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Let’s Talk Diamond Core Drill Bits

Let’s Talk Diamond Core Drill Bits

How they are measured?
We construct our bits for accuracy on the outer diameter (OD), therefore the measurement given is for the outer diameter.


How are they made?
  • Our diamond core drill bits are similar in function to a standard, sintered drill bit, where the diamonds are completely interspersed throughout the metal, however, our proprietary production process produces a stronger bit, with a longer life span. Our drill bits can yield 500 to 800 holes per bit!!
  • Most sintered bits are produced by melting diamonds and metal power together. Our manufacturing process pulls the metal over a diamond matrix, which results in a higher concentration of diamond for superior cutting power.
  • Additionally, each bit is grinded between peaks to allow for a smaller abrasion area with high rotation precision. 


What is our self-centering system that allows you to avoid punch out chipping?

We've developed a great solution for "punch out".  When you drill through a stone from one side, the opening at the other end most often chips or fractures. This is called "punch out". The way to solve this is to drill halfway from one side then flip the stone over and finish the hole from the other side. The challenge is aligning the holes so that they meet in the middle and remain centered in your stone. We have developed a self-centering system that automatically aligns the holes and ensures a centered hole every time.

The key to this system in the counter part, which is a post that has the same diameter as your drill bit. This counter part is aligned under the drill bit in the magnetic base, and the item to be drilled is then laid on the counter part. You drill halfway through the stone then flip the stone over and put the hole onto the post. Your stone in now perfectly centered and ready to drill through the other half. The drill will meet in the center every time. 


Recovering the core from the bit and what to expect regarding the diameter of the core.

We regularly sell our diamond core drill bits to folks looking to recover the core from the bit. We have found that on average, the inner diameter (ID) of the bit is 1 mm less than the OD. Therefore an 8.0 mm drill bit will usually create a core with a diameter of 7.0 mm.

Of note: Because we do not produce for ID accuracy, you may find some variation. Depending on your tolerance levels, we have a simple work-around. We make custom bits in 0.1 mm increments so we should be able to get close to an inner diameter that you need by ordering the outer diameter accordingly. Custom bits usually take 4 to 6 weeks to make.

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