This is a new one. I have a Robo3D and after several hours finally got the E3D head installed by following the assembly instructions on the E3D documentation website. Everything was assembled, and I changed the Marlin software for a maximum temperature of 300, and changed the value for the thermsistor to 5. It took quite a while to heat up, which I just attributed to the fan running continuously as the instructions say to basically wire it into the mains. Unfortunately, by the time the extruder was reading about 260C, the entire thing melted down. There was no short in the thermsistor. It was inserted appropriately into the heat block. So basically, the heatsink failed with the fan running. The head melted itself. The thermsistor was (presumably) bad. It also melted part of my X-carriage, but I can ask Robo3D to print one of those and send it to me. So, needless to say, I'm not too happy. There is no way that the thing got that hot with the head (or more accurately, the thermsistor) functioning appropriately.
Can you post an image of the hot side of the hotend - showing how the heater block etc are assembled?
Sure. The only thing that isn't "standard" is the small screw I placed to hold the heating element as the one shipped disappeared into the carpet somewhere. Note that this is after I tried an unsuccessful salvage operation so things are sort of cobbled back together.
Sorry for not having replied to you sooner - things have been a little crazy here. Whats happened here is that the heater block was assembled very high up the heatbreak/nozzle, thus bypassing the thermal break and allowing heat to flow up the system unchecked. If the hotend is assembled as per the documentation you can run the temp up so high it will melt the aluminium block right off the hotend without ever damaging your printer or fan duct. It looks like you're pretty well on your way to getting back up and running - but you absolutely need to move the block down the threads so there is just a small gap between the block and the hex flats of the nozzle. If you need any more help please do post again! Regards, Sanjay
