Okay i put together a second experimental batch of my White Matter© today. At this point it is some two hours and seventeen minutes in and it is working just as the first batch did as in it is not going off (hard) in the mixing bowl. I 'definately' have cracked the secret of retarding the plaster of Paris going off too quickly. However, i made some slight changes to the tissue paper content this time to see what would happen.
In the first batch i made the mix was approximately forty percent tissue paper to sixty percent plaster of Paris plus ingredient 'x' which i will reveal later when i know i have perfect results every time. Now as i have said it is staying wet and completely useable as the first batch did, however drying times in the moulds has increased dramatically and in some moulds there is serious shrinkage. Water is pooling in the lower hollow regions in the moulds too.
I have been aiming at getting the mix to a fifty percent tissue pulp and fifty percent plaster. This it appears will simply not work. Not with as fast in the mould drying times anyway. The shrinkage i 'think' is due to the 'increase' of water which is being introduced along with the increased tissue pulp levels 'not' the tissue itself. Now don't take my word on that yet. I am still only working from personal theories here and they are best sketchy at this point. I am still working out the reasons 'why' this mix works as it does. Plaster after all 'will' go off no matter how much water you add. It will take longer of course but it 'will' none the less seprate from the eccess water sink and go off under the water. This consistant reaction is how you clean your containers after use after all.
To clean mixing containers you want to reuse simply add water to the container you were using. Use a paint brush, cloth or sponge to wipe down the sides of the container with the water in the container. Then simply place the container somewhere it will not be disturbed for a day or two. Later go back to it to find most of the water has evaporated leaving a solid block of plaster at the bottom of the container. If you have no use for this plaster simply dispose of it as your local waste management authorities advise. Or you can break it down with a hammer, oven bake it dry. Run it through a coffee grinder etc, voila re-useable plaster again.
When it comes to using the new batch on existing plaster/White Matter© objects IE: previously made skulls there is 'no' change to the way the mix reacts as with the first batch. In this respect the results are identical. In fact i am currently using it to join up the halves of the plaster skulls i made yesterday. Not only are the two halves bonding beautifully, seamlessly. The new batch of White Matter© is acting exactly as the first experimental batch did in this instance.
I still have another twelve skull halves to build up today which is going to take me up to my time to quit for the day. I will make a third and i am sure final experimental batch tomorrow with a reduced tissue paper content matcing the first batch which should fix the increased drying times and shrinkage issues i created with toady's experimental batch.
So to round off for today not total perfect results but i did throw a spanner in the works by increasing the paper content. Then again this is all part and parcel of experimenting is it not lol.