Filament jams in heatbreak.  

Re: Filament jams in heatbreak.

There is a larger id bore, on the microswiss, on the hot side.

Not according to the cross-section shown on the link that you posted, it shows the larger id bore on the cold side. Is the drawing incorrect?

Re: Filament jams in heatbreak.

Hey Sean,

Any chance of you printing another single wall cube with this new heatbreak? Just curious if this has any relation to our inconsistent extrusion issue (i.e., small amount of friction/backpressure that consistently hits a "breakover" point and gives us the random yet consistent blobs). I understand this has nothing to do with the moire. 🙂

Thanks!

I am out of state right now, and I haven't done much quality testing. But my current profile, does still have it. I'll be doing tuning this week. Updating Slic3r ate my profiles, which needed updating anyway, so I'm restarting from scratch when I get home. (I know I could likely restore it somehow, wanna start from scratch again though)

Re: Filament jams in heatbreak.

I see this same problem. I changed to a titanium e3D heat brake and it helped a little, but I still see jamming with PLA and my single wall cube is full of holes. Not looking forward to ripping the hot end apart again; please let me know if there is additional data in support of the Microswiss heat brake.

Re: Filament jams in heatbreak.

I see this same problem. I changed to a titanium e3D heat brake and it helped a little, but I still see jamming with PLA and my single wall cube is full of holes. Not looking forward to ripping the hot end apart again; please let me know if there is additional data in support of the Microswiss heat brake.

Today I received and installed the Microswiss heatbreak and I'm still having the exact same PLA jamming issues I was having before (sounding very similar to yours, skipping and full of holes where I used to be able to print PLA with no problem). I have also replaced the nozzle with a new e3D nozzle and capricorn bowden tube and still having the same issue. Took my hot end apart 4 times today trying to adjust things like making sure the bowden was cut completely flat, that the top of the bowden was widened adequately, and the nozzle and heatbreak were screwed in as instructed in the e3D assembly guide (1/4 to 1/2 turn of the nozzle loosened and then tightening it while heated last) and my results didn't improve.

It was luckily not a very expensive part to try but for me it did not solve my issues. All 4 prints I've tried since installing it have failed. The head object failed at around 92% (started skipping at around 85% or so from the looks of it) and the phone case started getting holes around the first solid infill layer.

Re: Filament jams in heatbreak.

Those pictures look exactly like what I am getting. I put an extruder turn indicator on the extruder stepper shaft to see if it was skipping and it didn't show any sign of skipping.

I am down to pointing at the hot end heat sink fan being underpowered.

Re: Filament jams in heatbreak.

*****

I am unsure if I have asked you this, but does the temp on the printer change much while printing? I saw a very similar issue, however the topic died, after this idea came up. Total stab in the dark, and it's super easy to check. (watch the display on the printer while it's doing it!)

Re: Filament jams in heatbreak.

The temperature does not change much on mine. I have a silicone sock on the hot end and that helps. I would estimate a change of less than 2 C with cycles in the 30 seconds to 1 minute range. I watch on the printer display and on Octoprint.

Re: Filament jams in heatbreak.

*****

I am unsure if I have asked you this, but does the temp on the printer change much while printing? I saw a very similar issue, however the topic died, after this idea came up. Total stab in the dark, and it's super easy to check. (watch the display on the printer while it's doing it!)

I've very rarely seen the nozzle temperature go down 1 degree from the correct set temperature, but it corrects itself within around 5 seconds . My printer is in the room where I work so I'm able to monitor my prints for the entire duration.

I've also seen the heat bed go 1 degree too high for a few seconds a couple of times when printing ABS but not when printing PLA.

I'm currently trying another print, watching for the past 35 minutes and the nozzle temperature has gone down by 1 degree twice in the past 5 minutes but it's heated itself back up within 5 seconds of the temp dropping.

