Multiple printing issues, considering rebuilding extruder  

RE: Multiple printing issues, considering rebuilding extruder

Use live chat from the store, not email. You'll get a direct chat with someone.

Unfortunately, it sounds like you've just been throwing parts (and money) at the problem without really knowing the issue. That always leads to frustration and disappointment. 

So - try live chat as suggested, or post a detailed description of your issue here (with pictures) and the community will try to help out. 

RE: Multiple printing issues, considering rebuilding extruder

As Vintage said: log in to the Prusa store: use the CHAT function shown here.

My main issue is that the prints are not consistent and I can't figure out why after trying everything I can find 

Would you care to say what inconsistencies you are having?   Maybe someone here has an idea.  Often the cause for something is not as obvious as it seems.  And many problems share symptoms, but not causes.

ps: photos are a huge help in diagnosing issues. Just be sure to use the LINK TO : MEDIA FILE option before pressing INSERT.

RE: Multiple printing issues, considering rebuilding extruder

Posted by: othman.a2

Hello everyone,

I hope that not everyone is as frustrated as I am with their MK3S. I definitely regert the purchase but at this stage I'm stuck with it so I have to make it work somehow despite customer support not even bothering to reply to emails.

My main issue is that the prints are not consistent and I can't figure out why after trying everything I can find on this forum, Youtube, Prusa blog .. etc. Changed nozzle, filament, heat-end, teflon tube, .... no luck.

I am considering throwing away the extruder that came with the printer, buying all the prats again and re-building it. However, given that this is expensive and I have little faith in Prusa products - would it be possilbe to build an extruder from a different source that is more reliable? Has anyone tried this?

Thanks!

 

 

Hi 

I just bught the upgrade too, (MK3S) and i had a lot of inconsistant prints too. in the same prosess i upgraded the firmware to 3.7.2

I tried everything!! calibrating everything !! nothing helped !   So, finaly i downgraded the firmware to MK3S 3.7.1  and now its printing like a dream again.   

( issues were: undrextrution, nozzle temp. not correct (hat to crank it up to 280 degrees for PETG), )

hope this helps 

RE: Multiple printing issues, considering rebuilding extruder

Posted by: christian.s13

 

hope this helps 

It won't. You're throwing anecdotal evidence at a vague description of the problem that may or (probably may not) have the same underlying cause. While I appreciate your desire to be helpful, without the OP actually describing his issues and providing pictures, guessing at his problems and trying random things to fix it is more likely to just complicate matters. It's just the time-equivalent of throwing parts at the problem and hoping it fixes things.

RE: Multiple printing issues, considering rebuilding extruder

hey , maybe English is not his first language, and he doesn´t know how to explain it. but flashing firmware 3.7.1 can in no way make anything worse. 

RE: Multiple printing issues, considering rebuilding extruder

Posted by: christian.s13

hey , maybe English is not his first language, and he doesn´t know how to explain it. but flashing firmware 3.7.1 can in no way make anything worse. 

Actually, if something is broken, flashing new firmware CAN make it worse because now you have new firmware working on old cal constants that weren't removed during the flash operation. And it is common knowledge with flashing firmware new problems are almost assured unless a full factory reset and careful full calibration is done.

It's analogous to Q: "My car stopped and engine light came on! What do I do?"  A: "Change yer oil, hope it helps." 

RE: Multiple printing issues, considering rebuilding extruder

Brand new forum member with a grand total of 1 post about a problem he doesn't describe so cannot be helped.

I wouldn't get too worked up. Most common scenario is the OP won't even come back to the forum. Until someone returns or has multiple posts, there is very little gain in putting in any effort to help. That's just the nature of forums. You eventually burn out those who spend time writing long, helpful posts that a new OP either ignores or never comes back to see.

I would wait and see if the OP comes back with more info before expending any more effort in this thread.

RE: Multiple printing issues, considering rebuilding extruder

Hello again,

Thanks for everyone's responses and I'm sorry it's taken me this long to get back here. It's been a busy week.

Let's start with images, taken over several weeks (not sure why they're streched - click to view in correct aspect ratio):

1. Spaghetti monster et al:

2. 2. Random blob on support layer:

3. Poor first layer + under-extrusion:

4. Layer shifting?

5. More of the same:

6. More...

7. More spaghetti + stopped extruding mid-print:

----------------

Of course, I've shared all for these and more with the support team and I understand that it's a guessing game since all they can go by is my word and photos which is probably not enough to solve all issues.

Over the past four months I've tried (what I remember at the moment, not ordered):

1. Cleaning the bed with IPA and running first layer calibration.

2. Re-wiring, all-data reset, update firmware.

3. Cold pull.

4. Clean and grease extruder gears.

5. Clean and grease xyz shafts and bearings.

6. Check axes belts and made sure that the pullies are properly aligned.

7. Adjusted extruder tension bolt.

8. Heat nozzle to 285 for several minutes and pushed 20 cm of filament through it.

9. Changed heat break to prevent stuck filament.

.... pretty sure there's more but this is what I remember now.

From time to time I get lucky and manage to print one or two small-medium objects before we get back to square one. However, I haven't been able to successfully print a single object for the past 6 weeks - not even the Prusa models that came with the printer.

Anyway, today I had a bit of time after work so I took apart the hot end and found this:

Clearly, there's a leak but from the size of it, it doesn't explain 4 months of sever under-extrusion - does it?

I cleaned everything but while trying to put it back together I managed to damage the heat break thread (oops). While ordering a new heat break I decided to also get a nozzle, heatsink, and heater block becuase at this stage why not?

I'm curious, how often do you guys have to troubleshoot/maintain your printers? How many prints can you do before having to troubleshoot?

