Lets make a threadstruder!

I see that someone has made a carbon fiber thread printer. It seems to lay down pre resin soaked thread with one “nozzle” and then print plastic over it. But it doesn’t seem to be open source. So, I wanna make one. I have a spool of 0.010 mm carbon fiber thread on the way, but I’m not sure of the best approach to actually make the thread impregnation piece. My initial idea is to drill a small 0.011mm hole into the side of a .5 (or maybe even a .75mm) nozzle and thread the carbon fiber into it with the filliament retracted. then extrude and hope the force of the plastic is enough to grab the thread and encapsulate it. . I’m worried that it would only work in the direction printing towards the hole, and would lead to the thread being on top of the molten plastic extrusion in directions away from the side with the hole.

My other, less workable idea is to try and feed the carbon thread in from the top with the filliament and hope the flow of molten plastic pulls it down and out. I think it would work if I can get it started in the first place, but I have no idea how the heck i would thread the carbon into the cold nozzle the first time short of tying it off to a piece of filliament and hopeing it eventually came out the other end without tangling in the melt chamber.

The last Idea I came up with seems like it would be technically infeasable. I’m thinking some sort of dual ring extruder, like what they use to extrude PVC pipe, and another hole down the middle for the thread itself. filliament would feed down one channel, thrad next to it, and through it in the melt chamber, filliament would come out the middle and plastic would extrude around it. I can see a workable model for that in my brain, but i have no idea how to even begin thinking about milling something that intricate on that small a scale.

Any ideas? I’m willing to give a shot to building one if we can come up with something viable. Would be nice to make something that could be used on a Taz as well.

I had toyed around with similar idea for a different application. The difficulty I see are that the thread would have to be fed at the rate of extrusion which would be faster than the filament feeding in. (Unless you could implant the the thread into the resin filament spiraled in a manner that would be correct for feeding… tricky). Yet once you got it started the filament impregnated should help pull the rest along.I would think the approach would be to have them merge as close to nozzle as possible. But I think you would need some active cooling to make the bridge as short as possible. Maybe something like the attached sketch? :bulb:

That’s definitely along the same lines as what I was picturing in my head. The biggest hurdle would be making sure the thread didn’t destroy your starting layer. Then again, it’s a specialized enough task that I could almost see printing onto “starter pucks” of compatible plastic locked into a heated vice being a viable option. if you are reinforcing something with carbon fiber, chances are it isn’t going to be spindly, and it will have a solid mounting point somewhere on it.

I got the carbon fiber “thread” which turned out to be huuuuge carbon fiber yarn. I think I can separate out individual usable strands from it though which should allow for at least a decent test.

Couldn’t you just run a skirt to get it started and serve as an anchor and then run it to the actual print? Once it is done the just cut the starting connection.