Magnet fishing in XL

Two instructions for making your own magnetic fishing rod

Submitted by: M. B.

Online since: 27/08/2009

Table of Contents

Ring magnet as fishing hook

Materials needed for the magnetic fishing rod

For many years I have been looking for old metal objects with a metal detector. The dream of every collector is finding an old cannonball, which is not easy to do. I knew: There are probably countless of those treasures still in the water. But how could I find them? I almost gave up hope - until I ordered a huge ring magnet with an adhesive force of 120 kg.

Required material

Ring magnet R-60-06-30-N
Countersunk screw M6 made of chrome steel
Washer M8 (to increase the bearing surface of the screw head)
Hollow screw M16
Stop nut M8
Ring bolt M8
Shrinking hose (for fastening the nylon rope)
Nylon rope 20-25m

The composition of these parts can be seen on the pictures.

Magnet fishing with DIY magnetic fishing rod

Unbelievable how strong this magnet is! The largest cannonball that I dragged out of the water one night had a diameter of almost 11 cm and was pretty heavy. Meanwhile, I also fished some smaller ones out of the water.

I always have various spectators when I do my "fishing". They are amazed by the huge things I can fish out of the water with this magnet!

Note from the supermagnete team:
Neodymium magnets will start to rust when used outdoors for longer periods of time. The sole exception are rubberised neodymium magnets, which are completely waterproof. Please review the following tips for using magnets outdoors.

Extreme collection magnet with pot magnets

Addition from Thomas Hirsch, Berlin (Germany):

I used the following components to assemble my retrieval magnet:

7 CSN-60
1 aluminium bus 100 cm x 3 cm x 2 mm
7 rust-proof screws M6
7 rust-proof stop nuts M6
1 rust-proof ring nut M6
1 static rope of your choice

You also need a metal saw and a power drill. Saw the aluminium bus into pieces of 6 x 8 cm and 3 x 14 cm. Drill a hole in each center, 1 cm away from both ends. Put it together as shown in the picture. Now you have a big retrieval magnet with a theoretical holding power of 7 x 110 kg, which you can use to "graze" extensive areas. Due to its large scale, stuff really sticks to it. In reality, underwater rust dust and metal splinters quickly stick to the magnets, which reduces their overall adhesive force.

Unfortunately, I didn't have much time to try it out - but here are a few of my "finds": Various steel cables, a ring bolt, a cut bicycle lock type Burg-Wächter F1 from 1997, according to information provided by the company, and a can bottom dated "31 07 1996".

Creator of the photos for this application is Thomas Hirsch, who made them available under the licence Creative Commons CC-BY 2.0.

You can find additional useful information in our FAQ "Questions and answers about magnet fishing". Off-the-shelf fishing magnets that are ready for use right away can be found here:

Go to fishing magnets & accessories

Note regarding the customer project shown:
This magnet project is an application implemented by a customer. The specific parameters for this application – in particular the number, size, arrangement and adhesive force of the magnets, the material, nature and thickness of the mounting surface, dead loads and additional loads, lever actions, as well as environmental and operating conditions – may vary from project to project, and the exact conditions at the customer’s site are unknown to us. Consequently, the presentation of this project does not constitute technical guidance, an agreement on the legal and factual nature, a guarantee or an assurance that a comparable design would be suitable, sufficiently strong or safe under different conditions.

Before any adaptation to another project, it is the sole responsibility of the user to competently assess the specific local and technical conditions. Where necessary, appropriate safety measures must be put in place and professional advice must be sought. Anyone considering a similar application is responsible for verifying the conditions of use specific to their project and for selecting the necessary safety measures.

Our Customer Service will be happy to advise you on selecting suitable magnets, taking your project requirements into account.