21

Good point - sometimes you oversee the simplest things. ‘Unfortunately’ for me - I didn’t :slight_smile: (1.75 is in the settings)

22

Yeah, it still could be the issue even if your motor doesn’t tick. The ticking is from heavy resistance that overpowers the motor.

I’m still not sure what the exact cause was. I’m leaning towards temperature issues though because it’s as if the melt zone never reached the tip anymore. I cleaned the crap out of that thing and it still jammed so I can’t think of what else it would have been.

When it got to it’s worst, there was a weird symptom when it got jammed. I wouldn’t be able to feed it by hand unless I pulled the filament out, trimmed it flush and reinserted it. That made me thing the tip wasn’t getting hot enough anymore and the filament was solidifying at the tip. So when printing rafts and simple parts, it would print fine because the flow was constant. The jams would start when there was constant retracting in the print process - so the filament at the tip just sat there and solidified.

My issues started when I used a new spool of filament that I just so happened to buy on eBay. I can’t prove it was the cause and it might have only been a coincidence. Needless to say, I threw that spool out just in case. With that spool, I had a bad print which somehow caused the print to detach and stick to my nozzle. This saturated the fiberglass sock with plastic and may have contributed to my issue. I tried flipping it around to see if the heat was being released too fast, but it didn’t help. It’s possible some plastic got up to the thermistor but I haven’t checked yet. One person in another thread suggested that I hadn’t screwed the tip on all the way. Thing is my issues started before ever messing with the tip. I could have made it worse by doing that though. Also, when you disassemble, make sure you have some spare ptfe tape for the tip. They use it on the threads.

1 Like
23

Can you post a picture of your hot end? Not familiar with the Printrbot, but this kind of sounds like an issue i experienced.

24

This is the hot end I use. http://printrbot.com/shop/1-75mm-ubis-hot-end/

I’m waiting very impatiently for the metal one to come back in stock… :slight_smile:

25

does it come apart? I took my nozzle apart last night (different kind) and thought i had it back together, but i was having issues with it not feeding, checked it while it was hot and it was not all the way back together, there was cooled plastic in the threads during reassembly. There was a space between the barrel, and the nozzle, which was catching the filament and not allowing it to make it to the nozzle. I disconnected the hot end from the “x” carriage and let it heat up to temp, and re tightened everything. Worked like new after that.

26

Mark,

I had the same issue with my printer this weekend. Turned out the room was too hot! (because of this heat wave in Central Europe) The fan on my extruder couldn’t handle the job and this caused the filament to overheat and melt in the upper part of the extruder, causing a blockage. I started noticing gaps in my print and it got worse. When I extruded manually, it worked fine, because the nozzle only warmed up temporarily. When printing automatically, the extruder overheated after 10-15 minutes.

Then I moved my printer to the cellar (where it’s still cool) and everything worked just fine! Since you mentioned that the problem started when you moved your printer, I thought this may be related…

Hopefully you’ll find the solution! Remember, from every problem you’ll learn something :slight_smile:

Pieter

27

Did you get this figured out?

A few other possibility

  1. Printing too close to the bed
  2. Clog in the hot end
  3. Clogged extruder hob ( eg bits of plastic in between the teeth )
1 Like
28

Hi Derek,

Thanks for sharing your story!

It sounds indeed you had a heating problem.

My extruder heats up well - I got burned by it the other day ^^

-Mark

29

Hi Bilisch,

Thanks for bringing it up!

1 and 3 I have checked - those are fin.

2: it doesn’t seem so - but nonetheless I will take it apart and clean it out.

30

Hi Pieter,

I know about the heat wave - I was in the middle of it :wink: (nl)

I’ve read before that the room temperature affects the printing process - especially the quality of the filament. Direct sunlight and a high humidity are killing.

Sadly my problem isn’t temperature related - so I will look further. Thanks for sharing anyway, interesting!

-Mark

31

Hi Ian,

Even for PLA I use my beloved heated-bed. There is only one thing worse than using a glue stick for adhesion and that is blue tape ^^. The problem in the picture was under-extrusion; not enough filament to stick to the bed so it got loose

The sliced models are fine - and I set first layer print speed on purpose on 20m/s.

The M503 is a great tip to check if your motor is set to the right amount of steps per mm! :slight_smile:

Just to be sure I unscrew the ‘tensioner’ and put it back together - along with removing the nozzle and cleaning it out that solved my issue!.

I appreciated your thoughts!

-Mark

32

UPDATE: as many suggested I removed the nozzle and cleaned it out. Same for the the ‘screw’ part on the extruder. I checked every screw and tighten it where needed. Furthermore I took the ‘tensioner’ apart and screw it back together.

That worked!

Here is a freshly printed bunny to thank you all for your suggestions!

20150713_133855.jpg
20150713_133855.jpg3840×2160 2.98 MB

2 Likes
33

Cool, glad you got it figured out. There is a really nice resource over at bukobot that I have been using for a while now and it works great. Lots less painful than a full tear-down.

nozzle-cleaning [Bukobot 3D Printer Instructions & Docs] Its a really great article and shows exactly what to look for. I have found this necessary especially if going from a very high temp material to something like abs or pla as the nozzle still has a little material in there which can cause flow problems/increased back-pressure in the hotend.

34

I’ll definitely give this a try

35

wooooooo nice to know that it works! Great job buddy ! Also, for the printbot, i dont know if somebody told u earlier but when u do longer prints, u must have a cooling system for the extrusion head, for avoid clugs. Like this Extruder Fan Mount for Printrbot Simple by drewsloan - Thingiverse

Have a nice day

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36

It’s almost silly for me to ask but a lot of problems on my printers arise when the fan that cool down the extruder start failing, almost imperceptible; most of the time when you are not there but it makes the filament softer and thus to under extrude. I’ve been through more than a dozen of those. They still work but they are not that smooth, same on the CTC with the PCB fan.

37

I used a few old 12v computer fans to blow on the Printers to keep them a lil cool. They can get pretty hot on long prints. A small 12v and put the bot on some feet to allow air travel to pass under the bot.

Keep it cool,