The weight of your final product will be the weight of the paper plus the weight of additives like portland cement, borax, sand, etc. A bit of the water stays after hydrating the cement and as moisture content in the pc.
When you mix with a lot of water the excess water just runs out of your forms, leaving about the same density as pc mixed with less water. For ease of mixing and pumping I normally mix with quite a bit of water. The paper pulps better/easier with more water. When I can, I try to capture the runoff for reuse, but in many cases that just isn't practical. Luckily most of the cement and additives are filtered by the fibers and stay behind when the water drains. The amount of water is not critical since most of it leaves rapidly, the ratio of paper/cement/additives is what determines your density.
You can compress after mixing. As Judith said, you can add more cement, sand, gravel. Strength is not normally a problem since pc is ALWAYS used under compression, never under tension. In general pc is used in thick walls, and this gives plenty of compressive strength, especially when the weight is spread with a bond beam. Tests have shown "normal" pc to have in the range of 400psi compression strength, depending on the exact mix used.
If you haven't yet mixed any pulp, try a small batch in a cheap blender. Dump it into a form with openings in the bottom and let it drain. Do another and compress it. Experiment a little with cement and sand.
spaceman
On 1/5/2012 1:31 PM, Ales Patera wrote:
Hi I just want to ask if I understand it right how to make desired mount of papercrete with density I want For example if I want 1 m3 (35 cu ft) of pc with density 650 kg/m3 (40.5 lb/ft3) I'll take 1m3 of water and put into it 650kg of ingredients - dry weight (like 470kg of paper, 120kg of cement and 60kg lime) And if I want pc with density for example 350 kg/m3 I just put less ingredients into same amount of water, maybe with little recipe adjustment. Is my idea of it right? So the density of a final product is controlled by density of paper slurry I'll make and then add other ingredients by weight ratio of dry paper. ------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/papercreters/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/papercreters/join (Yahoo! ID required) <*> To change settings via email: papercreters-digest@yahoogroups.com papercreters-fullfeatured@yahoogroups.com <*> To unsubscribe from this group, send an email to: papercreters-unsubscribe@yahoogroups.com <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/ ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.1901 / Virus Database: 2109/4728 - Release Date: 01/07/12
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