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Instructions on How to Use Diamond Drill Bits – Keeping Cool and On Target

Drilax Diamond Hole Saw Diamond Drill Bit

How to Use Diamond Drill Bits

Keeping Diamond Hole Saws Cool and On Target

How to Use Diamond Hole Saw

How to Use Diamond Drill Bits

In this post, we will try to give you some basic DIY information on how to use diamond drill bits and How to Use Diamond Hole Saws. Generally speaking, diamond drill bits – diamond hole saws are used on brittle materials such as ceramics, porcelain, glass, granite, marble, quartz, tiles, etc. To see our selection of diamond drill bits please visit our store. You can also visit our Amazon Store

What is a diamond drill bit?

We usually start giving instructions and tips about tools before we address a simple question: What is a diamond drill bit? A diamond drill bit is nickel coated metal circular piece (a tube) with a shank for the drill. The rim of the circular tube is coated with artificial diamond abrasive particles. And these diamond abrasive particles do all the work. Although these tools are called drill bits, the main working principle is the grinding action. Diamond abrasive particles adhered to the rim of the diamond hole saw grinds away the material in a circle and a hole is formed by removing a core plug. The first image below shows how the grinding away starts.

5/16 inch Diamond Drill Bit
What is a diamond drill bit
Grinding Action After 30 Seconds


Removal of a core plug of quartz
Completed Hole in Quartz


How long does a diamond drill bit last?

One of the main differences between a regular drill bit and diamond drill bits: you can not sharpen diamond drill bits. Diamond drill bits will last as long as you keep the diamond abrasive particles on the rim of the bit. There are two kinds of diamond drill bits:

1- Electroplated Diamond Drill Bits

These types of diamond drill bits are often considered light to medium-duty tools. The diamond abrasive particles adhere to the rim with a metallic bond. If the tools are overused or abused, the increased temperature will cause the bond to break. The diamond abrasives will be gone and the diamond hole saw rim will have no grinding action left. You can not sharpen or reattach the diamond particles. If the diamond drill bit is used properly, it will last a long time and will serve very well. Please see our posts on how to use diamond drill bits keeping them cool and on target. One of our previous customers posted a comparison of two Drilax diamond drill bits, one of the unused and the other used 4 times.

While using our standard diamond drill bits, it’s important to recognize these basic principles. In a product review, one of our customers says:

“Great product, excellent value!
Purchased this for a couple of holes for installing floor tile… nothing fancy, just your typical ceramic tile. Use it wet and dry with my 18volt drill… did the trick with ease. Trade advice, let the tool and bit do the work, no need to put that extra muscle on it.”
Here the product in question is our 1-1/4 inch Diamond Drill Bit.


2- Heavy Duty Sintered Diamond Drill Bits

The heavy-duty type diamond drill bits, diamond hole saws have the diamond abrasives embedded in the metal itself. There are no visible diamond particles on the rim. These types of tools will last hundreds of times and they could be used dry. However, we always suggest using water for better performance. In this picture below, you can see one of our heavy-duty diamond hole saw for concrete or masonry drilling.

4 inch Diameter Heavy Duty Diamond Hole Saw
4-inch Diameter Heavy Duty Diamond Hole Saw for Concrete, Bricks, Cinder Blocks


These Drilax Heavy Duty Concrete Hole Saws can be used with regular drills because they have standard 3/8 shanks for standard chucks. One of our customers has posted a few pictures of the 4-inch holes they drilled with Drilax Heavy Duty 4 inch Diamond Hole Saw.  He was very happy with the results.

4 inch Diamond Hole Saw

2 inch Diamond Hole Saw for Concrete


In addition to these models, we also have Professional Series Heavy – Duty Diamond Hole Saws for very deep drilling.

Drilax Concrete Diamond Hole saw

Using water for cooling the tool is important. Here are ways to keep the tool to prevent overheating:

Build a Small Water Dam

Plumbers putty is great for building a mini water dam around the hole area.

Water Dam Putty

Positioning the diamond drill bit can be a challenge and it is an important part of how to use diamond drill bits. Here are some of the ways you can start drilling the hole:

Start the Hole At an Angle

Pilots drill bits are not useful when it comes to drilling brittle materials. To drill holes in porcelain or ceramic tile, glass or granite,  start the hole at an angle and slowly work it straight.

