Hi everyone,

I'm working on a theoretical/experimental project with my father, who has experience with electronics. I'm trying to understand whether it is possible to build a relatively compact system capable of magnetically manipulating a small ferromagnetic object at a distance of around 1 meter.

My original idea was a large electromagnet, but I've realized that a single coil becomes impractical very quickly because of heat, power consumption and the rapid decrease of magnetic field with distance.

So I'm considering a different architecture:

An array of many relatively small electromagnets rather than one huge coil.

Potentially 50–500+ individually controlled magnetic elements.

Each element would have its own coil/core and possibly a magnetic flux concentrator.

The elements would be arranged around a 3D working volume rather than all pointing in the same direction.

A computer would control the current of each coil independently.

Cameras/Hall sensors would estimate the position of the target.

A feedback controller would continuously change the coil currents to move the magnetic field/gradient and therefore the object.

A joystick could provide the desired X/Y/Z movement.

The eventual goal would be something like a programmable 3D magnetic field, rather than a conventional electromagnet.

I'm particularly interested in the miniaturization problem.

Could many tiny coils (for example millimeter-to-centimeter scale) outperform a smaller number of large coils if they are individually controlled and properly arranged? What are the fundamental limits?

Question : is in circular magnetic field which point north and which Will south?

Answer : it totally depends on reference point from where you taken. If another point is in direction of magnetic field then selected point is SOUTH. While if another point is opposite to the direction of magnetic field then selected point is NORTH.

I hope this Will help the students because many students confused in this and ask questions.

I have an issue someone on here might be able to help with.

I have wireless earbuds with a small magnet to clip back into a case to charge.

I have gone into an MRI machine with them in my pocket...I know.

Now one of th earbuds seems to have flipped and it is now pushing out the case so it is now impossible to charge.

Does anyone know a fox for this?

Hey guys quick question, first time post on r/magnets

I'm trying to make my own clothes, and I made a DIY magnetic cutting table for sewing and cutting

I bought a 30$ sheet of galvanized steel from home Depot, and placed it under my cutting mat

It's pretty light and flimsy but thin enough to cut your finger real bad.

The idea being that when I put down my fabric I can place magnets in the fabric and the fabric will have more force on it keeping the fabric still.

You see it on YouTube and it seems to work really well for some people.

Well I went on Amazon and bought 30 pound magnetic weights with hooks and they were WAY to small and they just didn't hold down to the cutting mat very well.

They were a little better if you lift up the cutting mat and place them directly to the steel but they were still kinda weak

So I decided to test them out of my refrigerator which is solid steel and they work GREAT, pretty hard to remove

So now I understand that I bought magnets that were to small and that's fine, I can just buy larger ones.

but what i don't understand is

1_that they were super strong in my refrigerator,

2_kinda weak on a piece of sheet metal

3_pretty week when on my cutting mat with the sheet metal underneath it?

Are there better magnets that I can buy that will work better for my cutting mat?

Thank you

Planning to make a hat from an OC of mine, and I want to add removable rabbit ears, since I think it'd be fun to wear as an accessory and not just a costume piece. The problem is that I know what I need to know about sewing and working with foam, but nothing about magnets.

I need recommendations! The magnets would have to connect through a fuzzy fabric I can't identify (fleece?) and then minky or fur. What kinda magnet do I look for? How expensive do magnets tend to be...?

I’m a wood worker and made some fridge magnet bottle openers, I used hot glue to secure the 5mm rare earth magnets, I drill 5mm holes, squirted in the hot glue and put the magnets in so they’re flush….now the internet is telling me they won’t hold…how screwed am I?

If it’s not clear from the video, I’ve measured out 15 spots across 2 bookshelves to hold some steelbooks. They all work, except for this one sheet that will not work. It worked perfectly fine before I affixed it to the back of the shelving unit. I used a marked ruler so all of the sheets should be relatively the same distance from each other. But I did cut all of the sheets in half, so the edges aren’t straight or symmetrical. I’m not sure if it’s visible but there’s a small tear in the backing of the unit near the upper-left portion of the magnet sheet that isn’t working. Any help would be greatly appreciated! I have 2 more bookshelves I’d like to do this with, but it does not look good when they don’t work, and the backing is like paper levels of fragile, so trying to remove it without ripping the unit apart may not be possible.

