Electroplated Diamond Drill Bits

Please note - this full range is not available, and is being replaced by Bordo's bits.
See them here.

Ideal for trades people, handy people and DIY for cutting glass, china, fibreglass, pottery, tiles (marble, porcelain, granite, travertine etc), fibre cement, poly carbonates, polymer concrete and more. Our HDEM bits use a finer diamond than the ones you find in big hardware stores, so will cut better. See instructions for use at bottom of this page (also supplied with core bit).

Core drilling depth of 65mm.

(For longer lasting, professional series bits, see the seperate page on "Granite, Porcelain and Polymer Concrete (CGS) core bits" page here. As a comparison, a skilled operator can get up to 40 holes 10mm deep with the HDEM. They should be able to get 150 holes out of the CGS, although they will core slower.)

Supplied with a hex shank, so will fit most drills with a chuck (not SDSPlus or Max).
These are to be used in rotary mode only ie not hammer drill.

These bits can be purchased individually (6 - 108mm).
Or we stock the HDEMK8 kit  -  8 Piece kit with drill guide (4, 5, 6, 7, 8, 10 & 12mm bits). 
$95 incl GST

Part No	Diameter	Sell Price	Part No	Diameter	Sell Price	Part No	Diameter	Sell Price
HDEM6	6mm	$30	HDEM35	35mm	$72	HDEM75	75mm	$167
HDEM7	7mm	$31	HDEM37	37mm	$76	HDEM77	77mm	$175
HDEM8	8mm	$31	HDEM42	42mm	$87	HDEM82	82mm	$187
HDEM10	10mm	$31	HDEM44	44mm	$92	HDEM85	85mm	$195
HDEM12	12mm	$31	HDEM50	50mm	$105	HDEM86	86mm	$200
HDEM13	13mm	$32	HDEM51	51mm	$106	HDEM88	88mm	$208
HDEM16	16mm	$35	HDEM52	52mm	$110	HDEM89	89mm	$213
HDEM19	NLA	NLA	HDEM60	60mm	$128	HDEM90	90mm	$220
HDEM20	20mm	$42	HDEM63	63mm	$136	HDEM95	95mm	$237
HDEM25	25mm	$99	HDEM67	67mm	$145	HDEM105	105mm	$242
HDEM32	32mm	$65	HDME69	69mm	$151

Pilot bit for this range - $8 incl GST (a pilot drill is included with all barrels 19mm and above)

Please note - this full range is not available, and is being replaced by Bordo's bits.
See them here.

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

Dymaxion diamond hole enlarger - 35mm diameter.  Used to enlarge an existing hole. Suitable for most building materials including porcelain and stone.  Will also grind irregular shapes and rebates. 10mm hex shank, 25mm diamond coating. Attach to drill and slowly rotate in anti clockwise direction, using firm pressure.  HDEE35 $99 incl GST

Instructions for using electroplated core bits:

Fit the hex shank fully into the drill chuck and tighten.

Use appropriate personal safety equipment - safety glasses, hearing protection etc

Clamp the material to be drilled firmly.
Never hold the material with one hand while drilling with the other!

Use only medium drilling pressure.
The smaller the diameter, the less pressure is needed (otherwise you will damage the core bit).

Use slow speed drills. A battery drill is much safer with water than an electric one. If using an electric drill, ensure you use an RCD to prevent electrocution.

Apply plenty of water.  Some objects can be barely immersed in water (beware water in the drill).
Or try one of our water suction ring sets - see here
The drill bit should never get above 50° C - too hot to touch.
Tip: Cut a sponge to roughly fit inside the barrel, and make sure it gets wet when the barrel is cooled in water.
This will provide cooling as the barrel spins

Withdraw bit regularly to allow cooling, allow water inside the hole and to clear debris.

A pilot drill bit is provided on larger diameter bits, but a simple template guide is just as fast. Or use the drill guides, below.

Be aware that porcelain and glass may fracture and these can be very sharp.

Core bit damage will occur if:
 - the drill bit gets too hot to touch
 - drill speed is too high
 - insufficient cooling water
The diamond crown will turn blue and the diamonds will strip off. This is not warranty, so follow these guidelines.

Check our drill chart below for recommended speed.

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

Drill Guides: Drilling holes in stone tiles or other hard, smooth surfaces is often hard to start, especially when working with the lubricants necessary for diamond hole cutters/drill bits. This drilling guide is designed to hold your bit steady so you can start the hole in the right spot without slipping or sliding. Both use a 120mm suction cup

Plastic (red): 8-80mm, with water injection point (for lubrication when drilling) $15

Steel (blue): 8mm to 54 mm $25

(Pictures show two guides in each photo - prices are for 1 each)

Silica dust - when workers cut, saw, crush, drill, polish or grind products that contain silica, particles are created, which are one-hundredth of the size of a grain of sand. These can get  stuck deep in the lungs. 
Ensure precautions to limit exposure to dust are in place.
See the WA government's info on silica dust here.

Please see our "Contact Us" page (here) for Australia wide shipping information.

Prices correct as of 1/10/24 but subject to change.

Disclaimer: 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