Hotend Swap and Increased cooling
Hello all, I have been working for the past several weeks on some prints running at roughly 22oC for 12 hours with an ambient room temperature of about 67-70F. In order to print with abrasives, I switched to an e3d hardened steel nozzle and had to adjust temperatures (increase from 215C to 225C ) to get consistent extrusion. This ultimately led to heat creep that jammed several ptfe tubes and many failed prints. I ended up ordering a new hotend ( https://www.matterhackers.com/store/l/e3d-v6-gold-hotend-full-kit-175-12v/sk/MEEFKJ6L?gclid=Cj0KCQjwyLDpBRCxARIsAEENsrK1n-W8Sor-GGM2Zy9jqRw5iHXeOX9-zo9pJIX4c7n5SBqWvewSGZUaAq27EALw_wcB ) as well as a titanium heartbreak to hopefully maintain better hotend temperatures. The gold heartbreak seemed over the top but the included wires and adapters along with the free shipping ended up beating out the standard kits price wise. Im also interested in using the fan included in the kit to cool the heatsink, and was wondering if anybody had managed to wire in a 3rd fan to their printer successfully. The fan is 12 V and once the kit comes I will either use the included attachment or come up with a mount to add the fan to the Pinda side of the extruder based on how it fits into the extruder. Has anybody used this kit and/or managed to add an extra fan successfully.
RE: Hotend Swap and Increased cooling
Is your existing hot end 12v? And will you be happy with a 30w heater instead of a 40w heater?
RE: Hotend Swap and Increased cooling
Sorry wrong link, https://www.matterhackers.com/store/l/e3d-v6-gold-hotend-full-kit-175-24v/sk/MQ36W84W I did order the 24V kit, and the heater is still 30W though but I don't mind the slower heat up time. I was incorrect before as well, the fan included is 24V as well
RE: Hotend Swap and Increased cooling
Are you sure the issue was heat creep and not just a blocked nozzle? Depending on the filament you might required to bump up the temperature even higher, printing slower and maybe even using bigger then 0.4 nozzles.
If you are not printing sand paper, the regular hotend should do the job.
Often linked posts:
Going small with MMU2
Real Multi Material
My prints on Instagram
RE: Hotend Swap and Increased cooling
I thought it was a blocked nozzle at first but upon taking apart the hotend, the jam was up in the ptfe tube, and upon further jams with replaced tubes the jams also occurred in the ptfe tube. My conclusion of heat creep came from observing that all my failed prints occurred after roughly 6-8 hours of printing. Im using glow in the dark filament as well as woodfill and had my brass nozzle chewed up by both on my last printer as well. Im hoping that the different hotend assembly with different values of thermal conductivity will combat the heat creep, and if not, adding a third fan was my next idea.
RE: Hotend Swap and Increased cooling
Glow filament is notorious for eating up nozzles; and it is also notorious for plugging nozzles. The bits of glow material are harder than hardened steel, and tend to collect in the orifice and when two or more try to exit a 0.4 nozzle, you get a plug. Many mfg's of glow suggest 0.8 mm nozzles for just this reason.
It's also why I stopped printing glow parts ... lol.
RE: Hotend Swap and Increased cooling
I thought it was a blocked nozzle at first but upon taking apart the hotend, the jam was up in the ptfe tube, and upon further jams with replaced tubes the jams also occurred in the ptfe tube. My conclusion of heat creep came from observing that all my failed prints occurred after roughly 6-8 hours of printing.
This conclusion might be not correct. After so many hours and maybe slow purge volume the filament will become softer in PTFE tube. A partial clogged nozzle will lead to higher back pressure. The softer material in the PTFE tube will build up first until the bondtech gears will start chew on the filament. So maybe what you've seen was a result of a partial clogged nozzle.
Often linked posts:
Going small with MMU2
Real Multi Material
My prints on Instagram
RE: Hotend Swap and Increased cooling
Haha thank you for the advice, I was printing glow in the dark for some parts someone requested and it was their top choice in filament, after this I may be at the same conclusion you are about it
RE: Hotend Swap and Increased cooling
I ended up taking my entire hot end to work today to use some tools their to take it apart and see what happened and I think you may be right. Looking at old ptfe tubes ive removed, heat creep may have been the cause. I talked with a colleague at work and they made the same point you did, and suggested that taking apart and reassembling the hotend so many times I may have been less than precise and the parts in the hotend were not snug to each other and filament may have gotten caught up somewhere inside and caused the most recent blockage.
RE: Hotend Swap and Increased cooling
The best advice for assemble comes from E3D. They have two papers on how to assemble the V6 and nozzle. They are suggested reading before working on the MK3 extruder ... based on personal experience.
Search their page for V6 nozzle replacement and V6 assembly.