J-head all metal extruder keeps jamming.

I have made my own reprap printer. I've finally finished it and now I'm having an issue with this bots hot ends I've never encountered before. I have a all metal J head extruder with a 0.4mm tip. I am pretty sure all my settings are correct as far as size and type of extruder my set up is running. The issue is every time this bot goes to fill "infill" it will begin to jam. I've raised and lowered the extruder to see if it was too close to the bed, I've changed the temp, extruder feed rate, nozzle size and even added a box fan a long with another smaller fan to keep better cooling in case the extruder was over heating. None of this has resolved the situation. I've tried other extruders and they have done the same thing, there all j head all metal but made from different people and still have the same effect.

When a jam occurs I try to get the filliment backed out while the extruder is still hot as fast as possible so I dont have to dismantle the the entire extruder to clear the clog. When I get the filliment back out the end seems swollen up and then stretched from me pulling to get it back out. I'm not sure if this will hep to identify the issue or not. I've got another bot that is just like this one but a little smaller sense it was my proto type and it has never had any issues extruding.

Where did you buy this hotend? Metal J-heads are often made by cheap knockoff companies and will be unreliable from the start. If you really don't want to spend the money for an E3D (or an E3D-lite), try disassembling the hotend and cleaning it out.

I got them off ebay. They work fine on my other printer I don't get it lol.

here is a rework video for those chinese clones. I have been running mine with no issues since doing the rework.

[www.youtube.com]

---

My Personal Blog. Build blog.
[engineerd3d.ddns.net]

Modicum V1 sold on e-bay user jaguarking11