How can I recognize that the clay is ready to be used for 3D printing?

Depending on the type of material you want to use, the goal is to reach a mixture that is fluid enough to be able to come out from the small nozzles but at the same time hard enough to avoid collapse during printing.
It is therefore a matter of adding or removing water from the dough.
To determine when the material has the right characteristics for printing, just use the syringe supplied with the printer or the WASP Clay Kit.

Then:
Put the material inside the syringe. (any normal 5 ml syringe is good for this use – just cut the edge)
Push the piston up to 1 ml notch – You can have three different options:

1. the material is horizontal. this dough is too hard 
   

   

    

2. The material immediately collapses down. This dough is too soft 
   

   

    

3. The material slightly collapses down. This dough is correct 
   

   

    

A further test is to verify that , once the dough in under pressure inside the tank – when coming out,  the correct pressure must be between 4 and 5 bar.