fitting closet flange onto waste pipe

I'm trying to install a toilet in new construction. I've cut the pvc waste pipe to floor level but can't fully fit the closet flange onto the pipe - even dry fitting, much less with cement. The waste pipe is 4" and the closet flange (left when roughed in by the plumber) should fit. It goes on a bit but then gets stuck. Is there any way to ease these things on? Thanks.

Sandpaper.
Then when dry-fitted, use PVC primer and glue. Twist the PVC connections a quarter-turn to spread it properly.
The flange should be bolted to the floor, and only the thickness of the flange should be above the finished floor level. Bolt the flange to the floor, and the toilet to the flange (do NOT over-tighten, or it could crack the porcelain).
Good Luck!
Mike

Thanks! I knew the project wouldn't be quite as simple as it seemed.

Be sure the bolt holes are lined up right or you will be cutting it out.

The fit is a tight friction one. If you measure the depth of the fitting, you can get a very good idea how far it will go once you add the cement. The cement acts not only as a solvent, but as a lubricant, allowing you to seat it fully (at least until it sets up!). It is not a glue in the common sense, in that it melts the outer layer, causing a weld, if done right. The same idea of what happens if you are gluing a model together - the glue/cement melts the plastic together.

I'm still having trouble with this one. I realize that it should be a tight friction fit, but I'm reluctant to use cement until I'm sure it will go all the way on, and sanding the inside of the closet flange has produced no noticeable results. Can I only expect the closet flange to go on the waste pipe an inch or so? Should I cut the waste pipe below floor level so the flange can fit on it just that much and still sit on the finished floor?

Keep sanding

they make a flange without a stop that slides over 4" pipe. slide it too the floor then cut extra pipe with an inside cutter.

Measure the inside of the flange from the lower opening edge up to the step (stop). The cement will act like a lubricant and allow you to push it down to that point. It will start to set in about 15-seconds after you push it on, so you only have that amount of time to mush it down. The cement acts by acutally disolving the plastic - softening it, and once the solvent dispurses, becomes solid again, welding the two pieces together. If you carefully measure so that you are sure the flange will go down as far as it needs to without sticking up, then it will work.

But, as noted, since you have a 4" drain, there are several types of flanges that can be used.

What you might want to do is take that piece you cut off (if you still have it), invest in an elbow or another coupling (pretty inexpensive) and make a practice connection just to see how it works. It is almost imposible to seat the coupling on the pipe dry all of the way to the stop, especially after priming (which removes both surface contaminants and makes it rougher) unless you have the cement on it to act as a lubricant.

You could spread some vasiline on it, slide it on to check the fit, then be very careful to clean all of that off before gluing it together - use a good solvent and/or soap to clean it up then the primer.

It is intimidating the first time you do it. Unless there is a defect in the fitting - like a knob of plastic sticking out - it will fit. My unprofessional experience.

flange

The pipe was never "designed" for the flange to go into it, although it is often done. The professional way is to get the proper flange that fits over the pipe. It will/should go down as far as necessary, unless the pipe was installed too high in the floor and there is not enough pipe to allow it to slide down.