EDIT: I am trying to print in ABS (my first time printing in ABS since I got the new hotend to replace my old one) and I notice the nozzle temp fluctuates up and down by around 2-3 degrees constantly. I also notice that the print isn't smooth, it seems textured around the edges and only smooth in the center, which is odd. I've had to use heavily modified (from the default Slic3r Prusa ABS settings) print settings to make ABS printing possible, as even with an enclosure I couldn't get anywhere near a viable print until another forum user showed me settings that worked. I print at 270 degrees for the first layers and then 265 for the rest. It's currently set to 265 and constantly jumping around between 264 and 266.

The part I'm printing is a new nozzle fan cover as my default Prusa nozzle fan covers have all drooped on the left to the point of ruining prints after a few weeks so I'm trying some custom designs that were recommended. This may not be relevant but I thought I'd just provide as much info as possible to try to pinpoint problems.

I'm leaving my enclosure door open as I believe having all of that heat sealed inside is what contributed to the heavily warped PTFE tube from my first hotend. I experimented with closing it just now for a few minutes and the temperature still fluctuates constantly.

Re: Filament jams in heatbreak.

For what it's worth, the MicroSwiss heatbreak appears to have fully resolved my clogging issue.

Re: Filament jams in heatbreak.

Which heatbreak is this exactly? The Amazon link on the second page is not valid anymore.

Re: Filament jams in heatbreak.

. I print at 270 degrees for the first layers and then 265 for the rest. It's currently set to 265 and constantly jumping around between 264 and 266.

The part I'm printing is a new nozzle fan cover as my default Prusa nozzle fan covers have all drooped on the left to the point of ruining prints after a few weeks so I'm trying some custom designs that were recommended. This may not be relevant but I thought I'd just provide as much info as possible to try to pinpoint problems.

I'm leaving my enclosure door open as I believe having all of that heat sealed inside is what contributed to the heavily warped PTFE tube from my first hotend. I experimented with closing it just now for a few minutes and the temperature still fluctuates constantly.

270 and 265 are way too hot for abs. 230-250 is really where you want to be. I reprinted the fan shroud in PC and have had no drooping.

Re: Filament jams in heatbreak.

270 and 265 are way too hot for abs. 230-250 is really where you want to be. I reprinted the fan shroud in PC and have had no drooping.

I print ABS at 270.

I also run the cooling fan @ 50% the entire time. Everyone talks about warping, and layer adhesion... Yup. I don't have those issues the way I print.

No fan @ 230-250 yeilds good results regarding drooping, except I keep getting poor layer adhesion. (I have a temp tower I printed from 230 to 280, and I've also printed it with "fan speeds" from 0 to 255, at temps at 230, 250 and 270)

I found optimal quality, and strength, on my NON-ENCLOSED mk3, at 270, with fan at 50%.

Results may vary. I use a geared extruder, and totally different fans.

Re: Filament jams in heatbreak.

270 and 265 are way too hot for abs. 230-250 is really where you want to be. I reprinted the fan shroud in PC and have had no drooping.

I print ABS at 270.

I also run the cooling fan @ 50% the entire time. Everyone talks about warping, and layer adhesion... Yup. I don't have those issues the way I print.

No fan @ 230-250 yeilds good results regarding drooping, except I keep getting poor layer adhesion. (I have a temp tower I printed from 230 to 280, and I've also printed it with "fan speeds" from 0 to 255, at temps at 230, 250 and 270)

I found optimal quality, and strength, on my NON-ENCLOSED mk3, at 270, with fan at 50%.

Results may vary. I use a geared extruder, and totally different fans.

if you are printing at 270 then you should really think about PC it is way way stronger than abs or pet, it does not droop when exposed to the bed or the heater cartridge (look at drooping it is right where the heater cartridge protrudes) it's only weakness is moisture. otherwise it is the juggernaut of filament.

Re: Filament jams in heatbreak.

if you are printing at 270 then you should really think about PC it is way way stronger than abs or pet, it does not droop when exposed to the bed or the heater cartridge (look at drooping it is right where the heater cartridge protrudes) it's only weakness is moisture. otherwise it is the juggernaut of filament.

If I said the thought never crossed my mind... I'd be lying. 🙂

(That's my 70$ Wiha allen wrench set I have on that pic for anyone who cares)

I'm not sure if I will be using much PC though. I have found a supplier of "cheap" (21$/kg delivered 3D870 / HTPLA+ filament)

And I'm planning on getting a extruder later in the year, so that I can extrude 3D870 for sub 15$/kg.

