After receiving my hotly anticipated Filastruder kit, I couldn’t wait to put it together. Starting with the mechanical build, completed over the course of a few afternoons, things seemed to be going smoothly. I had ordered the enclosure kit to go along with the Filastruder, and after a slight hickup with the interior fit of the upgraded v1.6 motor that Filastruder creator Tim Elmore helped me sort out quickly and efficiently via email, my small-scale home extruder was ready to be imbued with electronic life.
This was the part I had been nervous about from the beginning, and even more so as I read the sparse instructions included with the kit. While I have accumulated some experience with soldering PCB assemblies over the last year, and my Arduino skills are improving all the time, doing wiring on a much larger scale is not something I am totally comfortable with yet. I think mostly I struggled with visualising what the end product was supposed to look like – how the wires are held together (soldering or crimping?), how long the wires are supposed to be, how everything fits in the case with the motor. I found very little on this subject on the Solidoodle Forum, the first point of call for any Filastruder owner, and what I did find looked positively lethal and not something I would want to run unattended in my studio. I read on the forum that the extrusion process takes between 8-12 hours or even longer, depending on how much material you are extruding, and I felt that I needed to be completely comfortable with running the extruder for that length of time without worrying about electrical fires. So what to do?
The first clue I found when I finally had the time to get stuck into the electronics assembly were a few large crimp connectors that had been included to wire up the various switches. If you have been following my blog you will know that I have recently developed a bit of a thing for electronics crimping – albeit on a much smaller scale. Crimps are a great and very reliable way to form an electrical connection, and my interest in the huge variety of colourful larger crimp connectors had been stirred already during a previous visit to Maplin. Learning from my previous forays into crimping, I decided to make another trip to pick up some more connectors as well as the appropriate crimping pliers. If you are going to get involved with crimping larger style connectors, a pair of ratcheted pliers is absolutely essential – and not the right place to skimp; your wrists will thank you for using a decent pair that exerts enough pressure to form a secure connection the first time round. Armed with my new tools and an excellent YouTube tutorial on electrical crimping, I decided to tackle the switch connectors first:
After a few unsuccessful attempts and failed connections, the results of my crimping efforts were starting to improve and the wiring was beginning to take shape. The Sestos controller has screw terminals, so I attached ring terminal crimps on the ends of the wires to create a better connection than I would have by just simply attaching the bare wires. After a few more hours and some wasted crimps, this is what I ended up with:
The thermocouple posed another challenge – its two large prongs did not fit well into the screw terminals, and leaving it sticking out straight would have interfered with the case. I resolved this issue by attaching two more ring terminal crimps on one end and two small spade crimps on the other (hidden underneath badly applied heatshrink in the image):
The final adjustments I made was to use a JST connector terminal soldered to a small bit of stripboard to attach the fan and add female header crimps with housings (taped together with their male counterparts with electrical tape for a secure connection) on the heater wires, as I wanted these two elements to be easily detachable if needed.
I also made the decision not to ‘hack’ the original 12V power supply cable as suggested in the instructions but to use a screw terminal barrel jack instead as it seemed neater and more flexible should I ever need to replace the power supply.
At this point I would like to add that all of these modifications and build strategies were my own and should in no way be taken as gospel – if you do things in a similar way as described here when building your kit it is entirely at your own risk. I am still feeling my way around electronics and figuring out the best way to do things. Similarly, if you feel I made a mistake or want to suggest an improvement, please get in touch as I would welcome any constructive advice!
That’s my Filastruder fully assembled now, including cramming the finished electronics into the case. I have not had a chance to try it out yet, but I can safely say that I have finished the job to the best of my abilities. The Filastruder kit was certainly one of the more challenging things I have done so far, despite great email support from Tim. Can’t wait to get going now!!!