The diamond core bit set from Fairmo made a very good impression in our test. Drilling holes is very easy with the four diamond core bits with diameters between 25 mm and 68 mm using an angle grinder. Individual shapes can also be milled out with the included finger grinder. The tools can also be used in a cordless screwdriver thanks to the adapter supplied. However, this requires a little more skill than with an angle grinder.
Advantages
✅ Precise drilling
✅ Clean edges
✅ Individual shapes with the finger grinder
✅ Suitable for angle grinders with M14 thread
✅ Adapter for cordless screwdriver
Disadvantages
❌ Use in cordless screwdriver requires skill
❌ No telephone number given
The test
General information
We have looked at and tested the product in detail in a practical test. In the following, we take a closer look at the features and impressions. The product is subjected to our test procedure from the packaging, materials and quality to the range of functions and handling.
To give you a quick overview, we work with a points system. The maximum possible number of points per area is 100 points. The final overall score is calculated from the average of all tested features, taking into account the respective weightings. For a detailed insight into our comprehensive evaluation process, which forms the basis of all our product ratings, please click here.
The first impression
Packaging and labeling
ℹ️ Here we take a closer look at packaging. Sustainability is becoming an increasingly important factor. In addition, adequate protection of the product must of course also be ensured.
| Criterion | Remark | Score achieved* |
|---|---|---|
| Product protection | Carton is sturdy, product sufficiently protected | 100 points |
| Sustainability Packaging | Apart from the foam board, there is no unnecessary packaging waste | 90 points |
| Packaging convenience | Can also be opened easily without tools | 100 points |
| Total | 97 points |
*The maximum score is 100 points
The diamond core bit set from Fairmo arrived in an almost perfectly fitting shipping box. The box contained the diamond core bit set in its product packaging. Due to the appropriate size of the shipping box, the product packaging could only slide around a few centimeters inside. The diamond tile drill bit set and the associated product packaging were undamaged and in perfect condition.
The product packaging is printed in dark green with orange accents and matches the product well visually. As it was not glued, it is easy to open without tools.
The product packaging contains the case with the tools. At the top of the box is a thin foam board. This could have been dispensed with for reasons of sustainability. The two boxes and the case provide excellent protection for the tools during transportation.
After unpacking
Package contents and instructions
ℹ️ Most people’s first impression after unpacking is immediately memorable. Are the contents of the package complete and does the manufacturer make it as easy as possible for me to use the product straight away?
| Criterion | Remark | Score achieved* |
|---|---|---|
| Package contents & scope | Comprehensive set comprising four diamond core bits, a finger grinder, an adapter and a case | 100 points |
| Instructions for use | Written on the product packaging in German and easy to understand | 100 points |
| Contact information | On case and product packaging, unfortunately without telephone number | 90 points |
| Total | 97 points |
*The maximum score is 100 points
The set consists of a total of seven parts: Four diamond core bits with diameters of 25 mm, 35 mm, 50 mm and 68 mm, an adapter for cordless screwdrivers, a finger cutter and the case. The set therefore offers a comprehensive selection of tools for working on tiles and granite slabs.
The instructions for use can be found on the back of the product packaging. Here you will find instructions for use with tips and warnings. The instructions for use are written entirely in German and are easy to understand and use pictures to visualize the tips. This means that the product can also be used by DIY enthusiasts who have never worked with this type of drill before.
The contact information can also be found on the product packaging. It can be found on the underside and includes the company name, address and an e-mail address. Unfortunately, there is no telephone number. The warnings and contact information are also printed on the back of the case.
The first time in your hand
Product processing and appearance
ℹ️ Before we start the practical test, we take a close look at the product processing. How high quality are the materials used? Is the look and feel satisfactory?
| Criterion | Remark | Score achieved* |
|---|---|---|
| Visual appearance | All tools are completely and evenly painted in green, the adapter is black | 100 points |
| Processing | All parts are well made | 100 points |
| Stability | The tools are made of solid metal with high wall thicknesses | 100 points |
| Sustainability of the product | Very sturdy tools suggest high durability, unnecessary plastic tray in the case | 90 points |
| Suitcase | Practical for storage and transportation, but the recesses are too small to remove the tools | 90 points |
| Total | 96 points |
*The maximum score is 100 points
The case consists of two plastic halves, which can be quickly closed with a clamping mechanism. It has a practical carrying handle on the top. The lower half is filled with black foam, which contains precisely fitting recesses for all other parts of the set. The recesses are very narrow, which means that the tools are held securely in place despite their relatively high weight. The two large drill bits protrude from the foam and are therefore easy to remove. The other, smaller tools and the adapter are fully recessed in the cut-outs. There is therefore a small bulge in the recess to reach in with your finger. Unfortunately, the recess is too small to grip the stuck tools with your finger. However, the tools can still be released with a little finger force. There is an additional transparent plastic tray in the upper half to protect the tools from falling out. However, as these are firmly anchored in the foam, this would not have been necessary.
The diamond core bits themselves are made of solid metal and are therefore very sturdy. All four sizes have the same flange with an M14 internal thread on the underside. The flange has two flat sides that can be used with pliers to remove tools that are screwed in tightly from the angle grinder or adapter. The actual drill bit is located above the flange. This is hollow on the inside, has two openings for discharging drilling material and a very rough, sparkling silver diamond tip. All drill bits are 60 mm high. The actual drill bit accounts for 40 mm of this. The diamond tip extends over 10 mm.
