cast stack education

[Kiton]

I am starting to plan for a project that I would like to start during my summer holidays and need some help with planning work to a cast iron 4 inch stack.

Gutting it all top to bottom would be straightforward but most of the vertical is still in good shape and I am undecided what is the best approach.
The 2 elbows that join the toilets to the stack are the weak links.

Ironically they are the youngest parts in the system. The stack is 60 plus years and is barely marked, save for the 2 toilet elbows, which I am guessing are about 10-12 years old and look pretty beat up on the insides.

Both toilet flanges are lead peened over brass flanges.

Can I change the lower 1/3 or at worst, 2/3 of the stack for plastic and leave the heavier cast on the top 1/3?
Or is all or nothing?

The elbow on the upper level is joined with MG clamps now.
Can it be pulled and new cast line put in and sealed at the T on the main stack line?
Or is it MG always from this point forward?
I thought these joints were lead chalked, but can that be done on a vertical seam?
If I keep the cast, can I replace the lead sleeve and go to cast toilet flange or is it best to stick with the lead and brass flange?

A lot of questions, sorry, but I am really undecided how to tackle this.


The rotting inside pipe view goes with the unpainted cast elbow.
The painted elbow is in the basement and I have not opened that section of the line yet.

Thank you,

 

[Cacher_Chick]

You buy no-hub cast iron pipe and fittings and install it using banded couplers. Entire buildings are plumbed using this method.

 

[Sponsor]

 

[hj]

quote; is it best to stick with the lead and brass flange?

YOU do not have the experience to work with lead, and unless you find an "old timer", your plumber might not either. I can also tell you that the No-Hub coupling over that casting marker, si NOT sealing the joint.

 

[Kiton]

You buy no-hub cast iron pipe and fittings and install it using banded couplers. Entire buildings are plumbed using this method.

Thanks cacher,
I guess the first question I need to resolve is, am I being foolish to try and save the 60 year old vertical section of the stack?

I am a dept of labor certified all position high pressure welder, if I gut and go ABS I will do the job myself. But cast is a totally different beast than building new install heat exchangers.

If I save the vertical, I will do all the prep work and bring in a plumber with experience in cast iron to replace/connect the toilet elbows, I will replace the galvanized sink drains with PVC up to the stack and let the plumber connect those to the stack.

While I have the walls open, should I gut the entire old cast run? (about 24 feet)

 

[Kiton]

YOU do not have the experience to work with lead......

Fully agree.
The peening of the existing lead to a new brass flange is not a challenge for me with my welding back ground, but old school lead chaulking a joint, I would leave to a pro. As you say, if I can find one!

As a pro, would you bother trying to save the 60 plus year old vertical cast run?

 

[Kiton]

YOU do not have the experience to work with lead, and unless you find an "old timer", your plumber might not either. I can also tell you that the No-Hub coupling over that casting marker, si NOT sealing the joint.

Just a quick update HJ,

You were right about today's plumbers not being up for the work. I have not been able to find a single plumber willing to chalk a lead joint and attach a new branch right from the Tee on the main stack.

The No-Hub coupling installed over the cast marker in the above picture was installed by the biggest, busiest, and said to be best, plumbing and AC contractor in the district. It was done before I bought the house. Needless to say, I do not want to use them on this job.

I like the idea of cast, it is quieter than ABS and as a welder, I can wrap my head around metal more than plastic. The stack runs inside a 6' square box, inside 1 inch thick plaster walls and there is zero noise from pipes. I am hesitant to rip it all out for ABS.

PC4 and oakum is legal in Canada, I do not think it is in the US. I have been given a bunch by an old, retired plumber and he suggested it may be the best compromise if I just change the 2 closet elbows. PC4 is permanent from what I gather, at least with lead, the joint can be reworked. But maybe the pipes will outlast me once the 2 branches are changed.

 

[Cacher_Chick]

The simplest solution might be to pull the vertical sections out of the leaded joints in the stack and replace those. You can install C.I., PVC, or ABS into the hubs of the stack using the proper rubber donut style seals.

 

[Kiton]

The simplest solution might be to pull the vertical sections out of the leaded joints in the stack and replace those. You can install C.I., PVC, or ABS into the hubs of the stack using the proper rubber donut style seals.

