I am trying to create a solenoid with a high flux density, but I need the specifications (wire gauge, current applied, etc). The diameter of the core would be preferable around 15mm. The length can be pretty much anything reasonable. I need this for a project that requires a strong repulsive force between this electromagnet, and a neodymium magnet with dimensions 15mm diameter x 20mm length, at a half centimeter distance between the poles. The dimensions of the electromagnet can be flexible. If increasing the diameter substantially increases the strength of the magnet, I am all in for it. Thanks in advance.