Foul waste vent pipes.

[plumbers mate]

I think this is called the foul waste vent pipe.
Not sure about proper name. There used to be an outside toilet building in the back yard and it had a cast iron pipe from the nearby drain. This toilet was removed about 20 yrs ago and the vent pipe is in the way. I want rid of it. (There is a vent from the waste of the indoor toilet of course)
Now - How do I get rid of this 4ins diam 9ft tall cast iron pipe?
If I don goggles, hard hat, boots and gloves and clout the pipe near it's base with a *big* sledge hammer, will the pipe shatter so that I can break it up? Would I need to put a dust sheet around it to avoid too much flack flying around the yard (bearing in mind I've just had the windows done and don't want a piece of CI flying through the glass or decapitating my runner beans).
It has a good strong bracket holding it to the wall so hopefully wouldn't land on the hard hat which wouldn't really save the head underneath.
The hole left in the yard would be filled by the patent method of a plant pot full of concrete (it's a victorian concrete YARD so concrete is the proper material - limeys!) as was done when the netty was taken out.
A helpful friend said use a hacksaw - he'd never heard of cast iron pipes and though they were all plastic - some friends make me feel so very old.

 

[inwood]

Get an angle grinder with a metal cutting disc, some goggles and create your own fireworks display. Seriously though an angle grinder will cut through it very quickly and although you probably won't be able to get all the way round it (unless you've got a friend with a 9" angle grinder) you'll then be able to use a lump hammer and cold chisel on the last bit since cast iron is fairly brittle.

 

[Andrew Bodenham]

I second Inwood's advice. Smacking it with a sledgehammer would work, but with all the flying debris problems you've already thought about. Cutting up with an angle grinder would be a much more controlled way to proceed.
Don't know what the scrap value of CI is, but probably worth a trip if you've got a scrappy nearby.

 

[Lime]

I wouldn't try and smash the pipe.
Cast iron is brittle but if in compression is many times stronger than steel.
You are making work for yourself.
The end of the metal pipe is almost certainly run into an ordinary clay 4" pipe (which will usually be broken around the collar) so I'd just pull out the clout nails holding the bracket of the pipe onto the wall and lift it out.

Cutting the pipe with an angle grinder cutter would be very dangerous.
cast iron is not like steel, it is a lot harder.
The blade would not go right through the pipe (because the pipe is bigger than the blade) and it would almost certainly catch the cutting blade.
Broken cast iron is very sharp and could cause serious injury if propelled through the air, particularly if the blade breaks off at the same time and the cutter become unbalanced.
Don't do it.

 

[chuckey]

As said the cast iron pipes are normally made in sections with built in collars and brackets. The joints are normally very solid with age so they are the toughest bit to break. the fixings are normally soft, big nails going into rotten wooden plugs, so a high stack pipe can be pulled from a wall and will fall down as one piece, smashing the top of the saltglaze sewer pipe (if not already broken).
I would not use an angle grinder, you will not be able to cut right through the pipe, but a notch would be a useful point to start a break at. Use a lump hammer, as far as I remember there is not too much shrapnel. Just go for breaking off sections you can carry (3' ?).
Could be an idea to stuff a rag on a piece of string down the pipe to a point lower then your nominal break point to stop bits rattling down the drain and working their way into your sewage system.
Frank

 

[plumbers mate]

Thanks for the advice.
I'm glad I checked before letting my frustrations out with builders who don't want work by clouting the pipe with the 7 pound hammer!
I thought I was onto a winner with the collar/bracket but it's in really strongly -there was an ordinary bracket higher up which fell out when I tried to hang a bird food holder on it in the winter, but the collar one looks well embedded. I don't want to have a collapsed back yard wall to deal with - I am repointing it (OK badly, but it will be painted and it's being done with love) and that is one of the reasons for getting rid of this darn pipe now. Rebuilding the wall would have me running scared.
What is the weight of such a pipe likely to be? It's about 9ft high/long.
My friends are the sort who can wield a pen and quote Rouseau but wouldn't know an angle grinder from a belt sander and be as much practical use as the proverbial edible fireguard, starting a discussion on some obscure thing at the wrong time, so I am on my own with all this.
My B&Q Over 60's Diamond Card should come up with an angle grinder on wednesday.

 

[plumbers mate]

On second thoughts, re-reading Lime's comments about "danger" I think I'll work on the collar and try to get it out of the wall and see what happens. I do have an apprehensive approach to power tools.
It has also occured to me why some of the houses which have lost their pipes is because some of the netties in the street were ash closets. Trust me to get a posh house with a proper outside facility!

 

[piper]

as much practical use as the proverbial edible fireguard

Never heard that one. I thought the proverbial useless thing was a chocolate teapot. An edible fireguard could actually be quite good at deflecting sparks etc. until it was eaten.

 

[Penners]

PM - I echo Lime's suggestion about trying to separate the cast iron pipe from the underground saltglazed, if you can. It's much the best solution. Get your Rousseau-quoting friends to help - tell that that they may have been born free, but now they're in chains until the job's done.

You mentioned plugging the hole with a concrete-filled plant pot, from which I infer that you will just pop the pot into the hole. If you can, I suggest you try to make rather a better seal than this, otherwise you risk getting foul drain pongs coming back up the pipe and sneaking out around any loose-fitting insert. You can buy expansion bungs from a plumber's or builder's merchant that will do a good job. This sort of thing is very effective:

 

[plumbers mate]

Good point about the pongs!
When I removed the old toilet I sealed the hole with a concrete filled plant pot and concreted a piece of slate on top - however, that is Ok because my raised flower bed (AKA "the garden")has been created on top so any odours are absorbed by 24 ins of soil.
Now --- I would like the one with psychic powers top confess.
On Monday, the collar half way up the pipe was rock hard into the wall and the pipe was solid, wouldn't even twitch when pushed.
Today the whole thing moves when pushed. Who has sent out the vibes to do this and, if they are going to do it again, can they let me know so I can stand by and give an extra hard shove when they do it?
Thankyou.
PS. We always said chocolate fireguard, never chocolate teapot when I was a bairn.

 

[Penners]

Today the whole thing moves when pushed. Who has sent out the vibes to do this

I'm afraid that's probably me.

As Mrs P will confirm, I have only to look at/think about/talk about something and it immediately becomes unstable/falls apart/disintegrates/explodes. Just think yourself lucky that my influence in this case has been at the mild end of that scale.