Thank you Cacher_chick, I just downloaded the data sheets from Fernco, this looks the best overall compromise. I will replace the closet branch right from the wye at the stack to the WC with ABS. It is about 2 feet at most on both floors.

I have already installed a new toilet upstairs, re-inforced the wooden floorboards with 3/4 plywood, using a Souix Chief flange (it had a smoother bevel than the other brands), peened the existing lead over the flange and it is solid and works well but I really don't trust that piece of cast that has the 2 shielded clamps (which is also the section of pipe shown in the pipe interior picture) in the picture above.

Fantastic suggestion, thank you!

 

[Jadnashua]

Cast iron is still the premium drain system, and hubless pipe and fittings are pretty much the norm that I see (limited experience there, though). The only way that CI is put together is with the hubless, shielded couplers...they work, and work well. If you're going to be doing a lot of it, you should buy the torque screwdriver or wrench to tighten the clamps up, but do not discount them, as they are both viable and meet all codes I'm aware of. CI pipe is still the quietest drain pipe you can install, and can last a very long time.

Using the donut fitting works, but keep in mind there was no strict standard for the ID of the hub, and that is why Fernco makes LOTS of different sizes. Your local supply store will have the more commonly used ones in your area, but it depends on the age, the actual foundry, and then there's a big difference between the 'normal' stuff and the heavy duty version of CI. You need the right size to make the seal or it will either leak, or be a major bear to install, if you can compress it at all enough to make it fit.

 

[Kiton]

Thank you Jim,
The Ridgid 902 and 904 are not cheap! But I have found a few locally and will heed that advise if I use a shielded clamp. My work torque wrench is an old 1/2 drive Proto and would never fit in that small space. Still plenty to explore before project start date, which is the end of July, the venting in the old system (1946) is totally inadequate.

Cast iron is still the premium drain system, and hubless pipe and fittings are pretty much the norm that I see (limited experience there, though). The only way that CI is put together is with the hubless, shielded couplers...they work, and work well. If you're going to be doing a lot of it, you should buy the torque screwdriver or wrench to tighten the clamps up, but do not discount them, as they are both viable and meet all codes I'm aware of. CI pipe is still the quietest drain pipe you can install, and can last a very long time.

Using the donut fitting works, but keep in mind there was no strict standard for the ID of the hub, and that is why Fernco makes LOTS of different sizes. Your local supply store will have the more commonly used ones in your area, but it depends on the age, the actual foundry, and then there's a big difference between the 'normal' stuff and the heavy duty version of CI. You need the right size to make the seal or it will either leak, or be a major bear to install, if you can compress it at all enough to make it fit.

 

[Jadnashua]

Many people 'wing it' when torqueing the clamps up and do not have a problem, doesn't make it right. A pro probably would have the proper tool, and some use them! It's the kind of thing where too loose could disconnect and therefore leak, and too tight could risk either damaging the clamp or giving problems with the neoprene rubber leading to other issues. THere's a sweet spot in the middle, and that's what the torque spec is centered on.

 

[Gib]

As a pro I would leave the vertical cast iron alone. If its not broke don't fix it. The pic of the inside of cast iron pipe looks good. The galvanize branches I agree with replacing. If your code allows PVC, use it. I do NOT recommend ABS. Substandard material in my opinion. Get yourself some capping tools to help protect female threads when removing galvanize threaded pipe that connects to cast iron. Then screw in your PVC male adapter.

You can melt the lead out of any cast iron joint. The lead should only be 1" in depth. Underneath the lead is oalkum, this is what creates the seal and makes the joint solid. The lead just holds the oalkum in place. If your a welder you may have a torch to use to melt out the lead. Then use a PVC cast iron hub adapter to transfer you to PVC. But now you need to pour a joint. Vertical joints are the easiest, horizontal joints require a running rope. Tools you need to pour a joint are: yarning iron,packing iron and a Ladle. Material: white oalkum and lead. Put the fitting in the cast iron hub and start packing in strands of white oalkum with the yarning iron. Typically on a 4" joint I use 4 strands of oalkum but it depends on the oalkum, it might take 5. Use the packing iron and hammer the oalkum in till your left with a 1" space. Basically I yarn in 2 strands and then pack, then 1 strand at a time. Level your fitting. Melt some lead in the ladle and fill the joint. For horizontal, after your done with packing in the oalkum put the running rope on pour spout at the top. Tap running tight against hub and pour joint. Let the lead cool for 3 minutes remove running rope and use packing with hammer and pack lead. Remember you do not need to kill or over do hammering. I install cast iron lead and oalkum joints on a daily basis. Its code where I'm from. I didn't know at the age of 35 I would be consider a "old timer". Its about finesse just like in welding. And yes I have cracked hubs from over packing when I was a apprentice. Its hard to do but it can happen.

