System and method for manufacturing a part

1. A manufacturing system comprising:

a substrate;

a support structure; and

a first powder container to hold a first powder having first particles;

a print head having a first inner nozzle for directing the first powder from the at least one powder hopper onto the substrate, the first inner nozzle having a lower surface that is sufficiently near the substrate for powder to flow out of the first inner nozzle and stop flowing out of the first inner nozzle when there is no more room below the first inner nozzle, and a first outer nozzle, the first outer nozzle positioned around the first inner nozzle, wherein the first inner nozzle is mounted to the first powder container for vertical movement between a first position and a second position;

a print head actuator;

a computer that is programmable to cause movement of the print head actuator for the print head actuator to move the print head relative to the support structure, causing the first powder to resume flow out of the first inner nozzle;

a first inner nozzle actuator;

a first connecting piece having a lower portion secured to the first inner nozzle and an upper portion located higher than the upper end of the first inner nozzle, the first inner nozzle actuator being attached to the upper portion of the first connecting piece, wherein the computer is programmable to cause movement of the first inner nozzle actuator, causing movement of the first inner nozzle and first outer nozzle relative to one another between the first position wherein the first powder flowing through the first inner nozzle does not reach the first outer nozzle and the second position wherein the first powder flowing through the first inner nozzle flows laterally and does reach the first outer nozzle and powder stops flowing out of the first outer nozzle when there is no more room below the first outer nozzle and wherein said movement of the print head relative to the support structure caused the first powder to resume flow out of the first outer nozzle; and

a connection scheme which, when employed, connects the first particles to one another to form a part.

2. The system of claim 1 , wherein center lines of the first inner nozzle and first outer nozzle are concentric.

3. The system of claim 1 , wherein a center line of the first inner nozzle is offset relative to a center line of the first outer nozzle.

4. The system of claim 1 , wherein the first connecting piece and the first inner nozzle are made out of a common piece of material to form a valve piece.

5. The system of claim 1 , further comprising:

a print head frame, the first inner nozzle actuator having a portion connected to the print head frame to move the first inner nozzle relative to the print head frame.

6. The system of claim 1 , further comprising:

a print head frame, the first inner nozzle actuator being connected through the print head frame to the first inner nozzle and having a portion connected to the first powder container to move the first powder container relative to the first inner nozzle.