how do you make dustless white school chalk from plaster of paris?

Question

how do you make dustless white school chalk from plaster of paris?

Answer 1

these places say you can't.

http://www.gypsumsolutions.com/webQA/webQA.asp?category=All

. To Eldon Guru, I have experimented with gypsum power to make dustless chalk and failed but as i have read the questions and answers i realise that is is not possible. What i would like to know than is what are the raw material to make dustless chalk.

Hi, Dustless chalk is made from a mixture of materials such as whiting, a special lime and binders. We don't make any of the ingredients and thus only have a general knowledge about the mixture which could vary from maker to maker.



39. I would like to know the feasibility of dustless chalk production through the use of gypsum.

It would be very difficult to make dustless chalk using plaster. Making the chalk stick dense reduces the dust but makes writing more difficult and tends to produce the blackboard screech. Dustless chalk is made from other raw materials.

http://www.trainweb.org/oldtimetrains/chalkmaking.htm

There are two ways of making chalk; in one the chalk is molded, in the other it is pressed and extruded, like toothpaste from a tube. Extruded chalk, whether white or specifically coloured, is

most commonly used on chalkboards in school, as it tends to be dense and "dustless".



To produce extrued chalk, the makers first stir together, by machine, several white powders which look like flour. The most important of these is calcium carbonate and water-washed clay. If the chalk is to be coloured,

Answer 2

No. The chalk does not have a binder in it and if you add water as with plaster of paris you will just get wet chalk. Most plasters are calcium sulfate hemihydrate, while sidewalk chalk is mostly just calcium. If you are looking for coloured plaster you can grind up chalk and add it to the plaster to colour it. Anthony pittarelli

Answer 3

Dustless School chalk can be produced from a Mixture of POP and Calcium Carbornate plus water. The POP/Calcium Mixture proportion is vital to making the chalk smooth and dustless.I learnt the step by step of dustless school chalk production here http://www.homebusinessmanuals.com/2012/07/how-to-make-school-chalk-at-home-and.html

Answer 4

pop and calcium carbonate produces semi dustless chalk ,the chalk is poor in strength ,very light compared to dustless chalk probably because its molecules are not dense enough . addition of a filler like kaolin improves the mass a little ,while use of a binder cmc ,affects the setting completely , the pop looses that ability.