I don’t know if proper procedures were followed when taking off the nozzle, since at my school I print more than anyone, but they still think taking it apart past the point of the heatshrink is a job for the adults… however when taking it apart and putting it back together I do not know of any specific method or way that the teacher was following. I get the feeling there is some kind of issue or loose bit in there… It seemed like a really rushed job to me, and I already had to tighten other screws.
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Hey Logan,
If you are in the LA area then go ahead and bring it on in our shop and we can see about fixing this issue you are having.
-Maya
The Build Shop
Hi,
If you have had the unit apart one thing worth double checking is that the fan on the front heat sink has not been installed back to front. When its the wrong way around the PLA will overheat above the heater block and become too soft for the feed roller. Eventually (10-15 Minutes into a print) it will stop extruding. There will be a mess around the feed roller that needs to be cleared. Sometimes the PLA can be seen feeding out of the side near the stepper/feed roller area above the heated block.
This. We’ve diagnosed a few “broken” Rep 2’s that just had the fan mounted in the wrong direction.
Yup somebody messed up the head most probably. Have you been running regular maintenance? Do you have the new spring loaded mechanism to push the Filament in the Extruder against the gear to push it out? What’s happening is there is now a gap between the heated Filament and the Nozzle so the Filament bends and extrudes out from another outlet created during the messing about with the head.
I use Goof Off heavy duty wipes and AR Kleen Lens cleaner to keep the extruder going once it clogs. Have not had to dissassemble as of yet - and have a standby extruder on hand just in case.
I am located in Chantilly, VA. If not too far from me, I could come by and take a look.
First, it looks like you are working on a 2x. I also dont see anything from the picture.
It does sound like your nozzle is loose. Someone might have stripped out the threads! In that case you might need a new nozzle and aluminum block.
Hey! Glad to hear it’s working well for you!
Time to redo your hotend. disassemble it and replace the inner PTFE tube (3mm outer, 2mm inner diameter).
How to: unscrew the 2 lower bolts that holds the fan, heatsink and extruder, on the long cooling aluminum block there is 2 locking bolts that holds the hotend barrels in position, loosen them up and pull down both barrels. Loose the lock bolts that secure the heater resistors and the thermocouples, separate the barrels from the heater blocks and also take out the nozzles. Replace the inner tube with new ones and cut to size, cut out the insulation tape from the heater blocks and clean and run the correct size drill on the nozzle. Put all together again and install in position (do not assemble the extruder yet), once in position cover the heater blocks with Silicone tape from Autozone or any hardware store that sells them (they are for hot water pipes), run a bed calibration command from the printer and it’s first point, set both nozzles at the correct distance from the bed and then tight the locking bolts, finish running the calibration and once done, you can finish assembly the extruders. (It is a good advice though to open the extruders and clean the gears).
You are done for the next 3 to 12 months depending on how much you print.
11 days later
Just an update folks…I believe the print head was simply not screwed together properly. The teacher who works on it soaked the nozzle in acetone for a long amount of time, ranging between a few days and over a week. There was a bit of PLA left, but that came out when it heated up so it looks good. He was finishing assembling the whole thing today when I left school, and I am scheduled a bunch of times in the next few weeks printing, so I’ll update with the results. I plan to bust out 3+ prints tomorrow alone, so I should see how it ends up relatively soon. Thanks again for all the tips!
PS: The job I left printing just for the heck of it (when there was a slow but steady leak) actually printed perfectly! As I had hoped, I had removed enough of the leak so that when the job finished the leaked amount did not fall off of the print head and mess up the print. I’d guess it leaked around 10 g over the duration of the 3hr print, with a m&m sized bit of pla hanging out every 30ish minutes. I think there was a minor clog, and that combined with too large of a gap between parts was leading to liquid material seeping out where it shouldn’t have. Hopefully will be good now.