Cutting plastic sewer pipe below a concrete slab

[JIMMIE]

I need to replace a toilet flange and about a foot vertical of pipe that is below a concrete floor. There is about 1/4 inch clearance between the concrete and where the flange fastens to the pipe. Is there any kind of tool that is made for doing this. I am considering removing the table from my drill press, fastening a cutoff disk to one end of a long rod and chucking the other end in the drill press to make a saw that will reach down in the hole. Im pretty sur ethis will work but I didnt want to have to disassemble my drill press to do it especially if there is a $10 tool or something made for this purpose.

Jimmie

[hrhofmann]

Can you use a large pwerful hand drill?

[Dean Hoffman]

Try a length of small diameter cable with a loop in each end for handles. I had one for cutting conduit. Example here: >

[JIMMIE]

I dont know if I would get a good cut for putting the new coupling on. I thought about that but I could kind of see that I might mess it up.

Jimmie

[JIMMIE]

Thanks but the pipe has to be cut from the inside.

Jimmie

[Dean Hoffman]

Search for internal or inside pipe cutter. Some here:

[Bob F]

Maybe check a rental shop for these.

[Mikepier]

This sounds like a good application for a Dremel. Just curious why do you need to remove a foot of pipe? Is the flange no good?

[JIMMIE]

Flange is bad and there are a couple of splices below it that have to be removed. It looks like repairs have been attempted on it before. Not enough room for a dremel tool and my hand unless I want to cut it off an inch or so at a time. I may go out to Northern tool and look at some of their cheap drill presses though instead of tearing mine apart.

Jimmie

[Wayne Whitney]

If the pipe is plastic pipe, you could use a tool called a "fitting saver", even though you don't have a fitting in this case. One brand of them is the Pasco Ram Bit.

Basically it is a sharp disc cutter with a positioning disc in front of it, you chuck it into a hand drill. The positioning disc diameter matches the inside diameter of the pipe and guides the tool; the cutting disc diameter matches the outside diameter of the pipe. That way you can ream out the hub of a fitting and reuse the fitting (as long as you don't go too far!).

In your case, you can just use it to grind away the pipe as far as you need to, and then add a coupling. Or you could go all the way back to the hub of the closet elbow. If you are using it on ABS pipe, be careful as gets quite hot, you have to go slow.

Cheers, Wayne

[Colbyt]

Guys, I am fairly sure JIMMIE is a troll.

If he would care to tell me how he plans to glue in the repair for the section he removes I might change that opinion.

Have you thought about that?

Colbyt

[Dean Hoffman]

Internal coupling?

[Stormin Mormon]

Some years ago, I got a call from some friends. The man of the house had fallen in the bathroom, and now the toilet wobbed, a lot. I got one of these. The old flange was cast iron, with lead around it. Lucky for all of us, a couple taps with the 24 ounce framing hammer broke the cast iron. The new flange tightened with allen wrench, and the toilet remounted reasonably well. Took some shims from the paint department to steady the toilet from rocking.

[jimmydahgeek]

WHY? break out some of the concrete, remove some soil, cut the pipe, repair pipe, put soil back in and repair concrete floor. Very small simple job.

[JIMMIE]

I dont understand why you would think that part would be difficult. I will have to dig out a little dirt but that shouldnt be too hard to do once I can pull the pipe out which is what Im asking advice on.

I actually think I have a viable solution to the problem using the drill press to turn a small cutoff blade in side the pipe. Once I get it down inside the pipe I can just slide the drill press around until it cuts out the pipe. Ik now it sounds like a Rube Goldberg way of doing it and I thought someone here would have a better idea. My only real problem of doing it is my drill press is a Big Heavy bench top drill press. Someone suggested using an electric drill instead of a drill press. I was afraid of trying it free hand like that but I may try half way up on the pipe to see how it works.

Jimmie

Jimmie

["<<<]

[JIMMIE]

Ceramic tile, It was installed right up to the edge of the hole.

Jimmie

[JIMMIE]

That was kind of my plan too except I envisioned using a drill press I could slide around on the floor to make sure the cut was neat and square.

Jimmie

[JIMMIE]

I got it done and used a rotozip to do it. I just had to take it out an inch at a time. Doing it this way wasnt as bad as I thought it would be. Trying to do it with a drill with a long shaft on it didnt work. It wanted ti whip around too bad.

Jimmie

[hrhofmann]

Good to hear of your progress.