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Hello everybody,
Just a little message for say that i have perhaps found a latex for the first varnish.
An enterprise in France seem ready to sell me latex ADS (air dried sheet). This latex is unsmoke. They tell me the answer tomorrow. I cross all my fingers .
If it's good i will start the first varnish soon....cross all your fingers with me.
Shaz
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*fingers crossed*
You're doing awesome work... keep it up!
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Thank you holmburgers,
Cross all your fingers for me for tomorrow. 
Shaz
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Hello everybody,
You know what ! I'm happy. I'm gone buy it the 27...of this month .
I will put some photos. It cost 30 euros for 3 kilos. It's not expensive.
Shaz
Last edited by shaz; 03-10-2011 at 04:22 AM. Click to view previous post history.
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I found this on internet but i don't understand all :
Crepes
Pale crepe rubber is among the highest quality crepes. Coagulation of this high-quality natural rubber is achieved with sodium hydrogen sulfite (NaHSO3). The clean coagulum is washed and milled. This produces sheets between 1.2 and 1.5 mm thick and 24 cm wide. The washing process removes from the coagulum considerable amounts of the serum constituents which can cause rotting. The sheets are dried in drying rooms for 2.5 to 4 days at 37°C or air-dried for 5 to 10 days on drying floors.
Excessive temperatures lead to discolored patches in the sheets as a result of oxidation. The sheets are packed as bales and marketed as "thin pale crepe".
The 10-mm crepe from Sri Lanka is marketed as "thick pale crepe".
Sheets
Two different types of sheets are distinguished:
ADS (air dried sheets)
Air dried sheets are less common. They have an appearance similar to RSS (ribbed smoked sheets), but are more transparent, as they are manufactured in smoke-free rooms.
RSS (ribbed smoked sheets) (see Figure 1)
The fresh latex is diluted to a rubber content of 15 - 16% and coagulated in coagulation tanks using formic acid or acetic acid. Lumps of coagulum are formed after the acid has acted for 3-4 hours. After milling and washing, sheets between 2.5 and 3.5 mm thick, 24 cm wide and 90 or 135 cm in length are produced. The final mill is an embossed mill, which gives the sheets their ribbed structure. Since these rubber sheets are not washed as intensively as crepes, they contain a higher proportion of serum constituents which encourage mold and rotting. For this reason, the sheets undergo an additional preservation process in which they are smoked in smokehouses. The sheets are hung in the smokehouses and dried for a week at temperatures up to 60°C. The smoke resulting from burning Hevea (rubber tree) wood and other organic materials such as coconut husks preserves the sheets. The specific smell of these sheets is caused by the materials used to produce the smoke. The sheets are pressed into bales and wrapped in protective sheets. The surface is protected from oxidation by application of a bale coating solution and talcum.
Can you tell me if there is a big différence between the two rubber.
If there is a big difference i must keep on searching and forget the ADS latex
Thank you in advance.
Shaz
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I tried to translate and i think that there is a big difference....they speak about "rotting" for the ADS...
I have to keep on searching for Pale latex crepe. .
Shaz
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 Originally Posted by shaz
I found this on internet but i don't understand all...
Where did you find this? How old is it?
I don't understand it either, but basically it explains two modes of rubber production(?). This is all very fascinating, but I'm having troubling understanding where it fits into the autochrome.
Ok... here's what I found to give some background for those as clueless as me...
Smoked rubber: a type of crude natural rubber in the form of brown sheets obtained by coagulating latex with an acid, rolling it into sheets, and drying over open wood fires. It is the main raw material for natural rubber products Also called ribbed and smoked sheet. Compare crepe rubber
Crepe rubber: a type of crude natural rubber in the form of colourless or pale yellow crinkled sheets, prepared by pressing bleached coagulated latex through corrugated rollers: used for the soles of shoes and in making certain surgical and medical goods Sometimes shortened to crepe. Compare smoked rubber
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I think that trying to recreate the Autochrome step by step, material by material, will only result in many of these -------> 
I suggest that you become OK with the idea of using alternative materials, because truth-be-told, the Lumiere's picked the best materials that they had access to and so should you.
Best luck, chin up!
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