RE: ATM What's Best Material to Create a Tool?

[Bob Prabowo <BOB@bahana.co.id>]

Hi Jim,

> Since different people interchange the word "cement" with the word
> "concrete" I'm not sure what you're saying.  I use cement to refer to
> the bags of powder that go into concrete.  Do you make up a straight
> white cement and water mix or are you talking about a sanded mix or
> one with aggregate in it or what?
> 
What I mean by cement is the stuff that is used to make concrete. You
know, they come in two types, the gray cement and white cement. 
For the tool, I simply mix white cement with water. That's all.

BTW, to increase the strength of the tool ( I read about it somewhere)
some people put a screen (the screen used for window or door screen) in
the mix. Pour the mix on the mirror until it's reached half of the
desired thickness then put a screen on it and then continue pouring the
mix.

For my 13" tool I didn't use screen, but I used three long pieces of
ceramic tile (the same type used on the tool). The tile (which came in
40 cm x 40 cm size) were cut to three 1" x 6" bars. I pour the mix on
the mirror, then I put the tile bars on it (I arrange it so it form an
"H" shape) and then continue pouring the mix. 

I do not know if it really increases the strength of the tool, but at
least it makes me think it's stronger that way.
Hope I don't confuse anyone.

Bob P. Sumitro
Jakarta, Indonesia

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