(Preview of FUTURE project) Plastic-Extruding, Filament-making Machine
This will be a (near) future project. I plan to finish the 3D printer before I worry about completing this plastic filament making machine, but I have a good start on it already.
I bought the auger bit that I will need to carry the plastic pellets to the hot-end to extrude filament (which I can then use in my 3D printer). I took the pieces over to my brother's house to show him and without having to ask him, he took the pieces of pipe out to his shop and cut the slot that I will need in the pipe where the plastic bits will drop in and get caught by the screw.
Having only a lathe and not a full milling machine, I had planned to just cut a slot in the pipe by using my grinding wheel and trying to clean it up with the Dremel hand-tool. He did save me a lot of work by putting it on his Milling machine and cutting the slot for me.
☺ Thanks, Ric !
In the 3D printer, it is extruding a much finer line to hopefully add better detail to extruded pieces. In this machine, I will be extruding a 3mm diameter strand, so a bit more plastic should be heating at a time. Since I will want this plastic blob to heat up nicely, I have a larger chamber to heat. Earlier I used a copper welding tip and an aluminum block, but since brass fittings are available to thread onto steel pipe, I will use brass this time.
I've purchased a brass coupling and a brass end plug. These will be heated, probably with the same resistor method used before, although with a larger volume of metal and plastic to heat, it will take more than just the 2 resistors that worked before. You can also get band heaters, but I think they are more expensive. I will check that out later.
Now with the auger screw turning in the direction to push the plastic towards the extruder end, the action-reaction principle tells me there is be equal pressure trying to push the screw backward, out the other end. In my basement workshop (metal shop) I found a perfect cap for that end of the steel pipe. It is actually a collar ring that was previously in one of the bathrooms, holding the feed pipe to the faucet, (prior to changing to a different faucet which had a different size pipes). This ring is the perfect size to screw onto the pipe and have a hole through which the shank of the auger screw fits. That will keep the auger in the pipe where it should be to push the plastic through.
So now I have most of the pipe hardware I will need for this filament extruding machine, but there is still the electronics and the drive.
I still need a drive mechanism to connect the screw shaft to the motor. This may either be in the form of belt and pulleys, chain and sprockets, or straight gears. A belt and pulleys may be the easiest to locate or fabricate. (And to think I threw out a couple old bicycles that I could have taken the chain and sprockets from...!) As to gears, I have never made nor purchased a rotary table with which I can make gears, so that idea is pretty much out the window, unless I were to find some on ebay that are reasonably priced. I will decide on how to drive the screw later when I figure out what is readily available.
As I mention above, this project is only just started, and will not be finished until later.