Bowden tube broke away from extruder mech

[burningbeard62 0]

Hi,

I've done a bit of digging but can't find any post on exactly this topic. My bowden tube, normally locked in place in the extruder mech via cutaway slots in the plywood mount and the locknut plastic screw fitting, has broken through those locators and free of the extruder assembly completely, stopping extrusion.

I think the cause of this problem was increasing the flow too much, in error.

See attached photos. This breakage is very disappointing. Is there an improved extruder assembly I should use instead? Probably I will just epoxy the fitting back in its location, which will do for now. It would have been better if the unit failed in some other more reparable way to this issue of too much 'flow'. Thoughts and comments appreciated.

http://tinyurl.com/m92rojp

 

[illuminarti 18]

Oh, eek. That's not good :-( Sorry that happened.

I haven't had that problem, or really heard much about problems with the Bowden attachment on the cold end of the tube... but evidently it does happen. Have a look on thingiverse for possible fixes. For instance, something like this might help... (once you're able to start printing again... perhaps you could clamp the block in place somehow long enough to print a fix? I'd be wary of glue as it might preclude taking it all apart later for other fixes/upgrades.

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

Oh, btw, I highly recommend getting the v2 extruder clamp upgrade with the spring-loaded pressure plate. It definitely solves a lot of problems, and would probably have helped in this case, by giving some room for the filament to slip back past the drive bolt when running excessively fast, rather than continuing to cram filament into the tube until something had to give.

 

[burningbeard62 0]

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

Thanks for that recommendation - it looks like what I need!

Oh, btw, I highly recommend getting the v2 extruder clamp upgrade with the spring-loaded pressure plate. It definitely solves a lot of problems, and would probably have helped in this case, by giving some room for the filament to slip back past the drive bolt when running excessively fast, rather than continuing to cram filament into the tube until something had to give.

OK, I will look into that too.

 

[burningbeard62 0]

I have managed to reasseble the extruder and printed off this retention mod. Its seems to work very well! See http://tinyurl.com/m92rojp for some additional images of the reassembled extruder with mod. I have also checked into the extruder upgrade which makes it work well with filament thickness variation and look forward to getting it in future. I bought some cheap reels a while back that never worked very well as they were lumpy and uneven. Maybe with the upgrade I can use them. Thanks again for the pointer Illuminati!