Cob: Counter-attacks

[ToSwink]

Not sure if I understand thread sorry if wrong.
When I took masonry classes we made park benchs which when finsihed were
smooth.
We took sand/creek pebbles and dropped them on top of cement.
Then when it was dry we took what was called a holy stone.
As we ran water over surface we rubbed the stone untill the surface was
smooth.
Same thing should occur on any cement surface.
----- Original Message -----
From: "Frances Grill" <grill at vtc.net>
To: <coblist at deatech.com>
Sent: Friday, November 09, 2001 5:10 PM
Subject: Re: Re:Cob: Counter-attacks


>
>     Greetings, Boy Charmaine, you never cease to amaze me! I'd have to
> quit ranching to read as much as you do. This inverted counter-attack
> does leave me with a few questions, Troweling has several purposes as
> you well know. Obviously it serves to flatten the exposed surface. It
> also serves to draw cement and water up through the aggregate so that
> all the interior surfaces and spaces get covered with bonding agent
> (cement in most cases). Stone or aggregate gets pushed down and cement
> comes to the surface to form a sort of monolithic plane.As the concrete
> sets, each pass with the finish trowel "burns" the surface to proper
> glass like hardness...burnishes the surface just as a rub on clay
> plaster would. So with none of this happening on the underside, how does
> one get a smooth non-porous surface? Even micro pores are going to store
> bacteria no???What am i missing, Besides a copy od Fine Home Building ?
>  PAZ,Pedro
>
>