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citively charged as they pass through a narrow slot (see figure). The drops then pass through the electrostatic field of a deflection ring, which changes their trajectory based on their charge. In this way the drops are steered either to their correct location on the powder bed or are diverted back into the binder reservoir. This is done in a binary yes or no mode. Keeping the material constantly flowing through the jets prevents clogging which might occur if the flow were actually turned off and on as it is frequently the case with drop-on-demand systems (see selective droplet deposition).

The intricacies of the control parameters and the interdependency of the variables are comparable to those already described for droplet deposition, such as temperature of the liquid binder material, ambient temperature, traveling speed of the placing head, diameter and shape of the orifice, distance of the jets to the part, time of droplet flight29, pressure or feed (flow control), drop-size, drop-frequency, the exit velocity at the orifice and the deceleration of the drop in air, the viscosity of the binding material, the packing density (percentage of void) and the actual shape of the powder material, mechanical forces applied during powder spreading and powder densification from vibration etc. etc.