Really bad quality prints after fixing bowden tube

Filament 3D Printer Technical Help Creality Ender 3 / 3 Pro / V2
#1

Hi guys,

I’m using an eneder 3 stock everything, never felt the need to upgrade. Recently I watched the chep video where he discusses basic maintenance on an ender 3. He showed how thw bowden tube shpuld be removed and checked, and if there’s gunk at the bottom just snip off the bottom then stick back in the hot end.

So I did what he recommended with the bowden tube, I had never checked it before so it was in bad shape, quite a bit of gunk. So I cut off that bit and put the tube back in. While I was at it I also replaced my nozzle with a brand new 0.4mm nozzle. I ran a stringing test print and it turned out beautifully.

Ever since then I’m getting absolutely terrible quality prints, there’s like weird burnt plastic blobs appearing across the print, the extrusion seems funky, and it overall seems to be stringing and breaking apart in ways I’ve never seen before. I think I’m going to replace the nozzle as a first step but I’m wondering if anyone knows anything else that I can do to fix this.

Also sidenote I noticed that my nozzle sits kind of crooked from the heating block, although it seems like the nozzle is straight but the block is crooked. Is this normal?

20210224_081755
20210224_0817551908×4032 1.07 MB
20210224_081802
20210224_0818021908×4032 1.11 MB
20210224_081742
20210224_0817421908×4032 1.35 MB

#2

When you cut Bowden Tube, did you use a razor blade or Tubing cutter?
The cut also MUST be perpendicular to tube , if Not Plastic will Squeeze out and fill that gap, causes Zits and burnt globs.

I’ve seen people cut it with Side cutters, WOW the mess that makes!!

When you install Bowden tube back in the top you need to pre load it too.

You loosen the threads on Air line fitting one whole thread.
Push Tube in all the way,
Lift Latch on Fitting,
Install blue lock clip,
Tighten the Fitting threads down till firm tight.
This will Press the Bowden tube into the nozzle, and make a great seal.

It looks Like Metal shroud is crooked, not nozzle
those 2x M3 Button head caps screws will fix that.
2mm Allen Key*

#3

Okay I think I’ve created a new problem now… no matter how much I tighten the nozzle, it never gets tight. Maybe I stripped it? I’m guessing there’s no saving that :frowning:

#4

This sounds like the beginnings of an issue. As Keith pointed out eveythings needs to be in very good contact, if something is misaligned it is not awesome. Heat blocks especially aluminium can be stripped or cross threaded easily. It sounds like the block is toast. Personally these parts Nozzle, block, and heat break I consider wear parts. I replace them if there seems to be too many issues. They are readily avaliable I tend to like the brass heat blocks (usually plated) they are heavy and might be slower to heat up but also cool off. They are harder than the other common metals used in heat blocks, harder not hard like steel.

#5

To save myself any more headaches I decided to buy a new hotend assembly from 3D printing Canada. I don’t think what I have is salvageable anymore unfortunately.

#6

This is helpful to me as I was having trouble with the bowden tube being pushed out as the filament advanced. I finally got it to stay but I wondered about where the ridge on the bowden tube needs to be when it’s assembled correctly.

1 Like
#7

I’m glad someone benefitted from my screw up! :sweat_smile:

#8

No Worries Miranda, We were all in Learn Phase Some time in our lives.

Heck! Some People think of me as a Pro, I tell them nope, I’m Still in Learning phase!!

Always willing to learn more!