The way the head mechanism works is incredibly simple: filament is fed through the guide hole at the top and it's pulled through into the heater block by a stepper motor with a grip wheel on its shaft.
The grip wheel takes one side of the filament while a plastic plunger pushes hard on the other side so the grip wheel can grab the filament and feed it into the heater block at a constant rate.
The heater block heats up to 230°C, melts the filament into its own little reservoir tank and it starts oozing out of the extruder nozzle at the bottom.
On pulling the head apart, we found a small piece of filament stuck just between the grip wheel and the top of the heater block. Once that was removed, we put the head back together and away we went.
The other thing we discovered is that no 3D printer likes the arctic conditions of the TechLife Labs, normally designed to keep desktop PCs cool. Once we got it back to normal room temperature, the Replicator 2 didn't miss a beat.
Had this been an inkjet printer and we found a fault, we would have sent it back to be repaired, but the fact that the Replicator 2 is designed to be pulled apart (and includes the tools for doings so) is a real plus in our book.
You need to be a little bit brave and lose the 'can I really do this?' fear because the more you understand how the printer works, the far more confident you'll be to handle almost any eventuality.
The one thing we reckon MakerBot could do better is to make a larger retaining bracket for the cable tie that holds the main cable sheath to the side of the print head.
Ours had clearly popped out during shipment from the US and there was no way to get it back in. A proper-sized groove on the top of the print head block would solve this instantly.
Pricey, but solidly built
The Replicator 2 comes in at $2,540 (shipping included) and while that's quite a bit more than the UP Mini, we do love that it's solidly built and unlike most tech these days, is designed to be user-serviceable.
With its huge 28.5 x 15.3 x 15.5cm build space and low $40 per kilogram filament spool pricing, I can see I'll have to put up a sign on the TechLife Labs door saying: 'All orders in before 9am'.
Find out more about the 3D printing revolution in our May 2013 issue of TechLife magazine. It includes a 3D Printer buyer's guide, a step-by-step guide on how to get started on 3D printing, plus more.
Watch the Makerbot Replicator 2 at work:
