Frequently Asked Questions:


I can't see where I can buy on your website?
Although we will sell most of our products nationally, our website is not automated for purchasing. 
Give us a ring, or send an email. We will send you a written quote, including shipping if required.
If you want to go ahead, you can pay via credit card (in store only), PayPal or direct deposit.
We can then send the goods with a tax invoice and tracking number, usually the same day payment is received.
Please note - Minimum invoice value $50 incl GST

Where is your office?
We are based in Bibra Lake, 20k south of Perth in W.A.. If your are local, feel free to drop in.
See all our contact details, including phone numbers, email, street address, opening hours and a map here.
Look for the UDT sign on the road.
But we will send most of our items anywhere in Australia.

Will you post items to the eastern states or overseas? 
We will post most products nationally. The price for shipping varies on the size and weight of the products you are ordering.
We won't ship machinery as the freight is too expensive. 
We don't ship internationally at all.

Silica Dust:

When workers cut, crush, drill, polish, saw 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 are taken  to limit exposure to dust are in place.
Use a half face respirator or a PAPR (Powered air purifying respirator).
See the WA government's info on silica dust here.


What diamond blade do you recommend? 
What are you cutting?
What with? Brick saw, tile saw, quick cut?
What diameter do you need? What is the centre hole size?
If you answer these questions, we can offer you our recommendations.

How do you use a diamond blade?
It would be almost impossible to outline all operating and safety procedures to suit all saws on all work sites in all conditions.
However, here are a range of factors you need to consider when using diamond tools. Click here to see our tips.
You can also look at the operation manuals of various machines like quick cuts, floor saws, brick saws etc on our website for extra tips here.

How long do diamond blades last for? 
It depends on many factors such as:

  • Bond of the blade you are using
  • Power of your tool you are using it on
  • What material you are cutting
  • Whether you are cutting wet or dry
  • Skill of the operator
  • How deep you are cutting
  • How much force they apply (don't force it) etc .

Generally, short blade life is caused by using a bond which is too soft for the material being cut.
It usually occurs when cutting more abrasive materials such as asphalt, green concrete or limestone.
Wet cutting will also extend the life of a blade compared to dry cutting.

My blade is no longer cutting well - can I resharpen it?
Yes, you can. Chances are it is glazed from cutting hard materials. See how to de glaze it here.

My tiles are chipping when cut - why?
Chipping can be caused by:

  • Wrong blade for the material
  • Material is not securely held in place
  • Check saw  to make sure it is not out of alignment (cutting on a slight angle)
  • Check saw's condition to make sure bearings and rollers do not have any wobble or play
  • Reduce feed rate ie don't push through too fast
  • Insufficient water
  • Blunt blade. See our dressing stones here

Can I cut with your blades dry?
Cutting dry on some materials creates silica dust (respirable crystalline silica), which is very dangerous.
See the W.A. government's info on RCS here.
Also, cutting without coolant will shorten the life of the blade, as well as risk it overheating.

How much do diamond blades cost?
The price of a diamond blade varies depending on the size of the blade, and the quality.
For frequent use and larger jobs, it is better to choose a more expensive Premium Series diamond blade as they will deliver a longer life and a lower cost per linear metre of cutting.
However for occasional use and smaller tasks, it is quite often preferable to choose from the lower priced Trade Series diamond blades.
We also have stocks of budget blades, which are ideal for DIY or tradies with a one off job.
Contact us and we can give you an exact price.

I can get the same blade at half the price elsewhere - how come?
All diamond blades kind of look the same to most people. One main difference is the amount of diamonds they contain.
The difference between a $100 blade and a $300 blade is usually $200 worth of extra diamonds.
Better quality diamond blades have more diamonds, cut faster and last longer.

How deep will my diamond blade cut?
To see how deep a blade will cut, and what speed it should run at, see here.

Will you send your blades Australia wide?
Yes. Blades up to 300mm/12" (around 1.6kg) will fit into a large post bag.
Our 350mm/14" and 400mm/16" blades will fit into a extra large post bag. They can hold 1 x 16" blade (2.6kg) plus some smaller blades, or 2 x 14" blades (2 x 2kg).
Post bag prices are here.

Can I use a diamond blade on my circular saw?
Cutting dry with a diamond blade on some materials creates silica dust (respirable crystalline silica), which is very dangerous.
Also, cutting without coolant will shorten the life of the blade, as well as risk it overheating.
Your saw is not designed for this type of cutting, so overall we don't recommend this.
However, some customers only have one cut, and choose to use their saw.
We have limited diamond blades to suit circular saws, so need to know your blade diameter, centre hole size and material you wish to cut

Core Drills:

How long will coring take?
You are not drilling a hole, you are grinding it. So it will take longer than using an SDS percussion type drill bit.
It depends on many factors such as the diameter of the drill bit, the depth you need to core to, the power of your drill, the hardness of the material etc. But do  allow extra time.

Can I use a concrete barrel on limestone, asphalt or green concrete?
Limestone/asphalt and concrete barrels are not really interchangeable. But on  a one off hole, a concrete barrel may do the job, but it will wear faster and may bind up.
Limestone segments are harder because of the abrasive nature.
They are also wider to allow for an increased barrel clearance. This is because limestone dust is coarser than concrete dust, and will clog the barrel to hole clearance, causing binding.
Limestone barrels will work on softer concrete, but struggle with the steel reinforcement.

Will you send your core barrels Australia wide?
Core barrels (even the smaller sizes) are generally over 400mm long, so need to go in a extra large bag (up to about 100mm should fit in a 5kg bag, maybe even two depending on the diameter).
So grab a couple (or some diamond blades) and reduce the price of freight per barrel. An 18mm core barrel (1/2" thread) is 0.5kg, while the 1 ¼" bits start at 0.8kg.
We are happy to send you a quote. Air bag prices are here.

My core barrel is no longer coring well - can I resharpen it?
Yes, you can. Chances are it is glazed from cutting hard materials. Redress the bit by reducing the water by half for a few minutes, until the water exiting the hole is really muddy.
A bit of Ajax or clean builders sand down the hole can also have the same effect - run the drill at a slower speed, with reduced downwards pressure, so that an abrasive paste forms that will sharpen the segments . Or drill into an abrasive material like limestone, a cinder block or similar. Other operators swear by turning the barrel upside down and giving each segment a firm whack on the cutting edge with a piece of reo bar.
See how to de glaze it here.

What speed should I run this core barrel at?
The bigger the core barrel diameter, the slower it has to run. See our core speed chart here.

How long do core barrels last for? 
It depends on many factors such as:

  • Bond of the barrel you are using
  • Power of the drill you are using it on
  • Speed of drill
  • What material you are cutting
  • How much water you are using
  • Skill of the operator
  • How deep you are cutting
  • How much force they apply (don't force it) etc

Generally, short barrel life is caused by using a bond which is too soft for the material being cut.
It usually occurs when coring more abrasive materials such as asphalt, green concrete or limestone.
Too little will cause the barrel to wear quickly, whereas too much may cause barrel to glaze up..

I am trying to core laterite, and it is really hard and slow to core. What do you have for it?
Because laterite is natural, it's composition varies. Sometimes a standard limestone barrel will be sufficient  but most times a specialist barrel is required. Laterite is generally very hard and slow to core. We sell these in 127mm diameter, the most common size for fencers.
Tips - Ensure operator uses a correctly sized core drill and stand (that is bolted down firmly), at correct speed to suit the barrel diameter.
Do not force the barrel - it will not drill faster!
Do not use too much water.
Clean loose debris from hole regularly.
Note - When drilling laterite the bit may glaze up and need redressing. Do this by reducing the water by half for a few minutes, or by drilling into an abrasive material like limestone, a cinder block or similar. A bit of Ajax or builders sand down the hole can also have the same effect.


How do I fix this scratches/stains/damage on this surface?
We are mainly involved with the construction industry.
But our suppliers also manufacture polishing pads, so we import and sell those as well.
We have no real experience with polishing in domestic applications, and especially stain removal.
All the info on the website was provided by the manufacturers, or from customer feedback.
Perhaps your supplier or installer could assist with advice?
Most installers have a range of pads and can try them until the best result is achieved.

See operating instructions on hand pads here, wet polishing pads here and dry polishing pads here .

Can I use your grinding polishing pads to remove scratches from polished porcelain tiles?
Our polishing pads are for use on natural stones like marble and granite, but also ceramic, concrete and engineered stones.  
The diamond hand polishing pads can be used on small areas, and the diamond resin polishing pads are for use with a polisher for larger areas.
Note - Our diamond resin polishing pads can only be used at a maximum speed of 4500RPM, so use a variable speed angle grinder or a polisher. A fixed speed angle grinder is usually twice as fast as recommended, and pads will deteriorate quickly.
Polished porcelain tiles may have a glossy, polished glaze, ie they are not uniform all the way through like granite, marble etc. Other tiles may have a lacquer finish. Rubbing in one spot (either by hand or with a grinder) may leave an area of hazy finish, ie not the usual gloss finish as the rest of the tile. 
If the scratches are minor, try baking soda, toothpaste, brass polish or Barkeepers Friend to manually remove porcelain scratches. Thoroughly clean the scratch, then apply over the length of the scratch. Buff the scratches with a soft, damp cloth.  After it is thoroughly clean and dry, some people have success sealing the tile by applying car wax to bring up the gloss again. This manual method needs a lot of effort (elbow grease!).
If you wanted to try our pads, we suggest you start with a 3000 grit. If that did not remove the scratches,  try a 1500 grit, finishing off with the 3000 grit. You may need to go as low as 800 grit. Always try first in a inconspicuous spot, and see instructions on each page.

What is exposed aggregate?
Exposed aggregate is a decorative finish that is stylish, durable and easy to maintain. The look is achieved at time of the concrete pour.
Once the concrete has set, the surface is pressure washed to expose the aggregate (rock) underneath.

What is honed concrete?
Honed concrete is like exposed aggregate, but has a smoother matt finish. It is not as polished as polished concrete (see next).
After laying, the concrete needs to cure for some time - a general rule is the concrete should be cured for 28 days before you start
Once set, you will need to remove the top layer of concrete to expose the decorative stone aggregates within the mix.
Use our diamond resin polishing pads to achieve the finish the you want.

What is polished concrete?
Polished concrete is a good looking and durable finish that is obtained by polishing a concrete surface with our diamond resin polishing pads until a glossy surface is achieved.

Polished concrete is made by grinding and polishing your concrete until it reaches the desired look.
Next, a process known as hardening occurs, where the use of a hardener penetrates the concrete, creating a chemical reaction to help harden and dust proof the surface.
During concrete polishing, the surface is processed through a series of steps (in general a minimum of 6 grinding steps are completed for it to be considered polished concrete) utilising progressively finer diamond resin polishing pads.

What is "Grind and seal" concrete?
This is where the concrete substrate is ground back (usually to #200 – #400 grit) and then coated with either a polyurethane or epoxy topical coating to give the look of polished concrete without the labour intensive grinding and polishing.


I have lost my machine's operating manual - can you send me one?
All the operating and spare parts manuals we have can be downloaded from here.
You can download our core drilling booklet at the bottom of this page.

What is the correct ratio for making up two stroke oil?
Always consult your saw's handbook first for recommendations.
If you make a fuel/oil mix with too much oil, your engine may be hard to start or run, carbon can buildup on engine internals, it will blow smoke and generally perform poorly.
Too little oil in your mix can cause permanent and expensive internal damage and overheating.
The biggest problem we see are incorrect fuel/oil mixes made up on site. For example, some 5 litre fuel cans will hold 5.5 litres. When 100ml of oil is added, a few mls of oil can be left behind. The ratio of oil is now too low (almost 60:1). It will not affect the engine immediately, but continual use at this ratio will reduce compression and making starting harder. Similarly, using a cap full of oil per tank of fuel is simply too inaccurate.
Husqvarna generally recommend 50:1 on their saws (100ml per 5l or 20ml per litre).
Guarda recommend 40:1 (125ml per 5l or 25ml per litre) in their saws.
We are happy to recommend 40:1 for Husqvarna saws as well, which is 125ml per 5l or 25ml per litre. 
See Husqvarna's forestry page for some great tips on how to mix two stroke fuel  here.

My two stroke cut quick won't start - what do I do?
Firstly, make sure the on/off switch is in the on position.
If you haven't used the machine for a while, you may need to replace the old fuel with fresh two stroke fuel.
If compression is low (resistance when pulling the starter rope is less than normal), then it is a job for a mechanic (likely an engine rebuild!).
Similarly, if the blade turns when pull starting, it is another job for your mechanic (clutch needs attention).
But if it is just flooded, you can try one of these options:
 - Remove the spark plug, pull the starter rope quite a few times to clear the fuel, then reassemble and try again. Use correct starting procedure (see operation manuals here)
 - Lock the throttle on full (use tape or a cable tie), no choke and pull repeatedly until it starts. You may need quite a few pulls to clear the fuel, and when it does start, it will be at full revs.
 - Alternatively, Rapid Start, Aerostart etc can be spayed sparingly into the air intake (take top cover off) or exhaust outlet. Use without choke. Refer to their instructions. Again, use sparingly.
We have to repair broken pull starters and ropes frequently because saws won't start.

Will you ship machinery to the Eastern States or overseas?
No, as freight is too expensive. Let us know what you are chasing, and we can try to point you to a local supplier in your state.

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We have provide a lot of information on this website, and it done so 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.


United Diamond Tools

U9, 84 Barberry Way
Bibra Lake
Western Australia 6163

Telephone: (08) 9434 6878