Welcome to the SeeMeCNC Community

Great news, I finished assembling my Rostock V2 Max. However....

I was extruding my first ABS plastic, and everything seemed to be going fine... temp looked good at 225 deg, and plastic was extruding but there was a lot of smoke/steam coming off the plastic and it looked somewhat off colored and brittle as it extruded. This was a fresh role of ABS 15 minutes out of the new plastic bag and it measured about 1.78mm average diameter.

After the initial extrusion, I had clicked the manual extrude button in Repetier multiple times intending to extrude enough to really prime the extruder for the first print. Then the plastic stopped extruding. I clicked the manual extrude button a couple more times and that is when I noticed that plastic was coming out the side of the extruder. See attached pictures.

I assume the extrude is broke. Any advice on what went wrong and how to fix?

Thank you for any help...
Mike

Looking at the "front view" picture you posted, it looks like the thermistor came out of the hotend, causing the hotend to go into a thermal runaway, causing the PEEK tube to melt.

I agree with the previous poster, you'll either need a new Hotend, or you can replace the peek section and the liner.
FWIW this is how I lost my first Hotend, the silicon won't bond to the heater block, so you can't rely on it to keep the thermistor is place.

Polygonhell wrote:I agree with the previous poster, you'll either need a new Hotend, or you can replace the peek section and the liner.
FWIW this is how I lost my first Hotend, the silicon won't bond to the heater block, so you can't rely on it to keep the thermistor is place.

I would suggest either a Screw-In Thermistor or to wrap the installed thermistor with a Silicon Tape "wrap". This will stand the heat of the hot end and keep the thermistor from slipping out. The RTV is not intended by the manufacturer to be an adhesive. It also does not stick very well and peels off.

nitewatchman

Thanks for the responses. I agree, especially after disassembling the failed hot end none of the RTV was sticking to the metal. I ordered the E3D v6 hotend. It looks easier to assemble and has the screw in mount for the thermistor. Might want to update the Rostock Max V2 assembly instructions to emphasis thoroughly taping the thermistor in place.

Thanks! Can't wait to get my new hot end and give it another go...
Mike

Is it possible to unclog the original hot end nozzle?
Is the E3D v6 hot and direct fit for the Rostock Max v2 or are there other mods required?

Josshe wrote:Is it possible to unclog the original hot end nozzle?
Is the E3D v6 hot and direct fit for the Rostock Max v2 or are there other mods required?

Of course. Clogs are a pain in the ass, but common enough. There are numerous threads on here describing how to unclog the hot end.

What I did was remove the brass nozzle then gently heated it with a lighter and used a small drill bit to pull out what's left of the filament. Be careful not to gouge inside as the brass is very soft. But eventually working at it, you should get it to the point where you can see light through the nozzle.

After disassembling, it turns out the head was not clogged. The failure does appear to be thermal runaway causing the peek to melt. The plastic took the least resistant path and went out the side. The hot end nozzle is completely usable.