Toilet abs stub

[robertp777]

Can anyone tell me the proper way and what tool is best for cutting the abs stub to the proper length to attach the toilet flange. I need to install the Toilet, but I first have to deal with the ABS stub through the floor. It is on a second floor and I would have to cut below the floor level. I want to get a straight and level cut and do not know if there is a proper tool to do this or just what the proper proceedure would be.

Thanks Robert

[Spaceman Spiff]

I use a dremel tool with a flat wheel burr or a cut off wheel. Cut off the top of the pipe above the floor with your regular saw so that it is level. Then use a pencil or grease pencil to mark a level line inside the pipe by holding the pencil and running your finger at the top of the pipe cut. Then use this line to run your dremel around on the inside of the pipe cutting to the outside. Be quick so that you minimize the melting and clean off the burrs.

It doesn't need to be exactly level and sometimes I do it in two dremel cuts if I can't get the pencil tip down the tube far enough. The first cut will get it below floor line, then the second will get it to just the right length. I can do a set of cuts in just a couple of minutes.

[GrumpyPlumber]

Home Depot carries an "I.D. cutter" (Inside diameter), also known as a ram bit .
It's a tool that almost resembles a propeller attached to a 3/8" hex shaft that can be put into a drill.
It's perfect for toilet flanges that need to be cut out when the floor and the ceiling below are closed ....then you attach a coupling with a female flange(dry fit it first to get your height).
One IMPORTANT note....make sure the pipe directly below the current location isn't a 90 elbow...you can't cut it...it has to have a straight run of vertical pipe running out.
Also...if this is new piping...I usually leave the toilet stub dry, if I don't know what the thickness of the floor is going to be (example...if the contractor is undecided on tile or linoleum, or might be raising floor height)...so I can make a measurement after the floor is done, pull out the 3" and cut it to the right length.

[Spaceman Spiff]

What??? A tool I don't have? Time to go buy one...