The saddle is PVC and held on with two U bolts. Put the clamp in position, on the top side if putting it on a horizontal pipe. Mark around on the inside of the hole in the saddle. Use a new 1/8th drill bit you might need several, and make a series of holes almost connecting around the hole you marked. When you have them all drilled, elongate them to connect them, When most of them are connected tap on the plug until it begins to break out. Try and catch it before it falls into the pipe. You can drill 1 hole in the center and put a screw in it to hold onto. Put a bead of plumber putty around the hole where the saddle will compress it. Put the U bolts on and tighten.
With a compression mission ring
Yes, it is done all the time
Downstairs? First floor with a basement or in the basement? If first floor with access in the basement or crawlspace, no real problem. PVC, just cut the pipe and install a T. Cast iron, you can use a Saddle Clamp made for this. Looks like a PVC T split length wise and held to the cast iron with two U bolts. If adding a bath in the basement, you will have to bust out the floor, add the drain and replace the cement.
Where? What is your question?
By cutting in a cast iron Wye so the flow enters the sewer line (soil pipe) at a right angle
from the hub to the spigot
You remove the existing tub shoe and related fittings and install a new assembly. In some cases a reciprocating saw will be needed to cut the shoe flange located inside the tub
Galvanized pipe for water and drain lines. Cast iron pipe for main drain lines.
Both and but normally a master plumber would fix the problem by removing the existing drain lead/copper /cast iron and install a new drain and remove the membrane to the existing slab water proof the slab with either roof cement or flashing cement then install 4 PSF sheet lead over the drain flange/clamping gravel stop collar and you will now have a leak proof job
Yes, but PVC creates problems
If it is "rusted out" you do not repair it, You do replace it with XHCI
You can buy the new cast iron flanges, with the expandable O rings that push into the pipe or you'll have to do the old style or pouring lead onto a cast iron flange. The latter option should only be done by professionals.