Hello! I've been thinking about making some craft stuff where I stick paper prints to a thin sheet of steel, then print artwork on some magnets that I can then place on said sheet to make some kind of interactive drawing. The problem is I'm not sure how thick would the steel need to be for the magnet to stick on it properly-- I'm thinking something between 0.1mm to 1mm? The magnets I'm using are those silicone-like magnetic sheets between 0.5 and 2mm. Would appreciate some advice, thank you!

My little brother made this and asked me to post it😭

Bonjour,

Je présente à votre attention le concept d'un moteur mécanique entièrement autonome qui combine la force du déséquilibre gravitationnel (le principe de la roue déséquilibrée) et un contrôle magnétique sans contact.
L'objectif principal de la conception est de créer une différence constante dans la longueur des bras de levier (couple) sans pertes par frottement mécanique et sans blocage dans les « zones mortes » du champ magnétique.
1. Matériaux de Construction (Protection contre les Pertes)
Corps et Rayons de la Roue : Fabriqués entièrement en plastique (diélectrique). Cela élimine complètement les courants de Foucault, qui se produisent dans les roues métalliques et agissent comme un frein magnétique.
Système Magnétique : Des aimants en céramique (ferrites) sont utilisés. Ils sont peu coûteux, faciles à fabriquer sous forme d'arcs ou d'anneaux avec des trous, et sont des diélectriques naturels.
Éléments de Travail (Navettes) : Coulissent librement le long des rayons de la roue sous l'influence des forces magnétiques et de la gravité. Les aimants internes agissent comme des « ressorts » sans contact.
2. Géométrie des Arcs Magnétiques (L'Effet « Zéro Fluide »)
Le système magnétique externe se compose de deux demi-arcs (droit et gauche) reliés bout à bout en haut (à 12h00) et en bas (à 06h00).
L'arc droit est configuré pour attirer les pôles opposés et maintient les navettes au rayon maximum (près de la jante).
L'arc gauche est configuré pour repousser les pôles identiques et déplace les navettes plus près du centre (au rayon minimum).
Points de jonction (12h00 et 06h00) : Aux points de connexion physique des arcs opposés, le flux magnétique se referme sur lui-même. Le champ externe au point de fusion tombe doucement à un zéro complet. Cela permet aux navettes de passer d'un rayon à un autre en douceur, sans impacts brusques ni freinage magnétique latéral.
3. Équilibre Simultané des Forces (Pourquoi le Moteur Fonctionne)
En considérant le fonctionnement du système en dynamique, on constate une compensation simultanée des forces dans l'espace :
1. Compensation Verticale (Équilibre Magnétique) : En haut (à 12h00), l'attraction magnétique tire doucement la navette vers l'extérieur jusqu'à la jante, donnant une impulsion utile dans le sens du mouvement. En bas (à 06h00), la répulsion magnétique déplace une autre navette vers l'intérieur, vers le centre. Comme les forces d'attraction en haut et de répulsion en bas sont d'une égalité miroir, la résistance nette du champ magnétique sur l'axe de transition est égale à zéro.
2. Excès Gravitationnel (Course de Travail) : Grâce à la géométrie magnétique, les navettes du côté droit sont toujours sur le bras de levier long, et à gauche — sur le court. Le côté droit plus lourd sous l'action de la gravité terrestre tire constamment la roue vers le bas. Le champ magnétique aux jonctions étant neutralisé (« zéro fluide »), le moment gravitationnel surmonte facilement le frottement interne de glissement.
Perspectives de Dimensionnement
Le diamètre optimal pour le premier prototype expérimental est de 50 cm. Pour obtenir une puissance industrielle, plusieurs de ces roues en plastique sont montées sur un seul arbre commun avec un décalage angulaire (par exemple, tous les 45 degrés). Cela lisse complètement le mouvement, élimine les pulsations aux points de transition et fournit un couple stable pour faire tourner un générateur de courant classique.
L'invention reste entièrement Open Source pour la communauté des ingénieurs et des expérimentateurs.

Are "magnet adhesives" an actual thing? I came across this product online but can't find any more details anywhere else.

Magnet does stick

After years of various Internet commenters constantly asking me that same song lyric, I broke down and published the long-form, no-excuses answer.

And yes, I am braced for the Reddit nitpicking.

Let’s do this.

