Does everyone end up with the PTFE tube problem?  

RE: Does everyone end up with the PTFE tube problem?

Hi to reassure you I have my Mini since May 2020 since then I print more than 3 spools of PLA and almost all my print were successful. I think on forums you see the negative minority. The only "problem" that I had was because of the pinda I have just upragded to the SuperPinda and now it's a perfect little printer ! 

RE: Does everyone end up with the PTFE tube problem?

Im interested in this as well - family member is getting a mini+ and Ill definitely examine the hotend.

Today a person gave me a nice solution for that PTFE problem - just put inside a small 1mm PTFE on top of the hotend PTFE so it wont be too short even after shrinking.

RE: Does everyone end up with the PTFE tube problem?

I had PTFE end melted after few months of printing PETG (mostly Prusament, 240-250 degrees). So, eventually, the problem may appear. I replaced it with piece of Capricorn tubing which is stiffer and has higher temperature resistance, I'll see how it goes. Other option is to separate hot zone by different heatbreak with an actual ... heat breaking throat 🙂 like Bondtech, but some people here reported problem with this as well. Stronger cooling (replacing heatsink fan) helps too, make sure it is working properly and not stuck or obstructed too much.

RE: Does everyone end up with the PTFE tube problem?

Hi Raymate,

My Mini worked perfectly at first. Print after print came out wonderfully well. Then I had a big snarl up, after 6-8 weeks. After a big sort out, including changing the PTFE tube to use the included spare and sliding up the hot end, all described in this forum, the Mini has been reliable and accurate ever since. Some folks do seem to have a struggle but as mentioned above many just keep on going. I’d happily buy another. 

RE: Does everyone end up with the PTFE tube problem?

@3dk

Sounds like I should still get it and leave mine on order. So it seems I should check the screws upon arrival and hope for the best. 

It also sounds like you get a spare tube in the box anyway so thats something I wouldn't have much down time if I need to replace it.

RE: Does everyone end up with the PTFE tube problem?

Seems like early versions and some not specifically for that part quality checked ones have problem with it. Around April 2020, the problem started to be public with the inner tubes, so I assume, Prusa made double checks for some time until they made automated tube cuts (or something automated). From my side, as I see it (deliv. : 6/2020),  some filaments are not good and cause problems. Like for half a year, I had no issue with printing, so no cold pullouts and no taking apart anything there, basically nothing was unscrewed there. Then I tried some different PLA* vendors and PLA* types (glow, recycled, too cheap, ...)  and started to have issues.

Olof who made the Bondtech extruder told me (chat on facebook), that stifther/tougher filaments, like usual PETG* will have no issues. But soft ones like most PLAs* and mixtures will have. I had no issue with PETG*, but except for 2 PLAs* , all others (6*) were doing some problems (high temp, break, grinding).

* Except for the samples with printer, I have not used any filaments from Prusa.

RE: Does everyone end up with the PTFE tube problem?

I have only printed PLA yet and have not run in any problems of this sort. Overally my mini worked well from the start (got it end of october 2020), don't even have problem with the pinda. I agree that quality control should ensure correct length of the tube by now. On the other hand I don't think anyone willing to 3d print should be scared of changing a little tube.

RE: Does everyone end up with the PTFE tube problem?

Posted by: @raymate

@3dk

Sounds like I should still get it and leave mine on order. So it seems I should check the screws upon arrival and hope for the best. 

It also sounds like you get a spare tube in the box anyway so thats something I wouldn't have much down time if I need to replace it.

 

There's a spare, yes, and if you order something from Prusa e-shop like filament or spare parts, you can throw in few pieces of replacement tube too. But PTFE tubing is considerably cheap, buy few meters/feet of it and cut it to length - here are some nice jigs you can print, they help cutting to proper length and chamfer edge to the right angle. https://www.prusaprinters.org/prints/3644-ptfe-tube-chamfer-and-cut-jig Blue Capricorn is pretty expensive though, but you do not need a lot of it. You just cannot chamfer it with utility knife, I filed it with nail file instead.

