I bought a house which do not have commodes, but did have. The Drain is Cast Iron. I tried to install a PVC Flange with rubber seal. It sorta threads in. I got most down except half inch. Would not go any further, nor would it come back out. I finally broke it in pieces with a hammer to get it out. What am I doing WRONG???? I used a little oil to help it along.. but didnt work. HELP..
What kind of “cast Iron” are you talking about? No Hub cast Iron? service weight cast Iron?H CI uncoated? Class 22? since you have no idea the easiest way to make a decent repair is simply buy a “cast Iron” caulked WC flange.
Get some oakum and virgin pig lead and a ladle 4 LBS (minimum) and fill the annular space with this oakum to a depth allowing 1″ and for the molten lead to fill this joint in one pouring. Make sure you have the bolt holes lined up prior to pouring. Make sure this joint is completely packed tight and dry cause if it has any moisture you will get a slight reaction of hot liquid lead flying all over especially back at you.
If your “cast iron” is standard weight OR No hub cast Iron you cold use a Quick set Cast Iron floor flange and tighten it to 60 inch pounds.