Core drills for hard materials
Here are our Diamond core drills for granite, hard porcelain and polymer concrete.
These long lasting barrels can used with your standard drill.
Although they are a little slower than electroplated hole saws, the pros prefer them for their long life.
See instructions for use at bottom of this page (also supplied with core bit).
- Available 6mm to 180mm diameter
- All drill bits have an internal length of 50mm
- Longer lasting - ideal for regular users
Suitable for coring:
- Granite, including bench tops
- Hard porcelain, including tiles
- Polymer concrete
- Electrical and communications cable jointing pits
Fitting:
Up to 29mm, the barrels are fitted with a 12mm hex shank for use with a chuck type drill (adaptors to SDS Plus available at extra charge).
32mm and bigger have a 1/2" BSP female thread, and come with a 12mm hex shank adaptor, a pilot drill bit and a wedge key. For use with a chuck type drill (adaptors to SDS Plus available at extra charge)
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Part Number | Size | Price (each, incl GST) |
CGS6-65 | 6mm | $40 |
CGS8-65 | 8mm | $42 |
CGS6-65 | 10mm | $48 |
CGS12-65 | 12mm | $50 |
CGS16-65 | 16mm | $60 |
CGS19-65 | 19mm | $65 |
CGS22-65 | 22mm | $75 |
CGS25-65 | 25mm | $76 |
CGS29-65 | 29mm | $85 |
CGS32-65 | 32mm | $90 |
CGS35-65 | 35mm | $100 |
CGS38-65 | 38mm | $110 |
CGS48-65 | 48mm | $135 |
CGS51-65 | 51mm | $140 |
CGS54-65 | 54mm | $145 |
CGS57-65 | 57mm | $155 |
CGS60-65 | 60mm | $165 |
CGS64-65 | 64mm | $175 |
CGS70-65 | 70mm | $190 |
CGS75-65 | 75mm | $200 |
CGS90-65 | 90mm | $260 |
CGS95-65 | 95mm | $270 |
CGS115-65 | 115mm | $275 |
CGS117-65 | 117mm | $280 |
CGS165-65 | 165mm | $325 |
CGS180-65 | 180mm | $375 |
Suction Ring Set 38mm & 75mm Water containment for wet drilling. Push the ring down on a flat, smooth horizontal surface and fill with water. $20 incl GST each - ex stock |
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Dymaxion diamond hole enlarger - 35mm diameter. Suitable for most building materials including porcelain and stone. Will also grind irregular shapes and rebates. Used to enlarge an existing hole. 10mm hex shank, 25mm diamond coating. Attach to drill and slowly rotate in anti clockwise direction, using firm pressure. HDEE35 $99 incl GST |
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Instructions:
Use appropriate personal safety equipment - safety glasses, hearing protection etc
If using an electric drill, ensure you use an RCD to prevent electrocution. A battery drill is much safer with water than an electric one, and does generally have slower speeds..
DO NOT use on hammer (percussion) mode.
Even though a pilot drill is included, a simple template or guide will assist your drilling.
Use water to keep the diamonds cool. Or quench drill bit in water. An over heated barrel will cut slower.
Use only medium drilling pressure. The smaller the diameter, the less pressure is needed (otherwise you will damage the drill bit). Drilling is usually slow with these hard materials.
Start drilling slowly and gradually increase the speed, to the recommended speed as indicated below.
Withdraw bit regularly to allow cooling, allow water inside the hole and to clear debris.
Drill with slow speed, medium pressure and lots of water.
See our drill chart below as a guide for drill speeds.
Core bit diameter | 12mm | 25mm | 50mm | 75mm | 90mm |
Fibreglass | 1200rpm | 700rpm | 350rpm | 250rpm | 175rpm |
Glass & china | 800rpm | 500rpm | 250rpm | 160rpm | 125rpm |
Pottery tile & marble | 600rpm | 450rpm | 225rpm | 130rpm | 100rpm |
Porcelain tile | 500rpm | 375rpm | 180rpm | 125rpm | 90rpm |
Granite | 400rpm | 300rpm | 150rpm | 100rpm | 75rpm |
Tips for drilling polymer concrete (used in electrical, data and plumbing pits):
- Pre drill pilot hole or use a template
- Cool the diamond segments by regularly quenching in water
- Avoid excessive drilling pressure
- Wash down the barrel after use to stop slurry building up (dried slurry will slow coring on future holes)
Please see our "Contact Us" page (here) for Australia wide shipping information.
Prices correct as of 1/10/20 but subject to change.
Disclaimer: all the information on this website is provided in good faith and believed to be reliable and accurate at this time. However, the information is provided on the basis that the reader will be solely responsible for assessing the information and its veracity and usefulness. UDT shall in no way be liable, in negligence or howsoever, for any loss sustained or incurred by anyone relying on the information, even if such information is or turns out to be wrong, incomplete, out-of-date or misleading.
Dymaxion HDEM6 Sutton Bunnings
United Diamond Tools
U9, 84 Barberry Way
Bibra Lake
Perth
Western Australia 6163
Telephone: (08) 9434 6878
Mobile: 0419 901 533
Email: sales@udt.com.au