What do I need to consider when core drilling, how do I drill optimally?
Question:
What do I need to consider when core drilling, how do I drill optimally?
Answer:
When working with magnetic core drills, special care must be taken to maximize the service life of the tools and to ensure the safety and precision of the drill holes.
- Selecting the right core drill.
If an unsuitable drill bit is used, this can lead to insufficient drilling performance or even tool breakage.
- Storing and transporting the core drill
The core drill itself should always be handled with care. It should only be transported and stored in the packaging provided to prevent damage. Even a slight knock can cause
the sensitive cutting edges to break.
- Ensure that the machine is stable.
The workpiece surface must be even, clean and at least 12 mm thick. Information on material thickness can be found in the operating instructions for the respective machine.
If the material is too thin, the magnetic holding force of the machine may not be sufficient. As a result, the machine may become misaligned during the drilling process, which
can lead to chipping of the cutting edges or even to the drill bit breaking off at the shank.
- Use a centering pin.
This ensures that the drill core is reliably ejected and the coolant supply is free or switched off.
- Ensure the required coolant supply.
The coolant is delivered directly to the drill tip by the integrated internal cooling lubrication. Gravity lubrication does not work for overhead or horizontal drilling.
It must be lubricated with a cutting spray or pump spray. The internal cooling of the drill bit ensures that the cutting edges do not overheat, become blunt or break out.
- Make sure you select the correct gear speed.
The speed is set depending on the desired drill diameter: Small diameters - high speed. Large diameters - low speed. Start the drilling process with the drill motor switch.
- Position the drill carefully and drill through in one go if possible.
- Overlapping holes should be avoided, as the cutting edges can hook into the first hole. When re-engaging, small impacts occur which damage the cutting edges.
- Drilling close to weld seams or cuts made by cutting torches is also problematic. The high temperatures generated there can change the structure of the material and
significantly accelerate the wear of the core drill.
- Do not switch off the machine during the drilling process,
Switching off the machine in the drill hole must be avoided.
Excessive force is exerted on the cutting edges when restarting.
Always ensure that the core drill is moved out of the drill hole before the machine is switched off
- From a cutting depth of 30 millimetres, it can be advantageous to briefly interrupt the drill feed and retract the core drill slightly.
This ensures safe chip removal. After breaking through the material, remove the core drill from the drill hole with the drill motor running.
- Before retracting the drill bit from an unfinished hole, allow the machine to run briefly on the bottom of the hole without removing chips.
This will break the chips at the bottom of the hole.
- Only remove chips with the supplied chip hook. -> Risk of injury.