If the amount of troubleshooting/maintanace I've had to do is normal, it kind of makes the money savings not worth it. I would've been happy to pay extra and save my time for productive activities.

Thanks again and have a great weekend 🙂

RE: Multiple printing issues, considering rebuilding extruder

Hi Othman, 

the amount of leakage we can see in your pictures is probably  not enough to cause the problems that you are having. 

be very careful removing the heater and thermistor, the wires are a bit delicate... 

here is a link to changing the PTFE Tube,   make sure that the PTFE is unable to move up and down after you re fit it. failure to do this step correctly will lead to a whole load of pain later!

https://manual.prusa3d.com/Guide/How+to+change+a+PTFE+tube+-+Original+Prusa+i3+MK3-MK2.5/761
when you rebuild,  reset live Z to 0.00 (Settings menu) then go back to the build manual and start from  checking the Pinda height with a zip tie, as the newly rebuilt extruder is likely to be marginally different in length to the old set up. 

I use the Life adjust Z My way, files to set my Live Z  value, for me, it's much better than peering at a single thread and vondering how squished it is... 
then try some of the pre sliced files, such as Buddy, Benchy, the whistle   and see how the printer runs with the new parts. 
Goodluck,
Joan

RE: Multiple printing issues, considering rebuilding extruder

^^ Do post pictures of your live z squares when you get to that point. From your pictures it's clear your first layer was way too thick (Z not negative enough). 

This is the thread Joan was referring to:

https://shop.prusa3d.com/forum/assembly-and-first-prints-troubleshooting-f62/life-adjust-z-my-way-t2981.html

I'm curious, how often do you guys have to troubleshoot/maintain your printers? How many prints can you do before having to troubleshoot?

For me it's nearly always been print and forget. The only issue I had at one point was a loose PTFE and an idler shaft that worked its way loose from the door. (I did have some bunk bearings/rods, but I caught that before it interfered with printing so I didn't have to troubleshoot it - and I could easily have continued printing for a while longer without negative effects) I've modded some other aspects of the printer but the core has always been reliable for me. I've probably clocked around 6-8kg of filament through it since I started printing in early Jan. (judging by empty spools and what's left on the ones currently out). I think in your case you've hit a rather rough bump in the road, but it's definitely not the normal experience. We have many knowledgeable forum members and we'll do what we can to get you sorted and enjoying the hobby as much as we do.

RE: Multiple printing issues, considering rebuilding extruder

My only comment would be - don't rush anything.

Get it assembled to your satisfaction, and tune in Live Z.

Post your result here and get some feedback before plowing ahead.

After Z is dialed in, next step might be the GCode Benchy.

Again, post your result and get some feedback.

You have already been at this weeks - might as well take a couple of days to check the basics.

RE: Multiple printing issues, considering rebuilding extruder

The leak out of the hot end means you didn't follow the E3D-V6 or even the Prusa guide for working on the hot end.  So you've created a lot of problems and hours of extra work for yourself - all because you didn't spend 5 minutes reading the how to guide.  Seriously, reading the manual is not only a good idea - it is required.  Read the assembly guides before doing anything else -- and there are no shortcuts -- skip any part of the guide and guess what?  The nozzle will leak or not perform as designed and give you prints that are, well, just like the ones you are showing.

https://wiki.e3d-online.com/E3D-v6_Assembly

In the time I've owned my MK3, I've worn out bearings, worn out a few nozzles, cleaned and regreased it a few times, that's about it.  Oh - I did replace the Prusa heat break with a stock E3D-V6 version because I don't have plans to use the MMU.

RE: Multiple printing issues, considering rebuilding extruder

And your images are stretched out of proportion because you didn't use the medium thumbnail size. Large distorts the images; but with LINK TO : MEDIA FILE set, people can click to zoom to the full size. So thumbnail or medium images is best.

RE: Multiple printing issues, considering rebuilding extruder

and clean your flex sheets with dish detergent ( plain Dawn) and lots of running water

RE: Multiple printing issues, considering rebuilding extruder

Add I tried to find the random blob on that image: I don't see anything but the abort string. All of the other bits almost look normal.  But most blobs come from a leaky hot end.

And you really need to avoid touching the print surface: fingerprints will kill print jobs as much as a broken hot end.  This is why David is suggesting you wash the sheet. Alcohol wipes just don't have the volume needed to rinse the oils off.

RE: Multiple printing issues, considering rebuilding extruder

like  i said , try flashing 3.7.1    i had the same issues.. 

RE: Multiple printing issues, considering rebuilding extruder

Posted by: christian.s13

like  i said , try flashing 3.7.1    i had the same issues.. 

Please stop suggesting software to fix hardware issues.

RE: Multiple printing issues, considering rebuilding extruder

here is my " hardware issues" .. please stop correcting me, i did absolutly nothing other than flashing 3.7.1 . . just because, i just started posting in here doesn´t mean that im new to 3d printing. 

what you see on my pictures happned after i flashed 3.7.2. AND it was corrected again when i flashed 3.7.1

ANYWAY that is all from me, not gonna post again in here 🤔 

RE: Multiple printing issues, considering rebuilding extruder

Posted by: christian.s13

here is my " hardware issues" .. please stop correcting me, i did absolutly nothing other than flashing 3.7.1 . . just because, i just started posting in here doesn´t mean that im new to 3d printing. 

what you see on my pictures happned after i flashed 3.7.2. AND it was corrected again when i flashed 3.7.1

 

ANYWAY that is all from me, not gonna post again in here 🤔 

I'm not refuting it fixed *your* problem in *your* case. But the OP has posted images that clearly show, at minimum, an extruder assembly issue, bead cleanliness, and first layer Z issues. No amount of software changes can fix that. So yes, I *will* continue to correct you (or anyone else, regardless of how long they've been around) if they post misinformation.