My son's next project is to install two new cast iron drainpipes. The
old ones were rusted through and dangerously detached from the sandstone
wall. It's about a 14 foot straight vertical drop and they take the
rainwater from the roofs in a neighbour's garden.

We think the pipes are original and well over 100 years old and, having
seen the price he has paid, I think we want to do as good a job as
possible so that these last another 100 years and also because ladder
access to the wall is quite difficult.

The pipes come primed with what is described as grey oxide primer.

I would normally paint them with my favourite 2-part epoxy primer and
then some decent top coat, but maybe there are more standard and easier
paints to apply. Also, should we attempt to paint the inside of the
pipes? The old pipes rusted from the inside. The original "hoppers" at
the top of the pipes are in reasonable condition, presumably because
they were painted inside and out. We are going to re-use them.

Has anyone done this sort of thing and can give any advice or points to
avoid?
--
Bill

In article ,
Bill writes:
My son's next project is to install two new cast iron drainpipes. The
old ones were rusted through and dangerously detached from the sandstone
wall. It's about a 14 foot straight vertical drop and they take the
rainwater from the roofs in a neighbour's garden.

We think the pipes are original and well over 100 years old and, having
seen the price he has paid, I think we want to do as good a job as
possible so that these last another 100 years and also because ladder
access to the wall is quite difficult.

The pipes come primed with what is described as grey oxide primer.

I would normally paint them with my favourite 2-part epoxy primer and
then some decent top coat, but maybe there are more standard and easier
paints to apply. Also, should we attempt to paint the inside of the
pipes? The old pipes rusted from the inside. The original "hoppers" at
the top of the pipes are in reasonable condition, presumably because
they were painted inside and out. We are going to re-use them.

Has anyone done this sort of thing and can give any advice or points to
avoid?

Needed to replace a friends cast iron guttering. A builder gave
us a tip - use round PVC rainwater guttering (you can get some
with couplings which look a bit like the old cast iron ones),
and then paint the PVC badly with too much gloss paint (runs,
drips, etc). It really does look just like the original.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On 06/07/2012 11:40, Bill wrote:
My son's next project is to install two new cast iron drainpipes. The
old ones were rusted through and dangerously detached from the sandstone
wall. It's about a 14 foot straight vertical drop and they take the
rainwater from the roofs in a neighbour's garden.

We think the pipes are original and well over 100 years old and, having
seen the price he has paid, I think we want to do as good a job as
possible so that these last another 100 years and also because ladder
access to the wall is quite difficult.

The pipes come primed with what is described as grey oxide primer.

I would normally paint them with my favourite 2-part epoxy primer and
then some decent top coat, but maybe there are more standard and easier
paints to apply. Also, should we attempt to paint the inside of the
pipes? The old pipes rusted from the inside. The original "hoppers" at
the top of the pipes are in reasonable condition, presumably because
they were painted inside and out. We are going to re-use them.

Has anyone done this sort of thing and can give any advice or points to
avoid?

I wouldn't bother trying to paint the inside. You are not going to be
able to achieve a long term high integrity coating. Most of the time
they will be dry inside, and even when they are wet, rainwater is fairly
pure even in an industrial area. (I'm assuming you don't have sea spray
landing on the roof). You should easily get another 100 years life.

I have some original hoppers to put back some time. Like yours, they
have plenty of "meat" left, but I doubt if they were painted internally,
at least not regularly. A typical corrosion rate for bulk ferrous
material even in fairly adverse conditions is 1 mm per 100 years. Even
for things like anchor chains and mooring rings submerged by seawater
every tide, you are struggling to get 0.1 mm per year.

On Fri, 06 Jul 2012 11:40:32 +0100, Bill wrote:
We think the pipes are original and well over 100 years old and, having
seen the price he has paid, I think we want to do as good a job as
possible so that these last another 100 years and also because ladder
access to the wall is quite difficult.

How thick are the walls of the new ones compared to the old? I expect
that's what matters to the longevity (as you say, they'll likely rust
from the inside out)

In message om,
newshound writes
On 06/07/2012 11:40, Bill wrote:
My son's next project is to install two new cast iron drainpipes. The
old ones were rusted through and dangerously detached from the sandstone
wall. It's about a 14 foot straight vertical drop and they take the
rainwater from the roofs in a neighbour's garden.

We think the pipes are original and well over 100 years old and, having
seen the price he has paid, I think we want to do as good a job as
possible so that these last another 100 years and also because ladder
access to the wall is quite difficult.

The pipes come primed with what is described as grey oxide primer.

I would normally paint them with my favourite 2-part epoxy primer and
then some decent top coat, but maybe there are more standard and easier
paints to apply. Also, should we attempt to paint the inside of the
pipes? The old pipes rusted from the inside. The original "hoppers" at
the top of the pipes are in reasonable condition, presumably because
they were painted inside and out. We are going to re-use them.

Has anyone done this sort of thing and can give any advice or points to
avoid?

I wouldn't bother trying to paint the inside. You are not going to be
able to achieve a long term high integrity coating. Most of the time
they will be dry inside, and even when they are wet, rainwater is
fairly pure even in an industrial area. (I'm assuming you don't have
sea spray landing on the roof). You should easily get another 100 years
life.

I have some original hoppers to put back some time. Like yours, they
have plenty of "meat" left, but I doubt if they were painted
internally, at least not regularly. A typical corrosion rate for bulk
ferrous material even in fairly adverse conditions is 1 mm per 100
years. Even for things like anchor chains and mooring rings submerged
by seawater every tide, you are struggling to get 0.1 mm per year.

Thanks, that's useful info.

