Friday 3 January 2014

Building the Thing-o-tron Part Three: Heated Bed and Filament Drive

And so it is time to get the soldering iron out. I've not done any soldering in anger for years - in fact probably nothing serious since the microelectronics practicals at uni. But the heated bed needs assembling now, and that needs a couple of components attaching.

The led to show when the bed is powered (and its resistor) are soldered to the small holes on the edge, and then the power lead for the bed is soldered through the larger holes. Finally, the heat sensor is soldered to a lead and fixed in place in the centre hole under the bed.

A quick check with the multimeter shows the right values so I appear to have good enough connections rather than shorts or dry joints.

Finally, the metal sheet / circuitboard / fibreboard support sandwich is screwed to its y axis mounting points. We'll see if it all works later, when the wiring up is done.

With that out of the way, I can now build the filament drive. This will pull the feedstock from its reel and push it to the extruder hot end for melting. It all fits together pretty easily - a couple of cogs and a bearing to allow the stepper motor to pull the filament, an adjustment screw to loosen/tighten the grip on the filament. Then the whole piece fits onto the top of the frame with plastic clips.

Not much to do now - just the hot end and then its wiring up time!