On Sat, 12 Aug 2006 11:36:43 -0700, Weatherlawyer wrote:

John Stumbles wrote:

Well if God can be created out of nothing, why not?

What makes you think that he did?

That he did what?

The bible says he "hung it upon nothing" and that he "created it not
for nothing". I don't remember a quote from that source implying he
made it "out of nothing".

From my limited recollection of that 'source' it is silent on the
question of where God came from.

Notwithstanding wild guesses about cosmogeny, I was actually asking you
where the oil came from. Not that I don't already know. I was just
wondering how circular your reasoning could get around to.

Just supposing I did believe that fossil fuels came from the tooth
fairy, easter bunny, Father Xmas or God, how would that be a
case of circular reasoning?
http://en.wikipedia.org/wiki/Circular_reasoning

Not that I don't already know, of course.

Of course.

The message
from Stuart Noble contains these words:

Maybe you could spray it with soda water to accelerate the initial set.

Joke not - It has been done! It works fine but the clients start
lookig suspicious

How about dry ice?

Supercritical CO2 has been used for hardening concrete. It's expensive,
so guess who gets to use it? Yup, the military!

--
Skipweasel
Pay no attention to that man behind the curtain.

Weatherlawyer wrote:
wrote:

Where can we read more about types of cement? IIRC theres opc, hac,
sulphate resisting, weld cement, no doubt more too.

reservoir of informatoin snipped

Thanks, and I'll check out lafarge when I get time.

NT

wrote:
IME, if you can't protect ordinary lime mortar from the weather, shallow
applications such as pointing will be washed away by the first rainfall.
Hanging damp sacks all over the place doesn't seem that practical to me.

Do you mean heavy rain washing out new pointing? The initial set of at
least the surface should take a few hours. After that I would be
surprised if it washed out to a significant degree with normal
rainfall. I have heard at (at a limes seminar) of a heavy section of
new/repair lathe and plaster ceiling detaching - as a consequence of
poor mix and poor application. Potentially quite dangerous - it does
take time (weeks/months) for a thick area of lime mortar/plaster to
carbonate right through and gain it's full strength.

The other issue is the degree to which modern additives have improved
the properties of cement. At a basic level I'm sure we're all familiar
with how pva reduces cracking and doubtless there are more sophisticated
products around.

I don't think you can get away from the fact that cement pointing will
trap moisture and lead to soft bricks spalling. It also acts as a
sacraficial material around limestone, so it's the mortar that slowly
erodes and not the stones.


My impression is that lime pointing does it worse actually.

Old bricks are soft and porous and crumbly, they need a soft crumbly
porous mortar like lime. Modern bricks are not like that.