cast iron joining

[conor]

hi everyone.im starting a new job where i might have to maintain old cast iron pipework.but because im a fairly young plumber ive never worked with cast iron. ive been doun some research and can only really get info from america.so i dont know if it applies here. they say that oakum fibre is packed into the joint and then molten lead poured over.when the lead is nearly solidified its "worked" into the joint as it shrinks a little when solidifying.was/is oakum used here.or is oakum the same as flax/hemp.any advice or tips would be helpful thanks a million lads

 

[mrlennie]

Dont know anything about it myself but you could ask down at your local plumbers merchants what they use or i think there is a website called heritage house they maintain old houses look them up.

 

[Guest123]

There are a few ways to join cast iron pipework. The traditional way is to use a caulking tool to insert twisted rope yarn into the socket (faucet) and then pour melted lead into it until flush with the top. This is considered quite dangerous these days and with the lead not environmentally friendly. Molten lead is dangerous and can explode if water enters the pot. The second method is to use a cold caulking compound known as PC4AF which is twisted and caulked into the joint like rope yarn, but it is kept wet. It sets like cement and is very strong, but wear a mask due to the dust from the tin! The third method and what I consider the best is to use a Timesaver coupling. This is a rubber gasket that is secured and tightened to make the joint with a cast iron coupling and M10 bolt using a socket spanner. Very strong and watertight and is easier than the other two methods on horizontal pipe runs. If you want full instructions on these methods, PM me.

 

[kingkenny]

google search timesaver,you can download their catalogue in PDF for more info.

 

[ecowarm]

Hi Connor

It does depend on the cast iron pipework's use, it could be supplying mains water, tank fed water supply or even an old heating system. The answers above relate to rain water or soil.
For water supplies and heating use a mechanical coupling like http://www.vikingjohnson.com/pdf/design_english.pdf on page 6 + 7 of the download.

 

[justlead1]

Hi Another alternative is lead wool. Often used where water present or on horizontal joints. If you are pouring lead in joints yarn well the 2/3rd of the socket and one third lead, when cool caulk it with an iron, this take up the minute gap left by contraction of the molten lead when cooling.

 

[Bernie2]

Err!

Done loads of it!

Mostly 3/16th soil or Stanton. Simply can't remember if I did any water mains stuff, but same idea.

You need a buzzer and pot to melt the lead in. A ladle to get it out with. Goggles of the right type, mask and gloves.

If you get water mixed in with molten lead it explodes all over the place, hence the goggles and its hot so it will burn through cheap safety goggles. Molten lead also gives off fumes, so mask. It also means things get hot, so gloves.

Basically if its wet or raining don't do lead jointing. If its been raining and the collars may be wet, wipe with a bit of meths, you can drink the rest

Actually it makes you sick as a dog if you do, tried it!!

The alccies mix it with cider, if your wondering.

Bit like trying to smoke Plumbers hemp. That just burns so fast your left with a roll up stump in your mouth in about 2 seconds flat and it burns your nasal passages if you do manage to get a drag. No! you don't get a trip, you get a headache and a burnt nose that hurts inside like mad. I would not even try it if I was you.

The stupid things you do when your young???

Anyway!

If the collar is horizontal, obviously the lead would run out if you tried to pour it. So you need something to stop it. What is commonly used is something called a squirrel tail, which is just a piece of rope usually asbestos or probably one of the calcium derivatives now. It fastens around the pipe and leaves a space at the top to pour the lead in, you can also get a clamp that does the same thing.

Just put the squirrel tight around the pipe, tap it against the socket to keep the lead in.

Then after first caulk yarning the joint, fit squirrel then pour in the lead. When cool remove squirrel and using a curved blade off set caulking iron "Bump" up the joint, using a heavy hammer, but keeping in mind that if you hit it too hard you can split the collar.

Don't forget caulking irons come in many blade widths, try and get one that suites your pipe collars lead caulking width when the next pipe is in the collar. And a narrow one for caulking the yarn.

Then you can finish off with a flat bladed chisel to cut off any straggly bits and make the joint look flush with the top of the collar.

Sounds a lot to do but isn't really. Just a bit dangerous and you need to keep concentration.

Try the Lead Development Association site for a better idea.

 

[stevetheplumber]

ive done hundreds of these no goggles or mask and usually a bit of rag for holding the ladle how times change doing them suspended in a bosuns chair was fun as the pot was lowered on a rope over your head

 

[Bernie2]

Must admit Steve,

I added the bit about Health and safety for modern Plumbers, we had no idea what it was. And we did as you say work without any safety gear usually.
I never liked bosuns chairs or cradles.

A mate of mine went over a roof edge on a chair while his mate stayed on the roof to haul him up. It was only after he got back on the roof his mate told him he had been the docs because of blackouts he had been having.

Crazy days.

 

[WHPES]

Done a bit on cast iron heating system for a large hotel. Basically you need to leave it well alone and pray it doesn't start to leak!

It's pre war and made up from 4" spigoted sections. If any of it fails it will be replaced with flanged steel sections.

If you need to make new connections, you drill into it with a rotabroach and use special saddle clamps with a threaded outled to take low carbon steel or ductile iron pipe, a bit like a strap on boss for a soil stack.

If you haven't had much training or experience in larger bore pipework, don't attempt it yourself, I would speak to a pipeline company and keep their number handy so you can sub it out.