I have to calculate force exerted on plunger by a solenoid. I need to know the magnetic field generated by the solenoid coil. i can see that online calculator for solenoid force calculation does not consider the practical solenoid. The practical one is layered over another like helix form on the bobbin. For example i have 10 cm long bobbin and i have to wound it for 10,000 turns, then the coil must overlap, like concentric circles (see figure attached)
the bobbin is made of plastic material and plunger is stainless steel. coil wire is music wire. can i get an idea how to calculate the force exerted by solenoid?

 

For starters, look up magnetic field of current loop.

 

Most stainless steel is not magnetic. Maybe use mild steel? The calculation is not simple, but I'd consider asking ChatGPT whilst giving it all the dimensions - length of bobbin (inside end cheeks), diameter of wire (so it can work out increasing diameter of turns), diameter of bobbin (onto which the wire is wound) and the diameter of the plunger (assuming it's axis is in line with the axis of the bobbin. Be wary of the result, it does make mistakes, but it'll give you formulae you can check

 

coil wire is music wire

High tensile steel wire for stringed musical instruments is called 'music wire'. Is that what you have? It is un-insulated so not suitable for a solenoid coil. A solenoid would normally be wound with 'magnet wire', i.e. enamelled copper wire. The enamel provides insulation between adjacent turns and between adjacent layers.

 

@moonlystar1111 :
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I have to calculate force exerted on plunger by a solenoid. I need to know the magnetic field generated by the solenoid coil. i can see that online calculator for solenoid force calculation does not consider the practical solenoid. The practical one is layered over another like helix form on the bobbin. For example i have 10 cm long bobbin and i have to wound it for 10,000 turns, then the coil must overlap, like concentric circles (see figure attached)
the bobbin is made of plastic material and plunger is stainless steel. coil wire is music wire. can i get an idea how to calculate the force exerted by solenoid?
View attachment 355139

Hi,

Just a couple notes...

First, as someone else pointed out, music wire is not insulated it is bare wire unless you use nylon music wire which is not conductive anyway, so either one would not work out at all. Enamel wire is the usual choice here, and get the best one you can find. You do have to make sure the AWG gauge is correct for the expected current though, and because the inside turns are wrapped inside the outer turns, you should use a heavier gauge than normal.

To calculate the force it takes a bit of math and a summation over all the turns, which is not that easy really.

Another note is not all stainless steel is non-magnetically active. You should definitely check it before winding a coil on it. If a magnet sticks to it even a little, that's not a good sign you'll need a different coil bobbin.