General Information
In this article, we briefly explain how to properly use the TBH 1 diamond drilling machine to achieve clean drillings.
The TBH 1 is a drilling machine that uses a special water adapter to drill wet with diamond drills. Drilling with water is necessary to prevent damage to the drill due to overheating.
The water adapter on the TBH 1 is clamped in the machine's standard built-in 3-jaw chuck. It is important that the adapter sits firmly in the chuck and runs true. The concentricity can be checked, especially at slow speeds, e.g., best when the machine is coasting down. Concentricity is significantly influenced by the quality of the drill chuck. Special quality drill chucks can be retrofitted for better concentricity.
Limits when drilling with the TBH 1
- max. drilling diameter: 12 mm
- max. drilling depth blind hole: approx. 10 to 12 mm
- max. drilling depth through-hole: approx. 20 to 24 mm
For the adapter to work properly, it requires sufficient water pressure of at least 3 bar. A connection to the domestic water supply or a special pump is therefore essential.
For small drills under 2 mm, we recommend the highest speed of the machine: 4,500 rpm.
Drill Bit Construction
The drill bits are two-part, consisting of the drill bit itself and an ejector pin. The function of this ejector pin is to prevent the drill bit from clogging during drilling.
Installing the Drill Bit
Before each installation of the drill bit into the adapter, it must be checked that the ejector pin allows water to flow into the drill bit. This can be checked by pushing the pin into the drill bit. At the stop, a gap must be formed on each side. If this gap is not present, no water will enter the drill bit, and it will be destroyed during drilling. Furthermore, it is important that the pin is slightly longer than the drill bit.
Once this has been checked, the drill bit can be screwed into the M4 thread of the adapter.
After screwing it in, check for concentricity. To do this, switch on the machine briefly. When switching off and as the drill bit coasts down, the concentricity can then be easily checked visually.
Sharpening the Drill Bit
Especially new drill bits or drill bits that no longer drill very well need to be sharpened. The aluminum oxide plate is used for this purpose. Drill several times into the plate to sharpen the drill bit.
Drilling Blind Holes
Preparing the Stone
We recommend pre-treating (sanding) the drilling location so that the drill bit rests flat, and then drilling. After drilling, the stone can be finished by sanding.
Drilling
If the drill bit is sharp, runs true, and sufficient water comes out of the drill tip, then drilling can begin. Secure the stone well on a base with your hand or use a fixture. Carefully guide the drill bit to the stone using the lever. Drilling must be done very sensitively, especially if the surface is strongly curved. Otherwise, the drill bit can quickly "slip" and break. During drilling, water, including abrasion, must flow out of the hole. If no abrasion is visible, the drill bit is dull; sharpen the drill bit. Do not drill the entire depth in one go, but relieve the drill bit several times by retracting it with the lever. This flushes the drill bit clean and prevents it from clogging easily. Drill bits with smaller diameters are less stable than thicker ones and therefore break much more easily during drilling.
Drilling Through-Holes
When drilling through-holes, both sides are drilled to prevent the stone from breaking out. For this, a counterpart with a diameter matching the drill bit is required. The counter pin/counterpart is slightly smaller in diameter than the drill bit. The counterpart is screwed into the magnetic base and must be aligned centrally with the drill bit. Furthermore, the height of the drill bit must also be adjusted. There must be a small gap between the counterpart and the drill bit at the depth stop of the lever.
Finishing the Drilling Process
Switch off the machine and turn off the water supply. Observe the machine's operating instructions.
This is a non-binding description of how we drill. We assume no liability for damages resulting from information in this description.
