Silverline 199883 TCT Core Drill Bit 110 mm

Product Information

Corded power drill with safety clutch and variable speed ideal for use with a core drill How Fast Should you Drill When Using Core Bits?

Most domestic use diamond core cutters will always have a removable guiding drill bit which acts as a pilot hole to guide the core drill.For example, smaller holes up to 30mm in diameter can be drilled at up to around 3000 rpm whereas large holes around 400mm should be drilled at speeds as low as 300rpm. Generally, the guide or pilot bit is just used to get you started and keep the actual core bit in position whilst cutting into the surface of the wall. With the drill held straight and true, keep drilling, stopping regularly and withdrawing the bit from the hole to allow it to cool down. When withdrawing a core bit from a hole ensure that it is still rotating.

In general, a corded drill is the best to go for as it will produce power at a more constant rate, but if funds are available, the more expensive and higher quality cordless drills (minimum 24v) from brands such as DeWalt, Makita, Milwaukee etc should provide more than enough grunt.Due to the amount of heat created during the drilling process it is necessary to keep diamond core bits as cool as possible to prevent unnecessary damage to the cutting teeth to a minimum. If the surface of the cutting teeth are subjected to too much heat the metal encasing them melts covering the diamonds and reducing cutting efficiency. If this happens the drill bit then needs to be “redressed” to expose the diamonds once more. The best tool to use for this is a cable and pipe detector. You simply pass it over the surface of the wall and if any items such as these are found, lights and/or a buzzer indicate their presence. How to Drill a Hole using a Core Drill When hiring or buying a core bit always make sure you have the correct size and type of arbor for not only the core bit your are using but also for the type of drill you have e.g. SDS, spline, straight shank etc. There are many core drill sizes and generally each size is manufactured to represent the size of a commonly used pipe, cable or duct so that once the hole is drilled, the object in question passes through with ease.

Keep drilling until the core drill teeth hit the surface of the wall. You will feel them bite once they do. You can never take it for granted that work hasn’t been done by someone else in this area before and it has not been recorded. As we have briefly touched on, a core drill is a drill bit which cuts large holes through masonry and concrete removing the centre part of the hole (core) as it drills and cuts its way through. Although it is not recommended, many use hammer action with these drill bits to increase their cutting speed and ability. This will ultimately wear the core bit out much faster, but as they are generally cheap this is not often seen as a major concern.

What Type of Power Drill do you Need for Core Drilling?

In the majority of domestic cases the largest hole you will need to drill will probably be around 6 inches in diameter through a standard cavity wall which will be around 300mm in depth. For anything up to this size a dry cutting diamond core bit will be more than up to the job.