Compared to Jhead does the hexagon need to run at a higher temp for ABS

[roybfr]

I recently switched form a Gregs/Jhead setup to a Bulldog Lite / Hexagon setup. After several prints I started getting jams/clicking from the extruder. The hobbed gear on the extruder was always clean and free of debris and I confirmed the filament path was straight to remove those as being the issue. I cleaned the hexagon out twice and there was never much in the way of clogging. The issues are not happening right at first but after a few minutes of printing. So wondering if I need to up my temp as on the Jhead I ran ABS at 225 without issues and used that as my starting temp on the Hexagon. I wonder if the temp is dropping enough on the Hexagon that the ABS is not melting all the way as I noticed it was a little tougher to manually push it through then with the jhead.

[joop1987]

I had a similar problem that I solved by setting the Retracting, Minimum travel (mm) from Cura's default 2.5mm to 1.5mm. I guess the soft ABS was getting stuck in the Teflon tube inside the "all metal" Chinese extruder.

[printbus]

Lots of variables involved here that you could clarify. Same size filament between the two? Are the nozzle orifices the same between the Jhead and hexagon? Safe to assume the extruder was recalibrated after moving to the Bulldog/hexagon? Is the comparison being made on a fairly similar print as far things that would affect filament volume vs time (print speed, amount of infill, etc.)? Was the heater cartridge moved from the Jhead or a different cartridge heater used in the hexagon? If different, are they the same power?

I also assume the same thermistor wasn't moved from the Jhead to the hexagon. My take is that the thermistors provide a fairly good *relative* measure of temperature change, but not necessarily a highly accurate *absolute* measure. Not sure how much comparison you can make between what one hot end & thermistor measure and another.

[roybfr]

Is there teflon inside the Hexagon? According to MF site and other places it is all metal. The jam was not surprising see the issues others have had with this hot end. I noticed MF is going the E3D route and has Hexagons on sale. My Jhead is on there now and after tuning the PID I extruded ~ 300mm of filament with out issue. Will get the z height reset tonight and do a test print to see if the same issues comebeack

[roybfr]

Filement is 1.75 on both, in fact same exact spool. .40 noddle on both. After installing the Bulldog I reset the steps to what the bulldog recommended then did a calibration to make sure it was correct. Different heater cartridges and thermistors, latter have similar specs but the heater cartrige/resistors are different, 3W vs 30W.

Not so concerned about 225 being the same one both, guessing they are close but not spot on. Just curious if others had to run their Hexagon hotter then the JHead.

[printbus]

No, there's no teflon in the hexagon. It is truly all-metal.

Yes, a number of people have had problems with the hexagon hot end extrusion stopping, at least when used on the Wade Greg's extruder. My latest attempt at a recap list of reasons people have came up with over the last year+ was provided in the Extruding Problems thread. Some of these causes would apply to all hot ends and not just the hexagon. Some are specific to the Wade Greg's, some aren't. One thing that is unique about the hexagon is that it appears to have a bit narrower feed tube than other hot ends, making it sensitive to bumps or excess diameter in the filament.

I know in my case issues with the Greg's and hexagon extrusion stopping went away with time. Whether that was simply due to me becoming smarter as a user vs. something more esoteric like the hot end conditioning with use, IDK.

[roybfr]

Are you running PLA or ABS, and for what ever you run what do you use for temps?

[printbus]

Are you running PLA or ABS, and for what ever you run what do you use for temps?

I haven't been pushing the limits with the hexagon, if that's what you want to know. I purchased it for the ability to get into some of the high temp filaments, but never got there. ABS printed long ago was in the 230 to 250 range. For quite a while, I've been focusing on PLA prints. Temperatures vary between maybe 205 and 220, depending on the filament, the amount of layer detail involved, and the strength I want to achieve in layer adhesion.

I also moved to the e3dv6 about a month ago. For 1.75mm, that DOES have a PTFE feed tube and is sensitive to retracting hot filament into the PTFE tube and plugging it if it is left there to harden.

[roybfr]

I am back the jhead and so far no issues, if that keeps up then I know it was on the Hexagon side of things. I will swap it back in and kick up the print temp 5deg at time to see if that solves the issue. I still think it prints a little cleaner then my old jhead so would like to get it working with minimal clogs.

[Chadd]

I have only had jamming problems twice with my 3mm hexagon. One time was related to me trying to run ABS while having the temp profile for PLA loaded. The second time was with PLA because the hotend cooling fan wasn't moving enough cooling air over the heat break and the PLA was melting up inside the heat break.

I would take a good look at your hotend cooling fan setup as from what I read that is the culprit of most hexagon jamming issues.

I am back the jhead and so far no issues, if that keeps up then I know it was on the Hexagon side of things. I will swap it back in and kick up the print temp 5deg at time to see if that solves the issue. I still think it prints a little cleaner then my old jhead so would like to get it working with minimal clogs.