New methods and systems for manufacturing a three-dimensional form, comprising steps of providing a plurality of particulates; contacting the particulates with an activation agent; contacting particulates having the activation agent with a binder material that is activatable by the activation agent; at least partially hardening the binder for forming a layer of the three-dimensional form; and repeating these steps to form the remainder of the three-dimensional form. Following sequential application of all required layers and binder material to make the form, the unbound particles are appropriately removed (and optionally re-used), to result in the desired three-dimensional form. The invention also contemplates a novel method for preparing a form, where unbound particulates free of binder material are re-claimed.