Starting Diamond Hole Saw Drilling

Drilling Porcelain Tiles

Here is a close up for “starting the diamond hole saw at an angle”

How to use diamond drill bits

You can go up straight, once you for a C Slot cut in the material:

Some of our products such as 3 inch, 4 inch, and 4-1/2 inch Drilax Diamond Hole Saws come with a locator template.

Diamond hole saws are known for their efficiency and precision, but they do require proper cooling to prevent overheating. To maintain the longevity of your tool and achieve the best results, it is essential to follow the cooling guidelines. We have also included a drill template that serves a dual purpose of holding the hole saw in position and facilitating the cooling process with water.

If you are drilling a hole on a horizontal surface, please fill the drill template with water as instructed. This setup assumes a regular application where water can be contained within the template, providing continuous cooling to the hole saw. The water helps dissipate heat and prevents the tool from getting too hot during operation.

However, if you are drilling a hole in a wall or any other vertical surface, the drill template can still be used as a positioning guide. In this case, please note that the water cannot be held within the template due to the orientation. Instead, we recommend dipping the tip of the tool into water every 5-10 seconds. This intermittent cooling method ensures that the tool remains at an optimal temperature, reducing the risk of overheating.

By following these guidelines, you will maintain the effectiveness and durability of your diamond hole saw, allowing you to achieve accurate and clean cuts in various applications.


As an alternative, you can use one of our sets that come with a foam insert guide.

Diamond hole saw set with foam insert guide

You can also use our adjustable guide for positioning the diamond hole saw. You can see our instructions on how to use diamond drill bits with guides here. One of the helpful tips about using our guide is this: run your drill in the reverse direction. Diamond hole saws will work in either direction, by running the drill in reverse you will make sure thumb screws never get lose.

Drilax Diamond Hole Saw Guide


1- This is a guide for diamond hole saws and its main function is to get the hole started on the right spot. Once the hole has started, the diamond hole saw will continue drilling. You will not have to use the guide all the way through the hole. After 1 minute of drilling, you can remove the guide. Guide and the ball bearings do not have to there for the whole duration of the process.

2- Diamond hole saw applications require water for cooling. Thanks to this water, the dust turns into mud. If water is used, there should not be any dust to contaminate the work area.

3- Diamond hole saws will cut in either direction. You can run your drill counterclockwise. If you use the drill counterclockwise, it will tighten all the nuts as you go. You won’t need to worry about loose nuts and bolts.

4- This is a very versatile product and you can use it with or without the second plate. If you remove the plate, the V shape notch will be enough to start the hole. Once again, you do not need the guide for the whole duration of the drilling.

Drilax Diamond Hole Saw Guide Kitchen

Perfect Hole in Tile

This is how you can achieve results with Drilax Diamond Drill Bits.

Drilax Diamond Hole Saw Set Guide


Using Diamond Drill Bits for Jewelry Making

Diamond Drill Bits for Stone Jewelry:

We also carry very small diamond drill bits with diameters of 1mm, 1.5mm, 2mm, 2,5mm, and 3mm. These are mostly used by artists for drilling holes in precious stones, seashells, sea glass, rocks, beads, etc.

Twist Diamond Drill Bit Set
Twist Diamond Drill Bit Set for Jewelry Making

Sea Glass Drilling
Drilling Holes in Sea Glass


Over the years, we have gathered these suggestions on how to drill sea glass to make jewelry:

DIY TIP 1: A high-speed tool works best, speed is important, not pressure.

DIY TIP 2: Cooling is important. Keep the hole you’re cutting constantly bathed in water. You can feed water to the drilling spot, always keeping it wet. Or you can submerge the whole piece in water in a plastic container. DO NOT SUBMERGE any electric tools. 

DIY TIP 3: Start at an angle, use MINIMAL pressure on the drill, just enough to let the diamond abrasive grind away the material. Once you make the initial mark, go upright vertical. Using pressure will just damage the drill bit and not get you there any sooner.

DIY TIP 4: You should clean the tip of the bit with water every 10-15 seconds.

Along with these tips, practice is required. There are many bits in the case, a few of them may be imperfect. Just try a different one. If you received too many imperfect bits, just let us know and we will replace them for you.

