Cold spray powder feeders with in-situ powder blending

A method of providing blended powder for use in a mobile cold spray system, comprising:

• providing a powder feeder having a rotatable drum body, wherein the rotatable drum body has a circumferential wall with an opening on a first end and a plurality of metering apertures on an opposed second end;
• providing a drum guide with a rotation surface that slidably contacts and supports an outer surface of the drum body during rotation of the drum body, the drum guide having an outlet chamber fluidly coupled to an outlet tube of the powder feeder;
• providing a drum rider that contacts an interior surface of the rotatable drum body and wherein the drum rider is fixed with respect to the drum body as it rotates, the drum rider having an internal blow down chamber fluidly coupled to a carrier gas tube of the powder feeder;
• providing a housing that surrounds the drum body;
• and
• providing a support structure that is coupled to the housing, wherein the support structure is configured and adapted for supporting the housing such that the drum body rotates about a rotation axis for blending powder disposed therein, wherein a surface of the drum rider wipes an interior surface of the rotatable drum body in order to fill the plurality of metering apertures with the powder and wherein each of the plurality of metering apertures are sequentially aligned with the outlet chamber and the internal blow down chamber such that powder in each of the plurality of metering apertures is provided to the outlet tube of the powder feeder.