On 19 Apr 2004 19:36:48 GMT, (POPPYPLANK) wrote:

Hi Vic. Thanks for the detailed answer, I very much appreciate it and
it's looking at this point that it will be the roadmap I will be
following.


Your best and easiest path to success is get a group of Torch Blades (trademark
of Milwaukee) and a Sawzall.

Do you recommend against a snap cutter?

The Torch Blades cut cast iron like it was just steel. It may two or three
blades to do both cuts. I could do it with one but I have been using a
sawzall for 30 plus years.

You have indicated that you have the upper portion of the stack supported.

Yes, a double chain, turnbuckle arrangement attached to ceiling joists
at one end and the riser clamp (gripping the 4" cast iron riser) on
the other. However, this arrangement was only intended to relieve the
load at the site on the cast iron I had originally intended to cut a
3" hole. I'm not sure I would trust this arrangement to both bear the
full weight of the riser and offer sufficient lateral stability to the
riser while removing a whole section of it.

What do you consider sufficient support? Do you build a, say, 2x4
framework that supports a riser clamp (clamped to the CI riser) from
the floor?

I dont recall if the stack is 3 or 4" but get the correct Wye either 3 x 3 or
4 x 3

4"

I'm thinking the correct Wye is a "waste T". The leg that will receive
the PVC opens perpendicular to the legs that will receive the cast
iron, but a downward sweep is molded into the this perpendicular leg.
Are we thinking of the same fitting?

and add at least 6 " of PVC to both of the runs of the Wye and add about
1/4" to the total developed length and make your two cuts.

Ok. So the length of the cut will be the total length of the PVC
assembly plus 1/4".

While you are at home cheapo or wherever you shop for plumbing stuff pick up
two Fernco's for the stack diameter. Not No-Hub. Not some other cheap
junk...Make sure the name Fernco is on the rubber sleeve.

I will make sure I get Fernco
..
A Fernco is a Rubber Sleeve that will fit over your cast iron (take note of
whether on not your cast iron is XH or not).

I don't know how to distinguish XH from whatever else (SV?) there is.
I ground off much of what's embossed on the exposed riser because, as
indicated earlier in this thread, I had originally planned to install
a PVC saddle T with gasket and I wanted to insure a good seal. But it
seems that XH would have a larger OD than the SV.

I guess I'll just have to measure the riser diameter and compare it to
the available Ferncos.

You have now assembled your PVC Wye with a 6" piece of Sch 40 PVC glued into
each run of the Wye.

You have sucessfully cut out the proper length of cast iron leaving at least 3"
of cast iron sticking out of any fitting so you can slide the fernco over the
cast iron.

Ok.

You now drive back to the hardware store and get the cast iron soap I forgot
above.

Damn! I knew I forgot something!

Cast Iron soap is a very slimey substance that allows rubber to slide over PVC
and cast iron.

Liquid dish detergent works in a pinch

Ok.

Open the stainless steel clamps on the
fernco's ...not completely leave the last little bit of the slotted band
engaged in the screw portion of the band.

Ok.

soap the inside of the fernco with the slimey cast iron soap... get the entire
insides of the fernco semi soapy...apply some soap to the outside of the PVC
pieces sticking out of the runs of your Wye.

Ok.

Slide the Fernco over both ends of your PVC assembly until the ends of the
ferncos are about 1/2" past the ends of the PVC.
You want about 1/2" of white plastic sticking out of both ends of your PVC
assembly

Ok. If I'm reading you right, you're saying that the Ferncos are to be
pulled all the way down over the PVC at each end till about 1/2" of
PVC is left exposed at the ends.

Soap enough of the cast iron to accept 1/2 of the length of the Fenco plus
about 1" longer for slop.

Ok,

Install the PVC assembly in the opening in your cast iron stack...now it gets
to be fun slide the lower Fernco over the cast iron and tighten the lower band
only...not bulls ass tight just yet...then holding down on your PVC assembly
raise the upper fernco and tighten (see above bout the bull).

Ok.

Now we have to line up the Wye with your new stack ...since I am not there I
cannot advise you step by step...but you will need a 3" PVC Street 45 to plumb
the outlet of the Wye.

I'm not sure I understand what you're telling me, here. Are you saying
that I should temporarily install the Street 45 into the Wye outlet so
that I can get a fix on how plumb the assembly is, and adjust
accordingly? If this's right, I should probably stick a 2' or so
length of PVC into the other end of the 45 to put a level up against.


Once you have the new stack plumb*; it is time to tighten the bottom band.
Now we very slowly allow the upper fernco to accept the weight of your
existing soil stack.

I'm not clear how that's done. You seem to be implying that the
support that's initially erected for the CI riser is constructed such
that it can be gradually diminished, allowing the riser to actually
move down about 1/4". How do you usually accomplish this?

tighten the uppper fernco upper band when the weight has been accepted

Ok. But I hope you will further comment on how I might accomplish
letting the CI riser settle onto the Wye. I take it that the PVC Wye
can bear the weight of the riser column.

Has it ever happened to you that that 1/4" of riser movement has
translated into consequent problems above..like, for example, a roof
leak?

double check plumb on the new stack and tighten inner fernco bands.

Ok.

that is the proper and code accepted way in just about any place in the US
where PVC is accepted as a listed material

Damn I'm tired just typing about it

Thanks for the detailed proceedure, Vic, much appreciate it. It's
looking like this is what I'm going to be doing.

Al