Build a magnetic knife holder

To make it easy for you, we have tested a large number of magnets and noted how much distance there can be between the knife and the magnet without the knife slipping down. You'll find this chart a little further down. If you find a magnet in the shop that is not in the chart, we will be happy to do a strength test on it. Just write to info@brisingi.com

To create the chart below, we tested a chef's knife weighing 210 grams. We started with a distance between knife and magnet of 2 mm and gradually increased the distance by 1 mm. For each test, the result was noted in the chart you see below.

In the table below you can see three different symbols in the ‘configuration’ column. The symbols indicate how the magnets are positioned inside the blade holder. The magnets can of course be placed as you like, but these three configurations are often used.

◯
The symbol indicates that the knife is tested by holding the knife with a single disc magnet.

▬
The symbol indicates that the test was performed by holding the blade with a single block magnet placed horizontally.

⚌
The symbol indicates that the test was performed by holding the blade with two block magnets, both positioned horizontally. One magnet above the other magnet.

⬤
The green circle indicates that at this distance the knife is stuck without sliding down. At the same time, the knife is not so tight that it is difficult to release from the knife holder. This is the ‘sweet spot’.

⬤
The yellow circle indicates that at this distance, we estimate that the knife is too difficult to release from the knife holder. If you want the knife to be really tight, you can go for the yellow circles, but usually it's the green circles that we have tested work best.

⁒
The ⁒ symbol indicates that the knife cannot be held by the magnet at this distance. Either reduce the distance or use a magnet with a higher strength.

If you're drilling holes in the wood with a drill, disc magnets are the obvious choice as they fit right into the hole. But consider drilling the holes very close together to avoid the blade ‘wobbling’ to the nearest magnet. If you want to use square magnets (block magnets) instead, you can use a cutter to make a groove in the wood. The advantage of block magnets is that they can be joined together into one long magnet, thus avoiding the aforementioned ‘wobbling’ effect.

If you're drilling holes in the wood with a drill, disc magnets are the obvious choice as they fit right into the hole. But consider drilling the holes very close together to avoid the blade ‘wobbling’ to the nearest magnet. If you want to use square magnets (block magnets) instead, you can use a cutter to make a groove in the wood. The advantage of block magnets is that they can be joined together to form one long magnet, thus avoiding the aforementioned ‘swallowing’ effect.

For the sake of clarity, we can make this list:

• Disc magnets
  • Disc magnets are easy to install as you only need to drill a hole for each magnet.
  • It's easy to organise the knives as there will typically be one knife on each magnet.
  • If the handle (the heavy end) is facing upwards on the knife holder, you may find that the knife turns sideways or all the way round. You can avoid this by using a stronger/larger magnet or adding a smaller support magnet to prevent the knife from turning.
• Block magnets
  • You can make a long continuous magnetic bar so that the knife holder doesn't swing to the nearest magnet, as is the case with disc magnets.
  • If you don't have a cutter, it can be difficult to make the groove for the magnets to lie in.

Neodymium magnets are very powerful with direct contact between magnet and metal. When you make a magnetic knife holder, there is a gap between the knife and the magnet. This distance greatly reduces the strength of the magnet. In addition, the knife tends to slide off the knife holder because both the knife and the knife holder are smooth. To avoid this, you need a strong magnet that can hold the knife in place.

If you stick to the overview table, you're off to a good start. If you're still in doubt, consider buying a magnet that's a little too powerful. This is because you can simply increase the distance to the knife by 1 mm at a time until you reach the point where the knife is firmly attached but can also be removed from the knife holder without using too much force. If the magnet is too weak from the start, you lose the ability to increase the distance as the magnet will not have the strength to do so.

If you want the handle of the knife, i.e. the heavy end, to face upwards on your knife holder, you may risk the knife turning round because the heavy end wants to point downwards. There are a few things you can do to avoid this:

• Use magnets that are strong enough to hold the knife firmly enough to prevent it from spinning.
• If you use disc magnets, you can use a strong magnet to hold the knife up. On top of that, place a smaller disc magnet, which only serves to prevent the knife from spinning.
• Make two horizontal rows (===) of block magnets. The two rows ensure that the knife cannot turn.
• Instead of placing the block magnets in a horizontal (----) row, place them vertically with a distance between each magnet ( | | | ).

Often the magnets are glued in place. Others clamp the magnets or enclose them in the wood by gluing wood on top of the magnets or simply filling with epoxy.

It's not so important which glue you use. You can use superglue, wood glue, epoxy or whatever you like best. Just avoid exposing the magnets to temperatures higher than 80 degrees. So don't use glue guns. We offer a superglue that we can guarantee will keep the magnets in place. You can find it here: UHU Max Repair

If you know that the distance between magnet and blade will not be less than 4-5 mm, you can use an ordinary wood drill. If the distance between the magnet and the blade is less than 4 mm, you need to be very careful. Most wood drills have a guide tip that sticks out slightly. You risk it drilling all the way through the wood, which you don't want. Instead, consider using a ‘forstner bit’. It has no point and you can drill deeper without breaking through the wood.

If you have made your own magnetic knife rail or other project with our magnets, please send us some pictures and some text about how you did it. If we can use the material on our blog, website and social media, you will receive a 15% discount on your next order. Write to info@brisingi.com with your material.

Two of these magnets were used Block magnet 40x20x5 mm

Made by Dan L.

Two of these magnets were used Block magnet 40x20x5 mm

Made by Rupert S.

Two of thse magnets were used Disc magnet 20x10 mm

Made by Jeppe M.