Diamond Saw Blades – Types, Wear, and Sharpening
Content of the Article
In this article, we describe the different types of diamond saw blades, why they become dull with use, and how they can be resharpened.
Introduction
Most people who have worked with a sawing machine are familiar with the problem: the saw cuts very slowly, and cutting through a stone takes a very long time. Often it is assumed that there is a defect in the machine – however, in most cases, a dull saw blade is the cause.
Why do diamond saw blades become dull?
Diamond saw blades cut by protruding diamonds removing material. This is not a classic sawing process like with wood, where geometrically defined teeth cut. Rather, it is an abrasive process with a geometrically undefined tooth shape, where the protruding diamond acts as a “tooth”.
For a diamond saw blade to cut, the diamonds must protrude from the bonding material. If this is not the case, the blade merely glides over the material to be cut without effectively cutting.
Types of Diamond Saw Blades
The diamonds are fixed in a bonding material. Depending on the type of this bond, different types of diamond saw blades are distinguished:
- Saw blades with mechanical bonding
- Saw blades with metallic bonding
- Saw blades with ceramic bonding
- Saw blades with plastic bonding
In the lapidary field, usually the first two types are used.
Saw blades with mechanical bonding
In saw blades with mechanical bonding, the diamond grit is mechanically fixed on the carrier – usually a steel sheet. For this purpose, special grooves are made in the sheet, into which the diamonds are inserted. Subsequently, the grooves are pressed together, thereby securely holding the diamonds.
Saw blades with metallic bonding
Saw blades with metallic bonding are also called sintered saw blades. Depending on the composition of the metal alloy, there are softer and harder bonds.
Rule of thumb:
- Soft material → hard metallic bond
- Hard material → soft metallic bond
This allows these saw blades to be specifically tailored to certain materials. For this reason, they often cut certain material types particularly well. A common metal alloy, for example, is bronze bonding.
How are diamond saw blades sharpened?
Basically, there are two ways to resharpen a diamond saw blade:
- when installed
- dismantled on a special machine
In practice, sharpening when installed is usually applied. For this, a so-called dressing stone is used.
Dressing Stones
Dressing stones consist of different materials, for example:
- Aluminum oxide
- Silicon carbide
- Dressing stones with special resin bonding
The purpose of the dressing stone is always the same: the bonding material is abraded so that new, "fresh" diamonds are exposed.
The Sharpening Process
The sharpening process works optimally in dry operation. If this is not possible, sharpening can also be done in wet operation.
For sharpening, cut into the dressing stone several times. Some experts recommend switching off the machine while cutting into it and letting the saw blade run out in the dressing stone.
Depending on the degree of wear of the saw blade, this process must be repeated several times.
How to recognize a sharp saw blade?
- A hissing sound is produced when cutting.
- The sawing process takes significantly less time.
- Significantly less contact pressure is required.
Important Notes
If a saw blade no longer cuts well, you should never work with increased pressure. This often leads to the blade no longer cutting straight but rather curving. Furthermore, the lifespan of the saw blade is significantly reduced.
Safety Notice
Always wear personal protective equipment (PPE) when sharpening, especially safety glasses and a dust mask.
This article is for support only and does not replace original operating instructions. No liability is assumed for damages resulting from the application of these instructions.
