Greetings everyong. I am writing to provide an update about the progress of development of our very large (1800*1600*1600) 3d printer and the development of the extrusion system so that we can print with our 100% non-toxic bio-composite pellets.
To give a high level summary: The printer arrived from China in February and was assembled inside of a temporary marquee. The first two months of testing were oriented around the filament extruders that came with the printer. Tehrefore I had to extrude my own filament from our bio-composite panels. It took 100 hours of printing to create one pannel. This was because of filament breaking in the filament creation process but also because of breaks during prints. There were also many cloggs in the filament extruder which meant the printing was interrupted while the extruder had to be stripped down, cleaned out and rebuilt. There is more detail about all of this in the www.create.green/journal/may-update
It was decided that a pellet extruder was needed and to remove the entire filament making process. The first pellet extruder that I went with was the Mahor pellet extruder. This extruder had a max nozzle size of 2mm but it had a much higher material output (kg / hour of about 400g / hour). This extruder took a long time to arrive and a long time to callibrate untill I could get the settings right for correct layer adhesion. After two months of failure I finally managed to start to print complete panels for the green camp structures. After printing four panels the extruder would become clogged up very quickly and this meant stripping down the extruder, cleaning it and then rebuilding it. Because of the design of the extruder this was a very fiddly and hard task that meant unwiring the extruder and then re-wiring it again. After completing this 2 hour process it would quickly clog up again. I couldn't complete an entire pannel print without the extruder becoming clogged very quickly. There were also huge problems with the extruder not reaching sufficuent temperature and the printing having a 'heating failure'. I would have to wrap the heating element in huge ammounts of insulation so that it would get to temperature and this made the stripping down and reassembly of the extruder even more laborous and expensive. At this point I couldn't afford more insulation.
I feel it is important to note that the 3D printing company from whom I brought the xyz gantry could have advised me to use a mosfet to more efficiently heat this extruder. I did not realise this at the time.
I then made the decision to change the extruder to the new, prototype Lily Pellet Extruder from a lovely inventor from Panama. After two months this pellet extruder arrived and I spent four weeks begging the Chinese manufacturer of the 3D printer to provide me with a wiring diagram of how the mosfet that comes with the extruder fits into the motherboard and heading system. They provided me with really poor written descriptions and although I provided the with many high quality photo based wiring diagrams that allowed me to determine if new wires needed to be added, or if wires needed to be moved from one position from another (something their descrioptions never clarified) they would send me through the most unclear responses day, after day, after day. It should also be noted that the Chinese 3D printer company from whom I purchased this printer provide ZERO doccumentation for their printer. They send emails with video instructions on how to do certain things. They keep a we-chat group where you can write to their engineers and they will respond if they feel like it. If they do not know the answer to a question they will not say so they will just stay quiet. It can take days to know if they are either just not responding because they can't be bothered or if indeed because they don't know what they are doing.
With the healp of Juan, the engineer behind the Lily Extruder, we were able to troubleshoot the problem installing the mosfet. In the process I determined that the mosfet that came with the extruder was faulty and ordered a new one. In the mean time Juan said that it shouldn't matter and I should test the extruder mounted directly to the motherboard. I did so and the same problem occoured as with the Mahor pellet extruder: the extruder failed to heat up and had a 'heating error' which causes the print to stop. I was then told to change the PID settings (the rate at which the heating catridge heats up) and after doing so found that the printer would heat up but not ever turn off again. It would just keep heating up untill it melted it's self to death. Some days later the Chinese engineers in the we-chat told me that this is because we have the heating chip in the motherboard.
I identified which chip needed to be replaced and ordered a replacement. In trying to re-install the replacement the fixture to the motherboard broke and I needed to take it to an electrical engineer to solder it all back together. After this I installed the new mosfet and the extruder heated up very efficiently and quickly, it was working!!! After about 6 hours of calibration I managed to start to get some good prints. I then started to set up prints for printing the Green Camp System panels with 6mm wall thickness, some with just one layer (with a 3mm nozzle) and some with two layers. The prints were incredibly strong but the external vacuum powered material conveyance system that feeds pellets to the extruder kept beciming clogged and this meant it would just blow down a pipe it had clogged for it's self and no new materials would get to the extruder. The extruder would quickly burn it's self out at it was running hot with no material and as there is no sensor to dedect when the material totally runs out, the printer will just keep printing nothing in thin air. The super hot conditions inside the extruder devoid of material means that I have to strip down the extruder, clear the clogs in the extruder (this is a MUCH less painful process than with the Mahor extruder) and clear the clogs in the pipe of the material conveyance system.
I should say thanks to the Chinese team for editing the G-code of the printer for the Lily Pellet extruder but because they make the code proprietry for their custom MOBO I don't have a choice but to ask for their help.
After all of this resetting I am finding it very hard to find the right layer height to resume printing when I edit the g-code to do so. The extruder comes in about 5-10mm lower than the measurement I made and cut the g-code to. This pushes the part off the print bed and means all that material that has gone into the part is wasted and a new print must start. The last time that this happened I was stripping down the extruder to clean the blocked nozzle and I noticed that no commands on the printer touch screen interface would work. The power button wouldn't even turn off the printer. After turning the printer off at the wall I found that it would not turn on again. Our conclusion is that the fixed heating chip has not had a successful repair of the contact that was broken and this failure has resulted in a failure of the motherboard. I have therefore ordered new motherboard from China that should be here in 15 days!
If this new mother board is stable and works well then I should be able to start printing pannels in about 4-6 hours and that means about two panels a day if I print them individually or if I print them one after another in a row I can print about four a day. At that rate it would take me about a month or two to print all the pannels for one dome. This is clearly far too slow but it does provide a proof of concept for using additive manufacturing for outdoor construction pannels. I could continue to print these pannels and create an elongated egg shaped tunnel into which can construct a refurbished 6 axis robot and onto that mount the very large Massive Dimension 10lb per hour extruder that I have already purchased. Or I could use canvas domes for the structures and just focus on using The Green Manufacture System for printing eco furnature, compost bins, bird-baths, loos, cool sinks, cool tables, cups, bowls, feeding troughs for making friends with the foxes and getting them to hunt the rattys so the birdies can recover from the extinction they now face etc etc
In the mean time I have build my old geodome in the garden and I am renting it out to earn extra income (that allows me to feed myself just about). I have another canvas dome coming to increase the available income as per the eco accomodation business model at the heart of Green Campus. If I buy shorter extrusions for the 3D printer or I modify the low beams inside my garage I will be able to move the 3D printer inside the garage which will then allow me to use the marquee as a yoga / event space. I have a long table available where I can do vegan feasts for the lovely guests that are becoming regulars at this little vegan Green Campus Ellanore (www.create.green/location/ellanore).
This has all been on top of the most challenging personal truoubles of my life involving all the most terrible kinds of family law.
Fingers crossed all that will work out well and this Green Campus will continue to grow and productivity will continue to increase.
The Green Campus Journal chronicles the latest journal entries from all green team members. Look out for the monthly Green News Show for an in-depth update about what's been going on!