From everything I have read about 3D870 is this.
Ease of finishing like ABS.
Layer adhesion like PETG
Hard like PLA.
Not Brittle like PLA.

Strength tests of other HTPLA+ I've seen, are closer to PC, than "normal" PLA. (which is stronger than ABS and most PETG)

Re: Filament jams in heatbreak.

(That's my 70$ Wiha allen wrench set I have on that pic for anyone who cares)

The internal gearing is so nice! I have the same set - love it.

I bought a few rolls of esun ABS+ and have been having issues with layer adhesion, especially on small perimeters. I've had to crank up the temperature to 270 C as well, and use the fan to keep from warping. I do, however, run a heated enclosure at 60 C.

Re: Filament jams in heatbreak.

I am currently experiencing the exxact same issue's as the original poster.
I have a MK3 that printed perfect for the first month or so, but then started to have the extruder clicking, the missing layers, etc.

I changed to the new housing, but this didn't help. Is there any word if the microswiss option is the way to go now, or is it still up in the air to what the solution is?

Re: Filament jams in heatbreak.

I just want to share my bit about my issues and how I resolved them. For a while, I would either have to leave my enclosure open with the AC running, or I would have to make sure prints didn't run for a long time. Consistently I would have jams at near similar layer heights. For reference, this only occured with PLA. PETG and other materials that heated at a higher melting point did not experience this issues nearly as frequent.

What did I do to fix this? Well I did a few things. To preface this, I read through a lot of forums and tried a lot of work arounds without modding the printer. Then I started by replacing the PFTE tubing, insuring to have the end rounder off as described in the manual. Next, I disabled the filament sensor which unfortunately did not fix my issue as it seemed to fix somes.

What ultimately mitigated my issue was a combination of 2 things. The first thing I noticed was that the filament sensor would get very hot even to the touch. Sure, disabling would have fixed the issue completely, but I wanted the functionality. So I moved the 5v fan that is included in the printer to the top opening (originally mounted with zip ties - I am currently working on a part so this can be removed and reinstalled easier). Secondly, I installed a 12v Noctua fan where the old 5v fan on the left side was. I wired it like so: Direct connection to the 24v rail, which then was installed into a voltage stepper which stepped down the voltage to 12v, and then connected to the fan. This allowed for more air to flow over the "heat sink" (I am calling it a heat sink since the actual name for the tube is escaping me at the moment) which ultimately eliminated the heat creap issue.

Ever since doing these 2 (possibly 3, the PFTE tube might have contributed but I still experienced issues after that alone) simple modifications, I can report that I have had many successful prints that were not working prior. I used the same gcode files and everything, so these 2/3 things definitely helped a lot. Hopefully this will help someone else out, because believe me I was very frustrated with this.

Re: Filament jams in heatbreak.

I have this issue right now, and some filaments are much worse than others. White PLA seems to trigger it and then I basically have to dismantle and replace the slipped out PFTE tube.

Considering the shape of the filament, I'm sure a misaligned heatbreak bore has something to do with it.

(Also I'm quite sure it's a heatsink on top of the heatbreak/throat considering how they look on ebay/amazon...)

Re: Filament jams in heatbreak.

Once you replace the ptfe tube with the proper shapes at each end as described in the Prusa help page be sure to install a lock on the black collet at the top of the heat sink so it can’t work it’s way up over time and block the flow again plenty of designs on thinkverse but be sure to select a small one as there is not a lot of space in the cover below the bondtech gears where it sits for many of the larger ones. Copy the one that e3d sells and includes when you buy a hot end directly from them

Re: Filament jams in heatbreak.

Once you replace the ptfe tube with the proper shapes at each end as described in the Prusa help page be sure to install a lock on the black collet at the top of the heat sink so it can’t work it’s way up over time and block the flow again plenty of designs on thinkverse but be sure to select a small one as there is not a lot of space in the cover below the bondtech gears where it sits for many of the larger ones. Copy the one that e3d sells and includes when you buy a hot end directly from them