Diamond Blades

Diamond blade construction — and are there really diamonds in it?

A diamond blade is a cutting disc whose working part is a metal-bonded diamond sinter — synthetic diamond crystals held in a metal matrix (the bond) around the rim of the blade. To answer a common question: yes, there really are diamonds in a diamond blade, only they are produced industrially rather than being gem-grade stones. Diamond is the hardest known material (10 on the Mohs scale), which is why the blade does not cut with teeth but grinds the material away; as the exposed diamonds wear down, the bond releases the next sharp grains. The core is a steel body with a 22.2 mm or 25.4 mm bore, matched to the spindle of an angle grinder, cut-off saw or concrete saw.

How well a blade performs comes down to the hardness of the bond: a soft bond exposes fresh diamond faster in hard, reinforced concrete, while a harder bond lasts longer in abrasive asphalt and sandstone. At NORWIT.PL you will find blades primarily by Tyrolit, as well as Cedima and Nozar — from 125 mm for angle grinders to professional 350–400 mm blades for petrol machines. For the full range of cutting tools see the parent category cutting, drilling and grinding.

Types of diamond blade — segmented, continuous rim, turbo and cup wheel

Cutting speed and edge quality are decided by the rim design. A segmented blade has a rim split by gullets that cool it and clear the slurry — it cuts fastest and dry, but leaves a rough edge. A continuous-rim blade has an unbroken rim, cuts more slowly and usually wet, without chipping — the choice for porcelain, glazed tiles and clinker. A turbo blade with a wavy rim combines pace with a smooth finish and is the most versatile.

A cup wheel (diamond grinding cup) does not cut but grinds with its face — it is used to level concrete and to grind porcelain and terrazzo.

Diamond blade by material — from concrete to clinker

The single most important selection criterion is the material being cut — it determines the rim type and the bond hardness. We split the range strictly by material so the choice is unambiguous.

Cutting fresh concrete is a separate technique — cutting control joints by the Soff-Cut method as early as 1–2 hours after pouring, before the concrete cracks, calls for a dedicated rim (category blades for fresh concrete). For cutting asphalt, large 350–400 mm blades by Altrad Belle and Cedima mounted on walk-behind saws work best.

Diamond blade sizes — 125, 180, 230, 350 and 400 mm

Diameter is matched to the tool and the cutting depth — a blade reaches into the material by about one third of its diameter, so a 125 mm blade cuts to roughly 40 mm and a 400 mm blade to as much as 130–140 mm. A 22.2 mm bore fits angle grinders, while 25.4 mm fits cut-off saws and concrete saws.

The most popular are 125 mm blades for quick grinder work and 230 mm blades for deeper cuts — both diameters are offered with a blade for every material. Always check the maximum diameter and bore approved by the tool's manufacturer.

Diamond blade dry or wet cutting

Dry cutting is convenient for short jobs with an angle grinder — the blade is cooled by air through its gullets, but needs a pause every 30–60 seconds so the rim does not overheat; segmented and turbo blades for concrete, brick and asphalt are best here, and the drawback is heavy dust. Wet cutting feeds water that cools the sinter, binds the dust and multiplies the life of the blade — it is used for porcelain, clinker and long cuts on saws with a water system. Continuous-rim tile blades work mainly wet, while many segmented concrete blades run in either mode — the permitted mode is marked on the body by the manufacturer. When wet-cutting with a power tool, use a supply protected by a residual-current device.

Frequently asked questions about diamond blades

Why buy diamond blades at NORWIT.PL

We focus on professional blades for construction machines rather than DIY-store substitutes: the range is primarily by Tyrolit, alongside Cedima and Nozar — from 125 mm for grinders to 350–400 mm for cut-off saws and concrete saws. We match the rim type and bond hardness to the material and arrange the range by the surface being cut: for concrete, for fresh concrete, for asphalt, for ceramic blocks, for ceramic tiles, for clinker and for sand-lime blocks. The blades complement the other tools in the cutting, drilling and grinding category. We fulfil orders online, with shipping across the country.