A while ago Wanhao was reaching out to its customers and resellers, warning them of a design flaw in their Duplicator i3 that may cause fires. The printers suffered from an issue that caused crimp connections of the nozzle heater cartridge’s supply line to fail due to the mechanical stress in the cable drag chain. In their “Recall” titled note, Wanhao provides instructions on how to fix the issue.
According to Chuck, the heated build plate’s leveling springs feature sharp edges which cut through the soldermask of the PCB heated platform and make contact with the traces and the metal carriage. That issues alone wouldn’t cause the short, but in certain positions, one of the Y-axis’s belt holder mounting screws seems to rub against grounded metal parts of the printer, temporarily grounding the carriage.
The issue is hard to spot at first glance and may affect the Duplicator i3 and the i3 Plus. A lot has to go wrong before an all-metal 3D printer catches flames and all mentioned issues incorporate non-lethal voltages. Nevertheless, be safe. If you own one of these, now is the time to check your machine for potential failure points. [Chuck] provides you a quick fix for the spring issue in his video below!