One of our recent clients has posted this picture and wrote about her experience with Drilax diamond drills bit for jewelry:

“I needed bits that could drill through porcelain and these are PERFECT!
I place the porcelain on a wet sponge in a small Tupperware container to make sure the bit is always wet and it takes about a minute to drill completely through. I’M SO HAPPY”

diamond drill bit for jewelry

Tub Drain Project

Using one of the larger Drilax Diamond Holes, this project for tub drain is completed. The small hole is for water pipes.

Tub Drain Hole Tiles

How much are diamond drill bits?

We have a very wide range of sizes, depth of cut, and types of tools. The average price of a diamond drill bit if purchases in a set could be as low as 2 dollars. We also have monster size diamond drill bit holes saws with 6, 7, 7-1/2, 8 inches diameter, their prices can be over 100 dollars.

How to make lamps out of wine bottles?

This is one of the questions we receive frequently especially during the holiday seasons. The question is concerned with “drilling holes in glass bottles” for different decorating ideas.

The recommended tool for this task is a diamond drill bit.  Most people find it hard to believe but you can actually drill very clean holes in glass bottles or blocks to make lamps or other decorations. The holes are mostly needed to run the electric cables or bulbs.

There have been some out of date discussions on the internet that will recommend regular drill bits or types of carbide drill bits for glass.  Diamond drill bits will produce the best results. Some people do not know about the new technology diamond drill bits. For more information and instructions on how to use diamond drill bits, please visit our instructions page.

We always urge you to practice safety and patience. You can be successful if you follow the basic tips.

Pay attention to these when drilling holes in glass bottles:

  • It is a good idea to practice on some junk bottles before doing the actual projects.
  • AT ALL TIMES wear safety goggles and protective thick gloves.
  • Please do NOT push the drill bit hard, it’s the grinding action that will do the work.
  • Be patient and go slow.
  • Keep the tools cool with water – do NOT submerge any electric tools in water.

You can prefer the side of the bottle and not the bottom. Bottoms are extra thick for drilling.

Tools and Materials

  • You can use a hand drill (electric or cordless) or you can use a drill press.
  • You need some kind of a cushion-like a thick table cloth or folded towel between the bottle and work surface.
  • Some types of protective gloves, like leather or such.
  • Water for cooling.
  • Drilax diamond drill bits

There are two areas of focus here:

  1. Keeping the diamond drill bit cool: Electroplated diamond coating will wear off if the tool gets too hot.  Never let your drill bit run dry.  Here is how you could use water to keep the tool cool:
    a- You can build a mini water dam around the hole with plumbers putty.
    b- You can choose to spray water on the drill bit.
    c- Or you can use running water to cool the drill bit.
  2. Keeping the drill bit in position

If you are using a drill press positioning is not much of a challenge. But if you are using a hand drill, it could be more difficult.

With hand drills, we recommend using a piece of thick cardboard or plastic with a hole as your guide.

Please refer to our post about this topic.

Why Not Any Pilot Drill Bits?

Based on our experience, most of the diamond-coated drill bits – hole saws are manufactured without a pilot drill bit. People expect pilot drill bits based on their experience with soft materials such as wood, plastic, metal.
Pilot drill bits are not good for brittle materials. They will crack glass – tile – granite, etc. We specifically do not have the pilots because
a) pilots get dull before the hole saw b) pilots have a tendency to crack brittle materials like glass.

Instead of a pilot drill bit, we recommend guiding the hole saw with a piece of scrap wood guide. Please check our instructions on drilax page.
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Do do you sell drill bit hole saw guide that will accommodate a 4″ hole saw?

It is possible to use our guide with 4 inch hole saws, only if you remove one of the plates.

The suction cup side will have a triangular wedge like constraint on the hole saw. This is enough to hold the hole saw in place.

But overall, this is not the ideal use of a guide. Can be a plan B in case you can’t find a guide.

Or you can make a 4 inch hole in a piece of plywood, and use it as a guide. Using some painters tape, you can fix your plywood guide to the surface.

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What is the recommended Drill Speed Diamond Hole Saw?

Drill Speed Diamond Hole Saw

How to adjust the speed of the drill for diamond hole saw.

The best use of diamond hole saws requires the correct speed and cutting conditions. The drill speed diamond hole saw depends on the dimension of the diamond hole, the material, and the depth of cut.

The ultimate goal is to drill the hole without overheating the tool. Please use the table below as a reference.