The finger grinder also has a flange with an M14 internal thread and flattened sides. Compared to the drill bits, however, this is thinner. In contrast to the drill bits, the working side is not hollow and is completely covered with the rough diamond coating. The overall height of the finger grinder is 65 mm, the working area extends over 40 mm and has a diameter of 20 mm.
The adapter for the cordless screw has an M14 external thread on one side to which the five tools can be attached. Opposite this is a hexagonal insert, which can be easily clamped into standard cordless screwdriver holders. In the middle of the adapter there is a wider area which serves as a stop for the tools and, like the tool flanges, has two flattened sides.
This is what our practical test showed
Does the manufacturer keep its advertising promises?
ℹ️ Our practical test is the most relevant and therefore the most important. Here, the product has to undergo a wide range of criteria and tests. We check the functions and product promises of the test article.
| Criterion | Remark | Score achieved* |
|---|---|---|
| Mounting the tools | Quick screw-in, precise thread fit | 100 points |
| Drilling with the drill bits | Fast and clean drilling with the angle grinder | 100 points |
| Working with the finger sander | Precise processing of edges possible | 100 points |
| Use with adapter in cordless screwdriver | Adapter works, but drilling requires more skill than with an angle grinder | 80 points |
| Total | 95 points |
*The maximum score is 100 points
We start the practical test by using the tools in the angle grinder. The diamond core bits can be easily screwed on using the thread. The angle grinder is ready for use after just a few seconds.
A standard tile, as used in bathrooms, serves as the test object. To drill a hole, the tool is held at a 45° angle to the surface as described in the instructions. Due to the reduced contact surface, a crescent-shaped indentation is quickly ground into the tile. The angle grinder can be guided precisely and the tool does not jump away. The hole is created exactly where it is intended. Once an initial indentation has been made, the tool is slowly tilted and drilled further until it is perpendicular to the surface. The hole can now be completed. The drilled holes have almost smooth edges and the edges of the holes do not chip. This applies to both large and small holes.
You should wait a short time after drilling, as the tool becomes very hot during use. Once it has cooled down, it can be changed just as easily as it was fitted. In our test, the drill core remains in the tool as a disk after drilling. It can be easily removed from the tool using pliers or a screwdriver, but with a little patience it can also be removed with your fingers. The recesses on the edges of the diamond core bits prove to be very helpful here.
In the next step, we test the finger grinder. It is mounted on the angle grinder in exactly the same way as the diamond core bits. In contrast to the diamond core bits, the working surface here is not at the tip of the tool, but at the side. In our test, the targeted widening of a drill hole and the precise shaping of tile edges was flawless.
In the last part of our test, we use the diamond core bits in the cordless screwdriver. To do this, the tools are first screwed onto the adapter, which can then be clamped into the cordless screwdriver. This is also done quickly. However, drilling with the cordless screwdriver is not quite as precise as with the angle grinder. Due to the significantly lower tool speed despite the second gear, the tool tends to jump away when it is started. The cordless screwdriver must be guided with two hands and a firm grip in order to drill the hole exactly in the intended position. However, once you have made a start and successfully drilled the first hole, the rest of the drilling is just as easy as with the angle grinder. This means that the diamond core bits can also be used with a cordless screwdriver. However, if you have the choice, you should go for the angle grinder.
Overall, the diamond core bit set from Fairmo performs very well in the practical test. The diamond core bits can be used to drill holes precisely and quickly, and the finger grinder can be used for finishing touches. Thanks to the adapter, the tools can also be used in a cordless screwdriver, but the use of an angle grinder is recommended.
Price/performance ratio
and ratings from consumers
ℹ️ Finally, we look at how the product compares to the competition. Can it keep up with the competition in terms of price and quality? Would we generally recommend buying it? We also examine consumer ratings and check whether the critical and positive reviews are actually justified.
| Criterion | Remark | Score achieved* |
|---|---|---|
| Price / performance ratio | Very good quality in the mid-price range | 70 points |
| Rating cut | 4.9 out of 5.0 on Amazon | 95 points |
| Total | 83 points |
*The maximum score is 100 points
On the Amazon platform, consumers have given the product an average rating of 4.9 stars. One common complaint is that using the cordless screwdriver requires some skill. Many customers like the good functioning of the angle grinder and the finger sander. We were able to confirm these points in our practical test.
Prices of up to €125 are charged on the Internet for equivalent products. Very inexpensive products are available from as little as €55. The diamond core bit set from Fairmo is currently priced at € 97.90, which puts it in the middle price segment. The price ratio is reasonable for the quality and scope of services you get.
Overall result
| Weighting | Score achieved* | |
|---|---|---|
| 1. packaging & labeling | 10% | 97 points |
| 2. package contents & instructions | 10% | 97 points |
| 3. product processing & appearance | 20% | 96 points |
| 4. in the practical test | 40% | 95 points |
| 5. price/performance & consumer ratings | 20% | 83 points |
| Total | 93 points |
The Fairmo diamond core bit set therefore receives an overall score of 1.4 from us and has therefore been successfully certified for our test seal. The test was carried out during the test period 12/22 and is listed in our database under the license number 221109006. You can find more information about our test procedure at www.prüfengel.de/testverfahren.
Test result:
1,4
