What is this drill bit suitable for?
With this drill bit, you can drill small holes from 0.8 mm up to a maximum of 8 mm in diameter. The drill bit is suitable for softer stones as well as for particularly hard ones like agate or jasper.
Recommended Diameters
For gluing in pin bails or clips, we recommend a diameter of 1.2 mm. For leather cords, there are two options. For single threading, the next larger drill bit based on the diameter of the leather cord is sufficient. For double threading, the drill bit must be approximately twice the size of the leather cord and slightly larger.
Tip for leather cords: To make the leather cord last longer, we recommend countersinking the hole. This protects the leather cord and prevents it from wearing through as quickly.
Construction of the Drill Bit's Diamond Coating
This drill bit is a multi-layer electroplated drill bit, meaning that the drill bit is diamond-coated throughout its entire volume. The drill bit is always designed as a core drill.
What Shank Does This Drill Bit Have?
This drill bit is available with an M4 fine thread shank for the TBH1 and TBH2 machines or spindle set. However, there is also a shank with a cylindrical shaft.
Which Machine Do I Need?
There are special drilling machines for wet drilling, such as the TBH1 or TBH2. For using these drill bits, there is also the drilling spindle set, but this requires a drilling machine with good concentricity. Drill bits with a cylindrical shaft can be used with handpiece machines or hanging motors.
Important Technical Details
For the drill bit to function correctly, the following technical details must be observed:
- The ejector pin must be slightly longer than the drill bit. It should protrude by approx. 0.5 mm.
- The ejector pin must not block the water flow.
- The drill bit must always be sharpened before its first use or if it no longer works correctly.
- Pay attention to the concentricity of the drill bit in the machine.
Sharpening Drill Bits
Sharpening a drill bit is an important point. Sharpening is done using a special sharpening stone made of, for example, aluminum oxide. To sharpen, simply drill into the sharpening stone 2 to 3 times. New or dull drill bits must be sharpened before use. You will notice the difference!
Common Mistakes
- Drilling without water (turn on water)
- Drilling with dull drill bits (sharpen drill bits)
- Too low speed (Ø 1.2 mm min. 2500 rpm)
- Drill bit clogged (clean drill bit with a needle)
- Applying the drill bit at an angle (The drill bit breaks easily under lateral load)