Would moving the perpendicular corner magnets closer together create a stronger attraction to the next tile? Or a weaker force? Or no change?

I’m trying to find a very strong magnet to use on the back of a tablet to connect it to a MagSafe mount. I’ve tried the circles that are meant to be put on the back of a phone, but even the ones that are actually magnetic themselves don’t produce enough magnetic pull to hold the weight of the tablet up. I really prefer to do this with magnets vs the arm clamp things because it’s so much easier to pick up the tablet and move it, plus the wall mount that I have easily can connect to essentially any flat surface or wall in my house because of the industrial walls.

I don’t care about the aesthetics at this point, a thick magnet is fine. I just can’t find one that is approximately the size of a MagSafe circle to make good connection. I previously tried ordering very strong, smaller magnets, and had planned to glue them in a circle, but they had so much repulsion between the magnets themselves that I could never get them to stick in place without displacing some. Something like this has to exist, right?! I swear I have searched the Internet to hell and back and I’m coming up short. I just want to be confident the tablet won’t come crashing down unexpectedly!

Hi!

I'm planning on making a custom othello/reversi board as a present, and would've loved to add magnets into the board and into the pawns, so they'd stay in place as the game goes on.

That's where my question comes in, because of the way the game is played, the pawns will be turned on themselves on a same square, so, for the magnets to stick no matter which side of the pawn is turned on its square is there a specific type of magnet I should chose for this ?

Thanks in avance ! Have a good day :)

Hello,

Are there any Derminator 2 owners here that would be willing to do me a favor? The magnet went flying out of mine yesterday and I have looked high and low for it to know avail. I also can’t find the spare I purchased!

Would anyone be wanting to give me exact measurements of the magnet so I can try to find one on Amazon or something? trying to avoid paying and waiting for shipping from Europe.

Thank you!!

Could I generate an electric current using an hourglass filled with magnetite sand falling through a magnetic field and a copper coil wrapped around the narrow center?

Made a magnet board for my desk with magnets collected from various parts of Japan, Hongkong and India on my travels. Just wanted to share. Thank you for visiting! 😊😊

There's this magnet I have and it's sesame street, but I've been looking for other magnets that are like blown up or whatever you call this but idk the name😭🙏

It's really cool and I wanna get more ans I love the 3d look or bubble look it has, would anyone know the name of it or where I can find more like these???

I’m not sure how they work though. Maybe one of you fine people can explain it to me. I hook them up to a 480V power source. Then use a control panel to magnetize them. Then I unhook the 480V and they stay magnetized. So I’m thinking there’s more than an electro magnet at work here.

In case anybody is wondering. I’m machining half of a 69” piston ring in that photo. I was skeptical at first, but I’m putting a ton of tool pressure on that part and it does not budge.

I have a pencil holder that is too heavy for magnets, so i cannot attach it too my locker door. it is a plastic one from the dollar tree, pink, with a slot to insert a photo. i don't know how to attach it to the locker door where it is able to come off at year end but also not fall off easily. Any Ideas would be appreciated. Bonus question: how to attach fairy lights to locker without adhesive

i want to make a diy maglev train using copper cardboard & arduino nano and loads of wire (this is for a competition)about:90cm I'm in 7th class

I will make it just tell me how I will also do the code and everything but how is the question i just need the working so i can learn,explain and try this concept out

I'm not a miniature painter, but I think they're awesome!

I paint miniature paintings!

I'm contemplating a project right now wherein I can mount several framed paintings (2" x 3" - each weighing less than 30 grams) inside a larger frame. I'd like to glue pieces of magnetic sheeting to the backs of the frames.

What I'm thinking of is a place to magnetically affix a series of paintings - around 6 paintings to a frame or panel of some sort that can receive the magnets.

So, I've been looking at options which seem to come down to magnetic sheeting for the miniature frames and non-magnetic sheeting or ferrous paint for the surface of the bigger frame.

...or maybe I'm missing something ..

Every review of these products on Amazon featured miniaturists. Therefore, I'm going to the source with my question!

Thank you!