Why can't we have FDM printers print in Metal Filament?

[WildZBill]

A novel idea that I have considered is suspending metal particles in a fluid, flowing the fluid through a nozzle with an electrical charge at the tip that would cause the metal to be attracted to the work. Of course you would constantly recycle the working fluid.

[3dkarma]

I'm aware of two ways to 3d-print in metal that are fairly close to FDM.

The first uses a two stage process. First stage is to print a clay made up almost but not entirely of metal particles. You use a paste extruder, such as this one from thingiverse, loaded with a metallic clay such as this (which evidently sees a lot of use by jewelry makers). Second stage is to fire the piece in a kiln. You end up with a metal piece.

The second uses an arc welder as the hot end of the extruder. Welding wire is fed to the business end the same way it's done in a normal arc welder. Lots of current is pumped through and hey-presto: 3d welded metal. Article here.

[Markum_Debreeze]

A novel idea that I have considered is suspending metal particles in a fluid, flowing the fluid through a nozzle with an electrical charge at the tip that would cause the metal to be attracted to the work. Of course you would constantly recycle the working fluid.

Bill, I'd love to see if this could work. In theory it would, but would there be a mess involved? Please try it. I beg you to

[Feign]

A novel idea that I have considered is suspending metal particles in a fluid, flowing the fluid through a nozzle with an electrical charge at the tip that would cause the metal to be attracted to the work. Of course you would constantly recycle the working fluid.

Sort of like a directed electroplating process, but with a flowing fluid rather than a suspension? There would be very little way to control where the metal plates at the fluid runoff from the point of intended deposition... Actually, I seem to remember a kind of vapor deposition additive manufacturing that blasts a charged work surface with charged metal particles. I thought it had lots of potential, but never saw a followup of it since the initial report.

Of course, just using an automated MIG welder setup like 3D Karma mentioned.

[LambdaFF]

Sort of like a directed electroplating process, but with a flowing fluid rather than a suspension? There would be very little way to control where the metal plates at the fluid runoff from the point of intended deposition... Actually, I seem to remember a kind of vapor deposition additive manufacturing that blasts a charged work surface with charged metal particles. I thought it had lots of potential, but never saw a followup of it since the initial report.

Of course, just using an automated MIG welder setup like 3D Karma mentioned.

I think it has been developped to repair helicopter magnesium gear boxes in australia.