Hey there. If there's a ton of iron, it can be overwhelming, so you want to keep the machine quiet, fast, and stable. Don't worry too much about super depth, but concentrate on plucking signals from the junk. These are my settings that I use for heavy trash & iron.
Lets start with your disc, try 8 to knock out the tiny bits of junk and most nails. Run 2 tones, you'll get a grunt for iron and a good tone for everything else. That will save your sanity.
Now your sens, start on 90, and TX at 3, but you can run it on 2 if its too chatty. You can increase the sens from there as long as the machine is stable. Back off when you hear the chatter.
Reactivity on 3, silencer on -1. Keeps the machine quick and still gets above average depth.
Iron volume 1, because you don't want to hear it. It will still make a faint grunt in the background.
Freq. 17.6
Audio response 5, the good signals will scream at you.
Overload 0
Notch 97-99, this will knock out big, deep iron that often fools the machine.
I hope this helps. Save this one as your custom trashy program. Good luck with it. Let me know how you like it.
Mossy99.