Diamond Hole Saw Diameter
Type Of Material 3/8” ½” 1” 1-1/2” 2” 2-1/2” 3”
Granite 500 500 400 300 200 150 100
Porcelain/Ceramic Tiles 500 600 500 400 300 200 150
Glass 700 700 600 500 400 300 200
Marble 600 600 500 400 300 200 100
For concrete or masonry please prefer our HEAVY DUTY products.
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How to drill bottom of flower pots?

Most of the decorative flower pots do not have the bottom drainage holes. They look nice but you do need the bottom hole.

For drilling the bottom drainage holes, you will need diamond coated hole saws.

Drilling Bottom of Flower Pots – Making Initial Mark

Drilling Bottom of Flower Pots – Making Initial Mark (images provided by a Drilax Customer on platform in the form of a review)

Best diamond coated hole saw drill bits come with no center pilot drills. Pilot drill bits are for softer materials such as wood or plastic.

To make your initial mark, you can either start at an angle or you can make your own guide with a piece of scrap wood.

After you make your initial mark, you can even out the drill bit and go full vertical.

Cooling the drill bit is very important. How diamond hole saws will lose the diamond particule. You can use water or ice.

Cooling Diamond Hole Saws with Ice

Here is what the finished hole at the bottom of a flower pot looks like:

With effective cooling, we are very proud to tell you that Drilax diamond coated hole saws will serve you many many times with great performance. Here is a picture from a previous shopper:

We thank T. Robertson and AnneisAwesome for their great images. These images were posted publicly on

All these beautiful flower pots have been drilled with Drilax tools.

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Making Decorative Lamps Using Bottles or Jars

Convert your old bottles or jars into unique decorative lamps.

Cut holes in the back of bottles to insert lights. You will need diamond coated special tools for drilling the holes.

Practice on a piece of glass and move on to your projects.

Starting at an angle helps to get the diamond drill bit make the mark.

Once you make the mark, even out the drill. Take a glass of water with you and keep the tool cool.

Here are some lamps that were made by Drilax customers.

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Attaching the Drilax Flexible Shaft to a Rotary Tool

The product is available for purchase in our store.


1- First, if your rotary tool has a threaded collar on the motor end, you will need to remove it by turning CCW (counter-clockwise). You will need the collar when you attach a tool directly to the rotary tool. You will not need it with the flex shaft.


2- Hold the flexible shaft by the silver color fitting end (you will be able to see the inner shaft core). And pull the inner core about 2 inches. If you need a pair of pliers to hold it, that’s normal.

It is a very good idea to grease (lube) the inner core.


We recommend using white lithium grease to lubricate the inner core of the Dremel Extension. 




3-Now, the idea is you are attaching the core of the flex shaft into the rotary tool collet just like you would attach any kind of tool with a 1/8″ shaft. The flex shaft is there to transfer the rotation, that’s it. It is just like an extension. Push the core of the flex shaft into the rotary tool collet and tighten the collet. You can use the collet lock button to prevent it from turning while you are tightening the nut.

4- You can now screw the silver color fitting end of the flex shaft onto the  rotary tool housing. This is where you removed the collar. We are now done attaching the flex shaft to the rotary tool. From now on, the next steps are about attaching the bit or burr to the flex shaft.


5- The other end (BLACK COLOR) of the flex shaft is where you will insert the desired attachment tool such as a diamond disc or a burr. You will be using the silver chrome L shaped piece for this stage. There is a hole on the side of the black side of the flex shaft. And there is another hole under the black side. When you align these two holes by turning the silver tip on the black end, insert the L shaped metal. This step may sound confusing but it’s simple. The inner metal part on the black end of the shaft will want to turn as you try to attach the tool. The L shaped metal is there to help you hold it while you try to twist the tip.



6- You can now attach the bit. And tighten the nut at the tip of the black end of the flex shaft. 

Tool attached to flex shaft
The tool attached to flex shaft



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Drilax Diamond Drill Bit Hole Saw Guide Jig Fixture


Drilax Diamond Drill Bit Hole Saw Guide Jig

Hole Saw Guide Jig Fixture Vacuum Suction Base with Water Coolant Hole for Tiles, Glass, Fish Tanks, Marble, Granite, Ceramic, Porcelain Guides Holes up to 3 1/4 Inches

Quick Tip 1: Using diamond hole saws, it does not matter which way you run your drill. If you are concerned with the nuts unscrewing, we suggest you run drill in reverse (counter-clockwise). This will prevent hole saw guide bearing nuts from unscrewing.

