There are clear benefits of using toroids. Two of the most important are: 1) these are a high quality product that requires little turning; 2) the item is self-shielding (you do not need any metal casing to contain the field). The two benefits are found when someone has the proper toroids: that means materials, size, wire, and cores. If your toroid(s) isn't working to full capacity then there are things you can do. It is possible for people to construct or tinker with toroids on their own. You don't have to be afraid to work with these electrical pieces. The first thing to do before exploring your own toroids is to understand the distinctions between different parts, materials, and more. There is a lot of complexity when it comes to these items, so if you do not know what you are doing then you should refer to a professional.
1) Make sure that you have the right core is in your piece. There are two different types of cores found in these products: ferrite and powdered iron. Know what frequencies you are working with because ferrite is used for narrow-band RF circuits (usually this works up to 10 MHZ). If you are working with higher frequencies then you will want a powdered core.
2) Be carful of saturation. As mentioned above, different cores work at different frequencies, so if you choose wrong than overheating becomes an issue. Another issue of saturation is unwanted and unneeded harmonic currents. The cross-sectional part of the core also affects the saturation threshold of the piece. The amount of turns a coil makes, as well as the voltage and current, are what will cause your piece to saturate.
3) Toroids have numbers assigned to them, and those numbers can get rather confusing for those who don't know them. There are charts online that will help you to understand the distinctions between the numbers. Learning what the numbers means will help you to understand what the toroid is supposed to do.
4) Winding the coil is not difficult, but you must take your time. Some people have different ways of starting, but in essence you want to wind the wires next to each other and not on top. You want to try and keep the wires tight around the core. It will still work if not tight, but if it is tight it'll work better. Try and get 7 to 13 loops around the coil, and also make sure that they wires are evenly spaced out.