No hub couplings, your pic shows 2, 4" no hub couplings. those are your cheap ones. Those take a 5/16" nut driver to tighten. I prefer the 4 bolt no hub couplings. They come in standard, medium, heavy, and extra heavy. I recommend the standard or medium. Fernco, Mifab and Huskey are a few manufactures. I recommend you use no hub adhesive. At the 4 bolt heavy level a 3/8" nut driver will be needed. Again finesse on tightening. The clamp will break. Use a cordless impact or screw gun to snug up and socket or torque wrench to finish. I don't "wing it". I have the rigid torch wrenches and I lost trust in it do to leaks from not being tight enough.

Well I hope this helps.

 

[Reach4]

You can melt the lead out of any cast iron joint. The lead should only be 1" in depth. Underneath the lead is oalkum, this is what creates the seal and makes the joint solid. The lead just holds the oalkum in place. If your a welder you may have a torch to use to melt out the lead. Then use a PVC cast iron hub adapter to transfer you to PVC. But now you need to pour a joint. Vertical joints are the easiest, horizontal joints require a running rope. Tools you need to pour a joint are: yarning iron,packing iron and a Ladle. Material: white oalkum and lead. Put the fitting in the cast iron hub and start packing in strands of white oalkum with the yarning iron. Typically on a 4" joint I use 4 strands of oalkum but it depends on the oalkum, it might take 5. Use the packing iron and hammer the oalkum in till your left with a 1" space. Basically I yarn in 2 strands and then pack, then 1 strand at a time. Level your fitting. Melt some lead in the ladle and fill the joint. For horizontal, after your done with packing in the oalkum put the running rope on pour spout at the top. Tap running tight against hub and pour joint. Let the lead cool for 3 minutes remove running rope and use packing with hammer and pack lead. Remember you do not need to kill or over do hammering. I install cast iron lead and oalkum joints on a daily basis. Its code where I'm from. I didn't know at the age of 35 I would be consider a "old timer". Its about finesse just like in welding. And yes I have cracked hubs from over packing when I was a apprentice. Its hard to do but it can happen.

I was amazed and impressed when I saw one of these joints. I would have figured the PVC would have been melted by the molten lead.

I think most of the plumbers on this forum would use a Fernco Donut to connect PVC into a cast iron hub.

 

[Kiton]

As a pro I would leave the vertical cast iron alone. If its not broke don't fix it........
Well I hope this helps.

Gib,
Some great guidance here, thank you very much for taking the time. I was not aware of this option. I will see if they are code approved here, but if they are UPC approved, I would bet they would be fine here too.

I have the time to order a few parts and do some test joints before I tear in to the walls in a few months and would feel much more comfortable having poured a few joints before "going live" and doing one on the stack. I hand weld (TIG) hundreds of tube ends per heat exchanger. 100% die inspected and then hydrostatic tested by DoL. Hence my preference for things metal.

I install cast iron lead and oakum joints on a daily basis. Its code where I'm from. I didn't know at the age of 35 I would be consider a "old timer".

The variance in work methods from region to region is shocking.
I can understand some changes based on climate, Miami is not Chicago! But I was shocked by how quickly I was turned away when I mentioned pouring a lead joint on a horizontal branch. A few were willing to pour a lead boot and install a brass flange, but that was their limit.

have a great weekend,

K

 

[Jadnashua]

There are tamping tools that make getting a reliable oakum joint and then to ensure the lead is in there properly you may or may not need. There are also some tools needed to pour a horizontal joint. I've seen it done, but never attempted. Since you can reuse the lead, if you have the time, you could practice a bit. Safely melting the lead might also be an issue, and you'll need a suitable ladle as well. Or, if you can snap the hub and fitting out of there, you can use all new hubless pieces. A donut will work with hubless CI, too (double-check, but I'm pretty sure), so no leading required. No new tools, no hot lead, no searching for oakum...