Quick Tip 2: You do not need the guide for the entire duration of the drilling. Once you have made a mark on the material, the hole saw will keep in position.

Quick Tip 3: Do not forget to use water. It is OK to stop drilling for a cleanup and cooling.



Diamond Hole Saw Guide Jig Fixture

  • Durable Plastic Diamond Hole Saw Guide Jig Fixture with Suction Base – Integrated Water Hole
  • Adjustable Plate to Guide All Sizes of Hole Saws up to 3 1/4″ Drill Diameters – Flip the plate
  • 1 Side of the Plate for Drills up to 3 inches, and Flip the Plate for Larger Sizes up to 3 1/4″
  • Use the Guide to Start the Hole – Remove the Guide for the Remainder of the Hole
  • Secure The Guide with Suction Base – Feed Water through the Integrated Hole


Drilax Drill Guide - Large HoleSaws

High-Quality Plastic Diamond Hole Saw Drill Guide with Suction Cup Base

Product Base Dimension: 6″ x 8″

Maximum Hole Saw Dimension: 3 1/4″

Plate Face A: Holes up to 3 inches

Plate Face B: Holes up to 3 1/4 inches

Flip the plate to switch from Side A to Side B

For smaller sizes, you can remove the ball bearings.

Diamond Hole Saw Guide  – Perfect Hole Starter for Ceramic, Glass, Granite, Porcelain or any smooth surface where the suction cup base can hold on to – Including Walls

How to use the hole saw jig:

1. Adjust the sliding plate for the size of the hole saw – drill bit you want to use. One side of the plate is for sizes up to 3 inches and flip the plate for larger sizes up to 3 1/4″

2. Fix the guide using the suction base exactly where you want to drill the hole. Check the drill guide location and slider position before you start drilling. Measure – check twice and drill once.

3. Using water as a coolant, start the hole. You can spray the water or use the integrated hole.

4. Use the guide until the drill bit – hole saw makes an initial mark deep enough to keep the bit in position. You can remove the guide and continue drilling in the same spot.

5. While drilling, keep using water to cool down the diamond drill bit – hole saw. Spray bottles, running water, or a small water pool around the hole can be used to cool the tool.

Drilax Diamond Hole Saw Jig Drill Guide

The suction cup of this hole saw jig is strong enough to hold the guide and the drill bit on the wall – vertical orientation:

Here is a video made by one of our previous customers:

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Jewelry Making

Drilling Sea Shells – Sea Glass – Rocks – for Jewelry Making

There are great sets for jewelry making. Click here for reviews and prices.


Please a take look at this great blog for DIY information and discussions.

How To Drill Sea Glass

What You Will Need:

Initial Set Up

  • Mark your piece when you want to drill
  • Fill up your plastic shallow dish with water (about 1 inches deep)
  • Select your drill bit, attach it with your chuck or collet, get ready to drill


Always be extra careful water near an electric drill. Make sure your drill and working area and of course hands stays dry. Do NOT touch electrical appliances with wet hands.

How to Drill Sea Glass

1- Keep the sea glass in the water with your fingers or a type of wise / clamp.

2- Angle the diamond drill bit at about 45 degrees (90 degrees is perpendicular, so half way in the middle).

3- Start your drill at your slowest speed, do not apply too much pressure.

Please be patient.

Do not speed up your drill or apply extra pressure.

You will eventually make a hole, 1 minute sooner or later. Do not lose your patience. You may end up breaking the piece, your drill bit or ruin the tip of the bit.

4- As soon as you make your initial mark, slowly move the drill to perpendicular (vertical) position.

5- Keep it slow and with light pressure.

6- Every 10-15 seconds, move the drill bit up and let water in the hole you make.

7- To give you an idea, you can drill a regular sea glass within 60 seconds.


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Drilling Glass Blocks

Drilling in glass block or bottles is not different than drilling in traditional glass.  If you employ the acceptable speed, use low drill pressure and lots of water for lubrication, you will not have any issues.  Glass breakage with inorganic compound bits is fairly common, however with the right diamond drill bit, it’s very rare.  There are a couple of vital facts and tips which are useful for drilling glass blocks.


