Use less than 30 p.s.i. to reduce the amount of "splattering".
Set the rod to operate at 1/2" below soil surface.
Center the blade on the hub, so that it is concentric when it turns. Place the knife top up to the coulter blade; so that the knife and coulter blade just slightly contact each other at the tip. Then as the coulter blade rotates up the knife, you want to have a gradual gap between the knife and coulter blade. Also the knife needs to be centered side to side on the coulter blade.
In some conditions a knife scraper is needed to keep the residue from "dragging" up on the fertilizer knife. 2970-133