Dieter Schmid's Fine Tools
Flattening stones (truing stones), silicon carbide powder for flattening water stones

Flattening stones (truing stones), silicon carbide powder for flattening water stones

A flattening block is used to dress stones that are no longer flat enough to sharpen properly. A flat stone is indispensable for effective sharpening, especially of flat chisels and plane blades. To quickly flatten a stone, you simply move it across the surface of the flattening block with circular or back and forth movements. A steel flattening block should be used only with silicon carbide powder. A silicon carbide flattening block can be used without powder but you can speed up the process if you spread a little silicon carbide powder on the block. The latter method is strongly recommended for hard stones like those available from Shapton. But remember, if you use an abrasive powder you must afterwards rinse the sharpening stone thoroughly with water.

Naniwa 220 flattening stone (small)

220 grit grade flattening stone

  • made of silicon carbide
  • suitable for all water stones
Size 170 mm x 55 mm x 30 mm
Weight 0.5 kg

This flattening stone with its smaller surface is harder to handle than the larger version and it takes more experience and effort to achieve a good result.

Code 313207CartPrice € 17.90
Naniwa 220 flattening stone (large)

220 grit grade flattening stone

  • made of silicon carbide
  • suitable for all water stones
Size 300 mm x 150 mm x 20 mm (12 x 6 x 3/4 inch)
Weight 2.4 kg (5 lbs)

This large flattening (truing) stone is ideal for flattening the surface of sharpening stones that have become dished or have developed grooves. More ...

Code 313202CartPrice € 49.90
Juuma 220 flattening stone

220 grit grade flattening stone

  • made of aluminum oxide
  • recommended for 120 to 6000 grit water stones
Size 240 mm x 100 mm x 32 mm
Weight 1.7 to 1.8 kg

With these comfortably sized flattening stones, you can very quickly resurface hollowed sharpening stones so that they are flat and true again. In contrast to the other flattening stones listed above, which are made of silicon carbide, these stones are made of aluminum oxide, which is a sharper, more abrasive material and cuts faster than the silicon carbide. Manganese is added to increase the dimensional stability of these stones, which is why they are pink. To keep these blocks flat, you can rub two of them together, even if they have different grit grades.

Juuma 120 grit grade flattening stone
recommended for stones with grain size 120 to 6000
Code 330514CartPrice € 85.00

Juuma 220 grit grade flattening stone
recommended for all waterstones
Code 330517CartPrice € 86.00
Shapton Naoru lapping plate

Water stone correction plate for

  • dressing all water stones
  • made of steel
Size 247 x 99 x 25 mm (9-3/4 x 4 x 1 inch)
Weight 2.7 kg (6 lbs)

The flattening plate comes with two bottles of silicon carbide powder (coarse and medium). The plate has grooves to collect the slurry. This is the Japanese market version. More ...

Code 310996CartPrice € 159.00
Shapton correction powder for lapping plate

Use these abrasives on lapping plates or truing stones for fast results when flattening water stones.

Note: Not for use on diamond flattening plates!

Which powder for my stones?

Grit grade 120 correction powder
(coarse, silicon carbide)
Content 190 g
Code 310990CartPrice € 21.70
Base price € 114.21 per kg

Grit grade 180 correction powder
(medium, silicon carbide)
Content 190 g
Code 310991CartPrice € 21.70
Base price € 114.21 per kg

Grit grade 4000 correction powder
(superfine, aluminum oxide)
Content 100 g
Code 310992CartPrice € 36.50
Base price € 365.00 per kg
Silicon carbide powder (correction powder)

The additive of choice for flattening whetstones. You can really speed up the popular method – waterproof sandpaper on a glass plate – by adding just a teaspoonful of this powder. You will also increase the effectiveness of the Naniwa flattening stone with this powder. Also suitable for honing the backs of Japanese chisels blades on a steel flattening plate! Content 150 g.

Note: Not for use on diamond flattening plates!

Grit grade 60 (coarse) correction powder
Code 109025CartPrice € 4.50

Base price € 30.00 per kg


Grit grade 120 (medium coarse) correction powder
Code 109026CartPrice € 4.50

Base price € 30.00 per kg


Grit grade 180 (medium fine) correction powder
Code 109027CartPrice € 4.50

Base price € 30.00 per kg


Grit grade 400 (fine) correction powder
Code 109028CartPrice € 6.50

Base price € 43.34 per kg



Shapton Kubo K0799 diamond flattening plate

Unique two-sided flattening plate for

  • both whetstones and plane or chisel blades
  • also suitable for smaller and delicate tools
Grinding area 242 x 70 mm
Size including gum box 266 x 93 x 37 mm
Weight 3 kg

Code 310997CartPrice € 539.00

This is the most versatile and useful flattening and sharpening block available on the market today. The side with the deep grooves (top photo) is for flattening sharpening stones, the side with small perforations is for flattening the backs of plane irons, chisels and similar tools. A 70 x 48 mm area on this side is free of perforations to prevent smaller tools from catching in the surface.

Enlarged photo of side for flattening water stones
Enlarged photo of side for flattening plane blades, chisels
Flattening plate stored in rubber box

The two-part heavy rubber box serves as a slip-proof base when using the plate or as a holder for any other water stone. Use only water as a lubricant with this plate!

Note: If necessary, the diamond abrasive coating can be renewed at the factory for a charge of 250 euros (includes shipping to Japan and back to Germany).

Detailed instructions

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