There are various differing types and designs of glass block created by many alternative makers.  Most have some style of style or pattern, however, for drilling functions, there are 2 main characteristics.  Glass blocks will vary considerably on the thickness of the glass wall and a few glass block is tempered.  This info is never disclosed on the block itself, however ought to be thought-about once shopping for glass block for crafting functions.

If the glass block is 3/8″ thick, it’ll take thrice as long to drill compared to a 1/8″ thick block.

Tempered glass ought to be avoided.

Making a mini dam around the hole is the most effective cooling method for drilling in glass blocks.

Glass block contains a vacuum within. a number of the water and glass dirt can forever be sucked within once the opening breaks through.  However, it’s simple to rinse out {the within|the within} of the block with water as long because the dirty water inside isn’t allowed to dry out.  The plug from the opening can generally be force into the block – it’ll typically drop out simply once the within is rinsed.  However, if an excessive amount of pressure was placed on the drill because the hole breaks through, it will cause the plug to possess a aptitude from the break on the rear of the opening.  Normally, you’ll be able to take away the plug with a combine of needle nose pliers, however the simplest answer is to scale back the drill pressure once nearing the rear of the glass to avoid break because the drill breaks through.


There is a great set of 5 diamond drill bits with the best selection of sizes on Amazon.  Previous customers were able to 10 to 30 holes in glass with 1 single bit.


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The Speed of the Drill

For smaller sized holes, such as 1/2″ or smaller, the maximum suggested speed is 600 RPM.

Larger holes will need slower drilling speeds, for example:

400 RPM for 1 inch Holes
200 RPM for 2 inch Holes
125 RPM for 3 inch Holes

The idea is, as the speed increases, there is more and more friction on the rim of the drill bits and the coolant can not stay on the surface.

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Keeping the drill bit on target

Most of the diamond-coated drill bits – hole saws are manufactured without a pilot drill bit.  People who are used the pilot drill bits from wood – plastic hole saws, may think of this as a missing component but it is actually done on purpose. Because pilot drill bits will crack glass – tile – granite, etc.


We specifically do not have the pilots because a) pilots get dull before the hole saw b) pilots have a tendency to crack some materials like glass

To help to start the hole, we have a guide. Click to read reviews on Amazon.

You have to have a way to keep the drill bit on target. Here are some methods:

a- You can make your own guide out of plywood – plastic or even cardboard. All you need is to keep the drill bit in place until it makes the initial marks.

Using Scrap Wood To Start Hole with Diamond Holesaw in Tile - Kitchen Renovation
Using Scrap Wood To Start Hole with Diamond Holesaw in Tile – Kitchen Renovation

Using 2 Pieces of Scrap Wood with Tape To Start Hole with Diamond Holesaw in Granite Countertop - Kitchen Renovation
Using 2 Pieces of Scrap Wood with Tape To Start Hole with Diamond Holesaw in Granite Countertop – Kitchen Renovation

Using Cardboard To Start Hole with Diamond Holesaw in Wall Tile - Bathroom Renovation
Using Cardboard To Start Hole with Diamond Holesaw in Wall Tile – Bathroom Renovation


b- You can start drilling at an angle, with the edge of the drill bit making a C slot and then getting the drill bit up to vertical.

 If you have one of our sets that come with the PU case and insert, the inserts can also serve as a guide to start the hole.

High-Quality Poly Insert Can Be Used as a Guide

Please consider using our drill guide on Amazon

Here is what one of customers said about our guide:

I was anxious about drilling into my granite countertop. The Drilax guide was easy to size to my 1 1/2" diamond hole saw. I located the hole position & locked the guide into place. Once I began drilling, I felt totally at ease that the hole saw would not skip about. Huge success, remarkable value. My confidence in accurately cutting through granite, marble or tile is very high using this guide.”

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How to Use These Diamond Coated Hole Saws – Drill Bits?

Most Important Rule of Thumb: Never let your drill bit run dry.
This may sound trivial but heat is the most important factor for the life and performance of these tools.
The use of cool water is a simple and effective way to keep the tool from burning up.

Over the years we have seen:
a- People building a mini dam around the hole with plumbers putty or similar materials.

b- Some prefer spraying water on the drill.

c- Some use running water to cool the drill bit.
d- There are people using crushed ice with cold water.