> The alpha version of the SpoolHead is being
Cool. I watched a few of your videos and looked at some images, but couldn't get a feel for the scale at which you are printing.
Would you mind posting an image with your 'spiral' device next to a fixed measure - a ruler or hold it in a hand or something?
How easily do you forsee being able to print multiple layers, using fine motor grade wire? I suspect a printable simple solinoid based device or motor can't be too far off, using the techniques you have forged in your research. I suspect that kind of device would be easier to print than actual wiring for electronics?
I think printing multiple layers with fine wire is feasible. The hardest part is software really. There's one other technique I'd like to investigate, which is printing the wire continuously along Z - that would make printing embedded coils easier for sure, but it would take some extra mechanics.
But to print any useful electromechanical device, we're missing one other ingredient - an iron core to conduct flux. Otherwise solenoids, motors, etc will be extremely weak and inefficient. The best way to do this, in my opinion, would be to print using a 3mm PLA filament that's also chock-full of iron powder. Ideally it would be about 90% iron, 10% PLA, by weight, or maybe even more. That might be brittle and thus tricky to extrude; it would take some testing. But using it we could print magnetic circuits.
Nice Image. I was hoping it would be a little smaller, but we have to start somewhere, and the research area great, IMHO.
> But to print any useful electromechanical device, we're missing one other ingredient - an iron core to conduct flux.
Indeed. Air core is fine for RF frequencies, but would not induce much constant magnetic force for something electromechanical applications. Lots of ideas to test here, too.. In addition to using iron powder (either extruded, or added in a hardening paste/epoxy post process..), using a second or dual print head filled with fine steel wire could also yield interesting results.
Fantastic progress Jacob! I have been wondering how to snip the fiberglass strands at the end of a fiberglass, or combined fiberglass in plastic extruder. How are you doing the cutting here? I see a solenoid, but it is not down at the tip. It looks like you would have to cut the wire a little in advance of when you place the last of it in the plastic. You would need software that checked for when you were getting close but not yet quite at the end of a wire to send the snip signal, then either push the last of the wire out, or drag the extruder tip away and have the already secured parts of the wire pull out the last bit and press it into the hot plastic.
Also how are you embedding the wire in the plastic? Do you heat the plastic first and then push the wire into it? Do you heat the wire as it comes out and then push the hot wire into the plastic? Or do you extrude hot plastic at the same time to surround or bury it? Regardless, great work!
... yesterday i remembered some of the talk in the Wiki and thought more concrete about 'lasersupported placing' ...
Here you push a really short piece of thin plastic fiber (maybe 0.1mm thick) from a spool in the focus of a diodelaser touching the surface of the build base.
When heating the tip of the fiber with the laser, it melts to a blob, wetting the surface, but still connected to the cold fiber too.
Now - either you lever the head with the fiber, so it rips apart from the blob and the heating energy from the laser should remelt the thin connecting string so it separates instantly and vanishes in the resting blob and the retracted fibertip ... or you move the head a step in the direction of continuous fabbing a thread, premelt the surface, push the next piece of fiber in the molten focus (or feed it synchronous with your move if the wire is thin enough to melt completely) and melt the next blob, still fused with the previous.
So you'll have a sort of 'shape-deposition', where you fab with continuous lines of molten blobs resembling a track of fused material, similar to the normal extruding process.
You have to rotate the head in the fabbing direction, so it's something more complicated than 'simply fabbing a line' - but you can use any diameter of fibers (even 0.01mm thick wires will work with a 0.1mm laser-spot!), different materials (plastic, metal, glass, ceramics, ...) and the separating with laser-heating will avoid strings and you can place single blobs in the size of the fiber diameter ...
> Fantastic progress Jacob! I have been wondering
> how to snip the fiberglass strands at the end of a
> fiberglass, or combined fiberglass in plastic
> extruder. How are you doing the cutting here? I
> see a solenoid, but it is not down at the tip. It
> looks like you would have to cut the wire a little
> in advance of when you place the last of it in the
> plastic. You would need software that checked for
> when you were getting close but not yet quite at
> the end of a wire to send the snip signal, then
> either push the last of the wire out, or drag the
> extruder tip away and have the already secured
> parts of the wire pull out the last bit and press
> it into the hot plastic.
> Also how are you embedding the wire in the
> plastic? Do you heat the plastic first and then
> push the wire into it? Do you heat the wire as it
> comes out and then push the hot wire into the
> plastic? Or do you extrude hot plastic at the same
> time to surround or bury it? Regardless, great
Thanks! I'm glad you approve. We found that heating the wire itself was sufficient. Then it just pushed very easily into the plastic. When it cooled, the plastic gripped the wire with incredible strength!
The solenoid cutter turned out to be ineffective, and we ran out of time to experiment with different options. However, Dany Lipsker found that the best method to cut wires was an electrically-driven pair of hair trimmer scissors, if I recall correctly. That would be a good method to try out. Yes, once it's been cut we just have to rely on the attached plastic pulling the remaining wire out.
This project is on hold for now while we build a faster, higher-precision printer... probably we'll return to it when we get back to pursuing the Gada prize. I have some ideas for miniaturization.
That's been some really nice work! I'd like to ask a question though - why is everybody so narrowly focused on using metal wire printing to print out circuits? What about using it to print out structural metal parts? I would think that would be of much greater utility early on, as compared to printing circuits.
My suggestion is to take your fabulous work and apply it towards printing of small metal parts. How about printing custom rings or jewelry for people to wear?