Powder application apparatus and method of operating a powder application apparatus

A method of manufacturing work pieces by exposing powder layers to electromagnetic radiation or particle radiation, the method comprising:

• providing a housing;
• providing a carrier below the housing;
• and
• providing a first stopper mounted to a sidewall of the housing;
• providing a powder application apparatus comprising:
• a first powder storage provided in a first part of the powder application apparatus to receive and store raw material powder,
• a first powder supply channel provided in a second part of the powder application apparatus to discharge raw material powder from the first powder storage onto the carrier located below the powder application apparatus, and
• a first channel opening/closing element having a first end and an opening, and slidably disposed in the second part of the powder application apparatus to move between a first position where the opening aligns with the first powder supply channel to allow the discharge of raw material powder from the first powder storage onto the carrier, and a second position where the opening is not aligned with the first powder supply channel to prevent the discharge of raw material powder from the first powder storage onto the carrier;
• moving the powder application apparatus over the carrier towards the first stopper;
• abutting the first end of the first channel opening/closing element against the first stopper to move the first channel opening/closing element from the second position to the first position,
• wherein the first channel opening/closing element is moved between the first position and the second position by means of an external mechanical force acting on the first channel opening/closing element, the external mechanical force being caused by abutting the first channel opening/closing element against the first stopper when moving the powder application apparatus over the carrier.