Bowden cable keeps popping out of the quick-fit coupling

[mich 0]

Hi all,

I am a proud new owner of a few weeks old Ultimaker. Until now, the machine has been performing fine and as a newbie, I've learnt quite a lot these past weeks. :smile:

Recently however, I am not able to print anymore, as the Bowden cable keeps popping out of the quick-fit coupling all the time. I did replace the tape around the Bowden cable (I came prepared like that from Ultimaker) and put it in tightly, but that does not help. The feeding is fine, the filament goes forward nicely, but I guess that the friction is simply too high when it passes from the feeder into the bowden cable. It seems that the QFC is simply not able to keep the Bowden cable fixed.

The filament i currently use is the grey PLA issued by Ultimaker. All the rest of the hardware is Ultimaker, no tweaks so far. I've been reading a bit in the forum and it seems that this is quite a common issue.

I've also found these two solutions:

http://www.thingiverse.com/thing:10799

http://www.thingiverse.com/thing:40544

I'm a bit uncomfortable with putting screws into the feed mechanism, so does there exist another solution? What did you guys do and what works best in your opinion?

Thanks in advance for your answers,

Mich

 

[msurunner 2]

So you have tape around the bowden where the connector bites? If that's the case, I would remove it. If you are having issues where the filament is grabbing the edge of the bowden tube and pushing it upward, you can try taking an angled razor and scrapping the inside of the bowden to increase the chamfer slightly. You don't have to worry too much about if you screwed it up, as you can trim the 1/2" or so that you can screw it up off and still reach all of the parts of the bed.

 

[francis 0]

Hi Mich,

The tape does not belong there. It is to indicate which end of the bowden goes where and should be removed. I had great succes with this thing:

http://www.thingiverse.com/thing:46157

and easy to try.

 

[gr5 2,265]

Also what temperature, speed and layer height are you printing at? For example 200mm/sec .2mm layer height, 190C will have incredible pressure in the head and more likely to pop off the tube whereas 240C, .2mm layer, 100mm/sec is low pressure and not much force on the tube.

 

[owen 19]

This thing works . http://www.thingiverse.com/thing:17027

 

[mich 0]

Thanks a lot for the quick answers guys.

Unfortunately, its going from bad to worse. So far, I've removed that tape and I scraped the inside of the Bowden cable with a razor, to reduce chafing. This did not help, it's seems to be popping off even more often.

As for temp, speed and layer height: I've been printing with PLA, 100mm/sec max or slower, .1mm layer and around 210-220C.

And I've tried to print the diverse solutions you proposed, but the cable always comes off during the print. I even tried to hold it manually, but I don't want to force anything. Anyway, it came off again.

I did manage however to print the Ultimaker extruder clip (http://www.thingiverse.com/thing:46157), but it broke when I tried to put it on. :-| Now that I've changed to ABS, the Bowden cable comes off again.

I'll go to our FabLab tomorrow and print a few of the parts in ABS there. I'll keep you posted.

If you got any other ideas, I'll take them... :mrgreen:

Thanks for the help anyway.

Mich

 

[owen 19]

If you put a 7mm tap on the end of the bowden tube you can than put a nut on it and than be able to hold it down while you print a solution. I actually use http://www.thingiverse.com/thing:17027

but with a nut inside instead of the tightening cone so that the bowden tube doesn't get squeezed.

 

[msurunner 2]

Temp sounds a bit low for 100 mm/s (context, I'm usually at 220 with about 50-60 mm/s). For the sake of troubleshooting, when are you getting the pops? Immediately? Five minutes in? 30 seconds? If you need to print something to make it work, you are likely going to need to slow it down to the 50-60 range until you get 'er dialed in.

 

[phanc60844 0]

Is your nozzle digging into the bed? This causes excess pressure in the nozzle which can cause the tube to pop off ,make sure there is a paper thickness gap between the nozzle and bed.

paul

 

[mich 0]

Hi guys,

Thanks for all the quick answers. I've now managed to print on a friends printer an Ultimaker extruder clip (http://www.thingiverse.com/thing:46157) as recommended by Francis and that works fine. I've been making some "torture tests" and so far it did not pop out a single time.

Thanks again for all the support, great community here!

Mich