I went round there in the rain today. I had assumed these drained into
soakaways, but the water flowing in the absence of the pipes has washed
away some of the earth and exposed what looks like an old, blocked
earthenware drain system I have no idea where it goes as it's well away
from the house drains, a surveyor friend thinks it goes to a central
"sink"..
We may have to excavate amongst the huge old roots to try to trace and
or replace this. Son thinks this is becoming another next year job.

The rainwater is away from the sea, but there are huge trees all around.
In the rain today one of the house drains has spewed forth a large load
of decayed growth from the house roof. We might have to buy some litmus
paper to test it. :-)
--
Bill

Chuckle, they still click when the sun comes out though!

I do recall some years ago seeing a very old building near me with people
putting in new what I thought were cast iron downpipes, looked just like it
but they were in fact some form of heavy plastic stuff. Even the hardware
was chunky but plastic .

This must have been ten years back. I guess it depends if you really want
the real stuff or imitation old stuff!

From the original poster I am assuming the pipes are already purchased. I'd
definitely inspect them inside just in case they have been left to rust, but
if they are primed inside, I'd not do much else. They will outlast you.
Brian

--
--
From the sofa of Brian Gaff -

Blind user, so no pictures please!
"Andrew Gabriel" wrote in message
...
In article ,
Bill writes:
My son's next project is to install two new cast iron drainpipes. The
old ones were rusted through and dangerously detached from the sandstone
wall. It's about a 14 foot straight vertical drop and they take the
rainwater from the roofs in a neighbour's garden.

We think the pipes are original and well over 100 years old and, having
seen the price he has paid, I think we want to do as good a job as
possible so that these last another 100 years and also because ladder
access to the wall is quite difficult.

The pipes come primed with what is described as grey oxide primer.

I would normally paint them with my favourite 2-part epoxy primer and
then some decent top coat, but maybe there are more standard and easier
paints to apply. Also, should we attempt to paint the inside of the
pipes? The old pipes rusted from the inside. The original "hoppers" at
the top of the pipes are in reasonable condition, presumably because
they were painted inside and out. We are going to re-use them.

Has anyone done this sort of thing and can give any advice or points to
avoid?

Needed to replace a friends cast iron guttering. A builder gave
us a tip - use round PVC rainwater guttering (you can get some
with couplings which look a bit like the old cast iron ones),
and then paint the PVC badly with too much gloss paint (runs,
drips, etc). It really does look just like the original.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On 06/07/2012 11:40, Bill wrote:
My son's next project is to install two new cast iron drainpipes. The
old ones were rusted through and dangerously detached from the sandstone
wall. It's about a 14 foot straight vertical drop and they take the
rainwater from the roofs in a neighbour's garden.

We think the pipes are original and well over 100 years old and, having
seen the price he has paid, I think we want to do as good a job as
possible so that these last another 100 years and also because ladder
access to the wall is quite difficult.

The pipes come primed with what is described as grey oxide primer.

I would normally paint them with my favourite 2-part epoxy primer and
then some decent top coat, but maybe there are more standard and easier
paints to apply. Also, should we attempt to paint the inside of the
pipes? The old pipes rusted from the inside. The original "hoppers" at
the top of the pipes are in reasonable condition, presumably because
they were painted inside and out. We are going to re-use them.

Has anyone done this sort of thing and can give any advice or points to
avoid?

If you had asked before buying, I would have said buy the aluminium
copies of cast iron. They look the same, don't rust and are a lot easier
to carry up a ladder.

Colin Bignell

On Jul 6, 11:40*am, Bill wrote:
My son's next project is to install two new cast iron drainpipes. The
old ones were rusted through and dangerously detached from the sandstone
wall. It's about a 14 foot straight vertical drop and they take the
rainwater from the roofs in a neighbour's garden.

We think the pipes are original and well over 100 years old and, having
seen the price he has paid, I think we want to do as good a job as
possible so that these last another 100 years and also because ladder
access to the wall is quite difficult.

The pipes come primed with what is described as grey oxide primer.

I would normally paint them with my favourite 2-part epoxy primer and
then some decent top coat, but maybe there are more standard and easier
paints to apply. Also, should we attempt to paint the inside of the
pipes? The old pipes rusted from the inside. The original "hoppers" at
the top of the pipes are in reasonable condition, presumably because
they were painted inside and out. We are going to re-use them.

Has anyone done this sort of thing and can give any advice or points to
avoid?
--
Bill

You can still buy it. Costs an arm and a leg.

The important thing is to start at the top when installing it.
If there is the slightest pressure in a socket from the pipe above, it
will split it (the socket) open.
You need a good vertical clearance. The joints on vertical pipe
should be open to allow free movement.
They are very heavy and often the fixing allows it to slip down a
little.
You need the special fixings too to get the right appearance/strength.
They are like big nails, ideally leaded in.

On Jul 6, 11:40*am, Bill wrote:
My son's next project is to install two new cast iron drainpipes. The
old ones were rusted through and dangerously detached from the sandstone
wall. It's about a 14 foot straight vertical drop and they take the
rainwater from the roofs in a neighbour's garden.

We think the pipes are original and well over 100 years old and, having
seen the price he has paid, I think we want to do as good a job as
possible so that these last another 100 years and also because ladder
access to the wall is quite difficult.

The pipes come primed with what is described as grey oxide primer.

I would normally paint them with my favourite 2-part epoxy primer and
then some decent top coat, but maybe there are more standard and easier
paints to apply. Also, should we attempt to paint the inside of the
pipes? The old pipes rusted from the inside. The original "hoppers" at
the top of the pipes are in reasonable condition, presumably because
they were painted inside and out. We are going to re-use them.

Has anyone done this sort of thing and can give any advice or points to
avoid?
--
Bill

Oh another thing. You need to make sure they never can get blocked.eg
discharge into a drain that can fill with leaves/debris and block the
pipe
.. If they fill with water and freeze, they split open.