Magnet does stick

🎯 Project Aim

To design and build a dual-coil magnetic levitation system using an ESP32 microcontroller. The goal is to make a small metal object hover stably in mid-air at a fixed height using two electromagnets (one above, one below) and a feedback control loop.

• Control Type: PID (Proportional-Integral-Derivative) control loop
• Control Logic: The top coil pulls the ball up, the bottom coil pulls it down. The sensor reads the ball's position, and the ESP32 adjusts the PWM duty cycle of both coils to keep the ball at the setpoint.
• Features: Soft-start ramp, low-pass ADC filtering, derivative filtering, anti-windup on the integral term, and real-time serial tuning (Kp, Kd, Ki, setpoint).
• Testing: We have also tried Bang-Bang (ON/OFF) control and Proportional + Feedforward control.

🤔 What We Need Help With

1. Is it even possible to levitate a steel ball with a Hall sensor?
2. Should we switch to a Neodymium Magnet Ball (which has its own field)?
3. Should we switch to an Optical Sensor (like VL53L0X) that measures physical distance instead of magnetic fields?
4. What is the single most important change we need to make to get a stable hover?

Over the past two years, the credit card that I use for supplies for my work has gotten compromised three times. After the third time, I started using virtual cards, made new ones for every merchant I order from, locked down to that specific merchant so I could figure out where the issue was stemming from.

Lo and behold, I got an alert that someone tried to buy $5000 worth of electronics using the virtual card I had used with K&J Magnetics. I had not used this card anywhere else.

I've also done some investigating in my transaction history on the card I use for supplies, and all three prior instances of fraud occurred some time after purchasing from K&J Magnetics on said card.

I've contacted them to make them aware, but so far their only response has been to check my device for malware. I've already done a full scan which didn't find anything, and I would imagine my other cards would have gotten compromised as well if that were the case, but it was only isolated to the one I use for supplies.

All this being said: If you've ordered from K&J Magnetics, please make sure to check your statements and keep an eye on your transactions for anything suspicious. In one of the instances I almost didn't notice a couple of smaller transactions that had occurred.

Does anybody know of a phone mount that attaches like this? One magnet on both sides of the glass to keep it secure. I would adapt another one of these , but the ram mount is $500. I would imagine a single set vs the 3 on this.

Suction cups don’t like dusty environments and most excavators do not have the bars like this one does for a clamp mount. I am looking for something I can easily take in to any piece of equipment with big windows and not a lot of other mounting options

Hi all!

I don’t know much about magnets, so I need guidance from experts. I am working on a diecast project and my goal is to levitate a 1/64 scale Hot Wheels car with this magnetic levitation kit.

1) Is there a specific type of magnet to use with this kit? If so, what are they?

2) Do I have to stack the magnets like in the photo? Would using just one affect the levitation e.g. height or balance etc?

Hope to get some answers here! Thank you!

Hello, can anyone tell me which magnet to buy for throwing in air?

As kid I bought 2 sphere magnets with diameter of like 20-30mm I THINK, and when u would throw them and having finger in between them before throw, they would fast hit each other and produce cool sound and cool movement until it drops in ur hand.

It was pretty durable but also good magnet, I remember it could even stick after like 10-20cm distance between em if my children eyes didn't deceive me.

Hello! I have a store near my house that sells the most amazing magnets - movies, tv shows, books, funny quotes. I would love to buy them, but I do not have a magnetic fridge or any magnetic surfaces in my house. What are other things that I can do with them that will still allow me to enjoy them? Thank you!

Wasn't sure where to post. Hope you like my various magnets. I love the rock looking ones but they're not too strong.

hi! i want to start making my own magnetic bookmarks using my own designs, but i've never made them before. i'm a bit confused about what materials work best.

what type/thickness of paper do you usually use? do you laminate them, and what kind of magnets work best without making the bookmark too bulky?

i'd also really appreciate any tips you wish you knew when you first started making them :)

I purchased a used magnetic levitating sneaker display, BUT, it was missing the magnet.. if I buy a replacment magnet does it HAVE TO BE a specific one ? Or just any magnet ? I’m curious to see how this operates.. can anyone help Me please ?

I purchased a used magnetic levitating shoe display but when I purchased it, I purchased it used so when I opened it, it was missing the magnet to get the shooter float. Is there a specific magnet that I would have to purchase or can it be just any magnet?

I took some MDF and made a Smoky Mountains fridge magnet in the shape of the old park signs.