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I am looking to upgrade my bowden tube and couplings. The amazon link I have found on youtube from CHEP and others is for 10 sets (20 piece) and made me wonder if they should be replaced every so often. If so, How often should they be replaced?
https://www.amazon.com/gp/product/B0...d7c9d91cdf2787
If you have to disconnect your bowden tube for service reasons, the connector can become difficult to release or in a worse-case situation, not properly grip the tubing. The tubing should hold well enough unless physically damaged.
I have a dual extruder bowden system and old filament or poor quality will sometimes break within the bowden tube. I have to release both ends and clear the section, then put it back together. Even after three years of this, I've not had to replace the connector, but did have to replace a tube after my own ham-fisted actions.
just depends on the quality of the original fittings.
My mini-delta comes with dirt cheap couplings that seem to break a lot.
I guess the answer is: change once if crap, and never if good.
I love this subject as it is rarely considered and only a moot issue for many.However, I run replacement tubing on a system that wasn't intended to use them.Furthermore, this system requires the extruders (2) to be installed using a 135 degree rotation.
And on the spool side is a cartridge bulkhead that come off the printer and of course, the bowden tube comes along as an umbilical cord.So here's the real deal with all push-to-connect fittings; the grippers are sharp; they grip a sharp edge into the material; they rarely rotate freely; and they leave a nasty groove in the bowden tube if you twist the tube in the fitting. This is when the tube gets stuck.... and this is when the fitting grippers break due to lack of options - you yank on it.
Again, umbilical rotates on cartridges when changing cartridges; fail!
Remove extruder by ccw twist of 135 degrees and ; fail!
No matter how hard you try, this failure mode was plaguing me on my Cube3's. I went through nearly 2 dozen when I said enough! Bowden tubes were getting shorter and shorter. I needed a solution.
I came up with one but that's not the point of the comments; the point is, as Aardvark pointed out, good and bad fittings. The failure mode described here is only to say that PTFE tubes in Push-to-Connect fittings are not sanctioned by the fitting manufacturers (OEM's based on design criteria, not copy cats wanting to sell product) and do cause this possibility of getting 'stuck' in the fitting if the tube is rotated. Not an immediate failure mode, but in short order it will wear a groove deep enough to catch the grippers.
@TommyDee, I have a Cube3 and two cartridges still in OEM wrapping. Our local library has given up on theirs, although it was working great the first months of operation. So well, I bought one. Now that I've gone through the grief of helping them keep theirs working, I've put mine in a corner (closet) collecting dust.
I've tried to follow the threads that provide for upgrading and improving the printer, but I've gotten buried by the substantial differences in the various messages.
It would be great if there was one comprehensive "instructable" for converting the Cube3 without replacing stepper motors or controllers but modifying the nozzle and feed system is reasonable.
What's a good route to take in that respect? Are you willing to give away your secret to fix the bowden tube problem?
Hey Fred. Indeed these Cubes can be frustrating having gone through all the iterations to get to where we ended up. There is no consensus among users. But the fittings issue lingered regardless.
I've settled on a version of a 'universal cart'. It is based on the early work you are familiar with. However, it settle for using the stock cartridge case with the only purchased item being a 'qualified' bowden tube. And a niche requirement that a bowden tube be 'grooved' to provide an alternate means to hold it in place.
For the printed parts, life is simple; hot end is 3 parts; cartridge is one part; and the bowden tube is 2 parts.
The Cartridge case can be mod'd or left alone. I recommend a generous cutout in the cover for external spooling.
Two means of make a 'grooving tool' are also covered. However, this is where I loose interest from most. I have a simple way to do it on a lathe but it is certainly not the only way.
The system requires some maintenance in cleaning the nozzle from time to time.
I would love to have the time and space to do an 'instructable' on this just to explain the various elements if nothing else. It really is a simple process with real advantages.
Attachment 13345
Attachment 13346
Attachment 13347
...now back to the subject at hand. I am sure other printers could be adapted to use a similar technique. Basically this is a captive tube secured by a tube-nut.
Attachment 13348 (early version)