*facepalm* Genius!! Why didn't I think of that!! Still, hardware is quite affordable here mostly because there are tons of Hardware Shops(Excluding Popular ones) and they sell for quite a cheap price. But like I mentioned, Hardware! Electronics come at a slightly higher price but to this country, I would say affordable but you got to hunt for them
Well, if you can't find electronics cheaper than us, I don't know. I think about 90% of the electronics in my parts box is from Asia
I'm not sure actually... are you guys making fun of me? Using electromagnets is rather a problem than a solution :-D
So the electromagnet would be in the DMR.....
No, there won't be enough space in a weapon model, you'll have to put the magnets into the chest piece of your armour. Along with the batteries, which are going to be HUGE.
For example: The electromagnets I have here need 12 V and have a power of 3.8 W. They're supposed to hold 100 N (that's about 10 kg with Earth gravity), but with even a tiny amount of material in between it's going to be a lot less. But you'll need at least two to prevent the rifle from twisting anyways. Lets say these two are enough to hold the rifle, that means 310 mA per magnet, 620 mA total. For 12 V, you'll need 10 NiMH cells, not sure if there's room for size D, so lets take size C instead. These things weigh maybe 60 or 70 g each and have a charge of around 4000 mAh, which would give you a total additional weight of close to one kg to carry around and a runtime of maybe five hours. After that, the rifle will just fall off, unless you have a backup system in place to hold or catch it (which in turn would make the whole magnet thing obsolete). I'm not really sure though if NiMH cells can actually deliver that current, I think the limit is about half an Ampere.
You should also keep in mind that you might end up carrying one hell of a magnetic field around with you. These things can also get HOT (like "you'll burn your fingers" hot!), so you'll probably have to either think of a really good way to cool them, or use completely oversized ones at a fraction of their potential (needless to say, that would mean a further increase in weight and price).
Putting the magnet into the armour piece will also require the switch to be there, which makes things a little complicated. I haven't really thought about that yet. Magnetic switches (reed switches, hall-sensors) are probably not the best choice, because there's going to be interference from the magnets.
Electromagnets don't require a tutorial. Just hook them up to the right voltage and you're done. Polarisation is irrelevant, unless you need the field to go a specific way, which is not the case if you just want to grab onto a metal plate.