RE: Does everyone end up with the PTFE tube problem?

I face it once, work perfect after change ptfe, when problem occurred filament stop came out after 30 mins print. Try cool pull, clean extuder etc. But change ptfe make it solved. I have any problem contact prusa, they always welcome to ask. 🙂 Good luck

RE: Does everyone end up with the PTFE tube problem?

Think I will print out that jig cutter ready and buy some PTFE tube. 

Any specific tube or will any PTFE tube do. I keep seeing Capricorn is that OK to use ?

RE: Does everyone end up with the PTFE tube problem?

@raymate

You can use spare part(they give you 1) and in prusa web, they suggest use pen sharpener to cut the tube in shape.
I bought PTFE tube from the shop that i bought, I do not know what kind is ptfe that they gave me. good luck

RE: Does everyone end up with the PTFE tube problem?

I have 4 Minis and the oldest is over a year old.  I have had NO PTFE problems in 12 months.  

RE: Does everyone end up with the PTFE tube problem?

My mini is about 6 months old and I've replaced the PTFE twice.

Once with the spare in the kit and then I cut my own from a piece of capricorn tubing I got from Amazon. No problems since but I wouldn't say I'm a heavy user. I didn't even cut it that accurately (not to Prusa's spec anyhow) and it still works fine.

I wouldn't let it put you off getting a mini, it's great printer.

Just order some PTFE tube beforehand, in my opinion it's a consumable and everyone will need to replace at some point (even cwbullet 😉 )

RE: Does everyone end up with the PTFE tube problem?

@leem

That is odd.  I run my minis 12-16 hours a day.  I am still using my original PFTE.  I even print ABS and PC Blend.  

RE: Does everyone end up with the PTFE tube problem?

As i know there is some batch that have this problem, later batch ship with no problem.
I suggest look at this one

RE: Does everyone end up with the PTFE tube problem?

I have the Mini + with the injection moulded bits. I’ve had it a few weeks. To begin with it was fine. But now I believe I have the PTFE tube problem. 

I have consistent under extrusion and have wasted many hours doing cold pulls, resetting the bed sensor height, cleaning out the nozzle, but the only way I can get filament to stick with way too much smoosh on the first layer, which causes blockages later on in prints. It is super frustrating, nothing seems to make a difference. 

I’m on with support now to resolve, but I’ll say this: If like me, you are buying this printer because it’s a ‘it just works printer’ then don’t. It isn’t. I had a Creality CR4 previously and got fed up with the manually bed levelling and the inconsistency in the glass bed. But I’d actually go back to it now. I never had any issues with clogging or under extrusion in lots of hours of printing with the Creality. I never had to take the hot end apart or do cold pulls. 

For the money, I’d pass. 

RE: Does everyone end up with the PTFE tube problem?

@bodgers

Think I need to stop reading the forums 🙁 its making want to cancel my order.. I want almost plug and play. I know it will need maintenance but its sounding like it will need surgery every now and then... wish Prusa would acknowledge our concerns and either fix it or re assure us they know something is up and working on it.

RE: Does everyone end up with the PTFE tube problem?

@raymate

Don't let it discourage you.  

RE: Does everyone end up with the PTFE tube problem?

Like @cwbullet I have printed 16 hours a day for months at a time, with high temperature filament, mostly PETG but some ASA. I have not had to replace the PTFE tube.

There is no "plug and play" 3D printer. To get good results, you have to recognize anomolies in each print and figure out how to best eliminate them. Each object and each filament has it's own settings. With this knowledge and experience, I have very few failures, maybe 10 out of hundreds of prints. I do cold pulls after switching to a lower temperature filament from a higher temperature one. I've figured out optimal adjustments of head parking, MINDA warmup, bed treatment and extruder settings. In general now, I just start it up and print successfully. I dry all my filament and may suggest that wet filament may contribute to a variety of ills not recognized as such. If the area of the PTFE tube gets hot enough to boil water, the expansion might damage the PTFE tube. I really don't know if that is true.

Regards,

Mark