Using electroplating we have coated a section of a 3D print in copper.
To do this we cleaned up a scrap piece of copper pipe with wire wool. The tube was connected up to the positive side of the power supply and was submerged it in copper sulphate solution. This then became the anode.
The 3D print was created in PLA (insulator) and F-Electric PLA (conductor) on our dual-head Ormerod. The print was created with holes to attach wires to the conducting filament. We needed fat multi-strand wire to make good contact, so we used speaker cable.
This wire was then connected to the negative side of the power supply making the printed F-Electric the cathode and the 3D print was submerged in the CuSO4 solution (with a bit of extra H2SO4). The power was then applied.
Initially the wire connecting to the 3D print were submerged in the copper sulphate solution. The wires being copper had very high conductivity, so most of the current was going into the solution via them. So a large amount of copper was being deposited around the wires rather than on the conducting part of the 3D print.
The experiment was paused and the excess copper was knocked off the connecting wire. Two new wires were then connected to the F-Electric part of the print and kept above the solution when the 3D print was returned to the solution. Copper then started to build up around the F-Electric PLA.
After about 5 hours the copper pipe had disintegrated so we switched off the power and removed everything from the solution.
The end results:
The F-Electric has very good low resistivity for an electrically-conducting polymer. But the effects of its resistance can be seen in the uneven distribution of the coating. One approach may be to reduce the concentration of the copper sulphate solution to raise its resistance. The two should then be better matched, leading to a more uniform coating. It will be slower, of course, but this isn’t time critical.
After that we will try an alternative. We will dissolve some F-Electric in DiChloroMethane (good ventilation needed) and paint it on a 3D-printed part to see if we can copper-plate the entire surface. This is the equivalent of painting glue on a part then covering it in graphite, which others have done. If this works, we will try using the F-Electric just for the outer layer of the print, with ordinary PLA inside.
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