E3D V6 known flaw back again

The E3D v6 3mm has a heat creep flaw that I’m still working out, however it seems that they knew about it in the boden style 1.5mm V5 which included a PTFE tube which needed to be installed inside the feeder tube of the extruder and then trimmed to fit at installation.

The same problems reported on the E3D web forum concerning this are the same I have been seeing. Basically, it’s like this, printing fine, layers good, and you get into a more complex retraction area and the melted stuff makes a cloggy bit up the tube where you can see that it separates and then causes a strip and jam. Then nothing but whispy to eventual complete extruder fail. After 20 or so re-tries I’m posting this issue here and there so everyone knows. Heat creep, maybe fixable with a more powerful fan on the E3D or perhaps with a redesign, I haven’t printed in ABS with it yet, only PLA.

The V5 1.5mm boden extruder addressed this with an insert-able PTFE tube, like the one used in the Buddaschnozzle but smaller without the pooling seen on the heater block.

I will likely have to find a different extruder as the E3D doesn’t like long complex prints in 3mm, maybe the reprap hex one will be next.

Doesn’t the PTFE tube defeats the purpose of the all metal hotend?

I am near getting my Hexagon hotend.
Meanwhile here is a useful link from someone who is already using it-
http://forums.robo3dprinter.com/index.php?threads/hexagon-hot-end.1888/

defeat? hmm prevent heat creep and jamming? Yes. all metal hotend may not be the best idea, in fact I would now vote against such a thing until redesigned to work.

I am not sure you’ve understood me-
HEXAGON HOTEND-
“…Since there is no PTFE or plastic to be found anywhere in the hot end it is safe up to 400C which is much higher temperature then most hot ends with PTFE linears that max out at about 245C tops…”

PTFE melts at around 300Celsius and that means you cannot print in Nylon, Polycarbonate and similar materials that require this high of a temperature

How much active cooling are you using on the cooling fins for the hot end? Make sure you’re running at the highest speed you can use without having more back pressure than forward flow.

Sorry to bump back an old thread, but just curious - what are your retraction settings?

Yeah heat creep can be troubling in an all metal hot end. But stainless has pretty low thermal conductivity and the way the heat break is designed is pretty effective in controlling heat up into the filament. With a non-bowden extruder and an e3d v6, your retraction should be small enough that this shouldn’t be a big problem! On a bowden setup, with the flex of the filament inside the bowden tube, this is a lot more tricky…

well it was 2.5mm @ 6mm speed, tried a bunch of different retraction amounts, if I hit 1 it would jam after only a few layers, if I went more, it would eat the filament with the hob bolt. 1.5-2.8 worked on the budda, and it used to work on this one, I have printed LOTS of nylon with it, but that was at a much higher temp, and jams were rare, delamination and print warping were the problem with nylon.

On the E3D forums I found that the “temporary” solution was to oil the extruder tube, but that would only last for a short while, cusomers saying only 1 print.

I noticed that the filament would jam at approximately the same duration depending upon the retraction, temp and speed of the retraction, but the result was the same in all cases, the end of the filament would get stuck somehow and upon retraction, would form a hard pill that became wider than the throat leading to the heater block, and the filament would get crooked and then the hob bolt would strip.

The filastruder rep tried to blame rapid, multiple retractions in an email, but also stated that the oil fix wouldn’t last long either. I found that the rapid retractions on pillar supports generated by Meshmixer caused some jam and strips, but the most recent wave of failures were on continuous flow prints that at first would go a while (2-4 hours) but if the head was already hot, and it stripped, the amount of time till another failure was shorter and shorter which fits with what I was pulling out of the extruder body, a filament with a crooked zigg-zag from the extruder motor pushing and it not going anywhere with a large bit of filament like a ball on the end, while on others it was a separated bit that seemed to stay jammed in the head, while the filament pulled away from it, which lead to a jam in a few more retractions, 1-3.

Either way it looks like the design is flawed, I hope the reprap one uses wider fins and a bigger fan, I’m thinking about trying that one next and in the meantime going back to my Buddaschnozzle with it’s PTFE guide tube. I found this on the forums which looks specifically at the 3mm E3DV6 and an issue with the feed tube diameter.

The forum link is: http://forum.e3d-online.com/viewtopic.php?f=13&t=177&start=90

it looks like a manufacturing problem they may have made the end of the tube too small, the fix would be: enlarging it to 3.3mm all the way through and removing a small step that remained from machining.

Ogrethetoymaker

I switched back to my buddaschnozzle and wow what a difference! 8 hours, no issues! No more jams like before, unless you’re printing nylon or hotter, the original extruder works very well, much better than the 3mm E3Dv6. The older E3D, PTFE lined 1.5mm was lined with teflon for a reason, it worked. now E3D is scrambling to replace parts in my E3D and “make it right” but ya know what? I like printing in PLA and I don’t need the hassles. Like my old Honda which leaked a bit but was the most reliable car ever, I’ll just use Q-tips to clean up the heater block on long prints.

Ogrethetoymaker