aggressive stone so ONLY buy this if you will be reprofiling your primary bevels. I do that with all my knives so this was worth it to me. I COULD have done that with just the coarse but it would have taken me much much longer without this stone. Please note: let the diamonds do the work for you - use very little or no pressure! Very gentle quick strokes are what is called for here! Note: this stone is meant to be used with the DMT Aligner. I suppose that you could use it freehand but that's not a wise thing with a smaller stone like this and setting a primary bevel ...
E**N
Me encantó afila muy bien las navajas de las fresas de router, excelente calidad muy recomendable
D**O
otimo! ja uso a mais de dez anos as pedras da DMT e vale o investimento.
M**E
I use these without the aligner sharpening jig. They help me to keep my carving tools in good condition.
J**N
Works well and fits, only use this grit to repair knife edge from heavy damage tho
A**O
Me he dado cuenta que para el 99% de los casos solo con dos hay bastante para mantener los filos, si no tiene ningún desperfecto y solo se trata de hacerle un repaso puntual, basta con usar el grano 1200 (verde), que deja un filo con un ínfimo microdentado que corta el papel de tiquet sin atascarse Si con eso no es suficiente, entonces subimos un escalón, usamos el 600 (rojo) y rematamos con el 1200 (verde) para pulir las rebabas del más grueso Con este 1200 podemos hacerle el mantenimiento preventivo a todos los filos antes de que se opaquen más y haya que tirar de granos más gruesos. Y si ya rematamos con unas pasadas en cuero podemos sacar un filo tremendo Teniendo el 600 y el 1200 ya tenemos un muy buen arsenal. Hay un grano superior (8000) pero donde esté un asentador con dos pastas creo que está un poco de más a menos que busques el pulido espejo (donde hay quien llega a grit 12000) Granos como el 325 (azul) si el filo no tiene mellas pero no corta ni un triste folio y más arriba (220) si ya hay desperfectos y rehacer el filo eliminando mucho más material Tener en cuenta que todas las placas de diamante al principio son muy rugosas y dejan el metal con más micro rayas, con el uso los puntitos abrasivos se van desgastando y el afilado queda mejor. Yo además suelo usar agua o limpiacristales, que hace que las partículas se vayan a los extremos y no se queden atascadas en el centro, y para limpiarlas uso una goma de borrar normal
Trustpilot
3 weeks ago
3 weeks ago