I have perhaps a thousand pounds of steel scrap to take to one of the local recyclers, but a decent share of this is in electric motors and transformers (the motors are multi horsepower). I think that means there is separate value in the copper content, and also that the steel content is likely silicon steel which perhaps they don’t want mixed in with the commoner steels (but then maybe they don’t care about that).
If I am interested in getting the job done quickly, is there a risk they will reject the motors and transformers because turning them into “just steel” is more difficult?
On the other hand, if I am interested in getting the most money, how much more can I get by separating the copper somehow?
They’re unlikely to reject the material, but you will probably get a lower price per pound for mixed metals. You may do better separating the motors and transformers and give you a better price for those than the other scrap. For instance, they’ll pay a different rate for cars based on weight than for something that is all scrap iron. A couple of months ago the price of copper was pretty low and it may not make much difference in what they’ll pay by weight anyway. If the motor and transformer cores can be rewound they’ll be worth more, but you still won’t get a lot extra for them.
Transformers, generators, and motors are called transformer scrap. Separate them from your other scrap. It will bring more then steel & less then copper. This is the easiest way to deal with them.
Unless your time is worth less then about $5.00 an hour, it is not economically feasible to separate the copper from the steel. I have tried this, as has Uncle Sugar. Seriously the US government has done studies on this. I know, I know, but they did and they discovered that to equip a shop to cut the copper out of transformers and motors was not worth the time.
The other scrap should be sorted at least a little. Steel, cast iron, aluminium, and other yellow metals should be separated from each other. Each of these categories can be sorted as well. Unless you plan on becoming a “scrapper” doing a lot of scrap this 2nd sort is not worth the effort.
So to recap, sort the transformer scrap from the rest and sort the various metals from each other. Haul them in in separate containers, or at least have them in separate piles in the truck. Purity counts for a lot. No steel in the aluminium, etc. I would not cut steel insets out of aluminium you will get less $$ for it, but not enough less to make it worth it to you.