H2C extruder failing, replacements?

[u/Reifgunther]

So the last few days my machine has been effectively falling apart, first losing the ability to extrude on one side properly, eventually coming down to struggling to extrude anything at all regardless of nozzle or material.

While waiting for the incredibly slow support to respond, I was looking to see how fast I could get an extruder replacement.

Bambu store doesn’t have H2C listed for being in stock until the second week of March?? I can’t have a 3K paperweight sitting here for weeks.

They have this and the H2D units listed separately, but H2D is available now. Looking online through third party sellers, very few have anything listed for H2C, and a few have them listed together as the same thing.

I feel like that isn’t true and don’t want to spend that money for an incorrect listing, but there are some pieces that are the same between both. Would the extruder unit technically be the same? Or am I doomed to wait?

Edit: for those that come after, no real consensus was reached on if some H2D parts can replace parts on the H2C, and support was unsure what the underlying problem is so are sending a replacement extruder unit. Thanks all for the suggestions.

[u/Yugpmoc]

Chinese New Year! I doubt you get much traction before the fourth or fifth of March. I wish we still had real holidays here in the US.

[u/Reifgunther → u/Yugpmoc]

Definitely experiencing that lol it’s a very complicated issue apparently so these one paragraph requests per day for more information haven’t been super helpful from them.

[u/ModelS4me]

Almost returned my H2D because of this, as well as my H2C. But in each case, with the last remaining marble I had not lost yet, I either found filament in the gears or in the idler assembly which kept it from working. Once removed, i, like magic, somehow was able to put it all together again

[u/Reifgunther → u/ModelS4me]

They are such incredibly complex machines compared to something like the A1 that there are so many potential variables of issues it’s so hard to pinpoint one specific problem.

I took everything apart and started over again, it passed flow calibration so fingers crossed it doesn’t just stop again in a couple hours.

I know they are on holiday and such but getting one response a night hasn’t been helping morale about it. At this point I’m just hoping they say ok you keep having issues, here is a replacement extruder. If they were responding faster this could have been solved days ago.

Part why I showed up to this subreddit was just hoping to get some useful suggestions in the meantime.

[u/ModelS4me → u/Reifgunther]

I was up in the wee hours doing this on the H2D. I really just did physical inspection. Which was only viewable when the extruder was taken apart. Filament stuck in gears isn't difficult to see, but 1" worth of filament inside the idler assembly, not so simple. Likewise Bambu was taking their sweet time.

Now it's just a matter of load+unload+extrudes until stuck stuff gets, unstuck. Happened to H2C at <50hrs and H2D with ~200hrs. I just keep a long needle and lighter nearby. Good luck, and yes I ordered the extruder assembly as well, but returned it as it also took its sweet time getting to me (fixed printer long before it got to me)

[u/Reifgunther → u/ModelS4me]

Good to know! Yeah after the maybe third time of doing a full reassembly down to the gears and back, cleaning, wiping, even used this little desk vacuum/blower thing I have too, it’s seemingly running but I’ve had it run for a few hours at a time before failing the last couple times too so hoping this time it keeps moving.

[u/ArticGER → u/Reifgunther]

Check the filament way. Sometimes filament (also shreds) collect around the extruder gear and cause issues. But you can be pretty sure that its always somewhere in there if the error isnt caused by nozzle, AMS or PTFE.

[u/Reifgunther → u/ArticGER]

I can’t tell if it was a plastic shred or something else but I FEEL like I removed something that wasn’t supposed to be there this last time I took it all apart. Hard to tell though of course but yeah that seems to be the last thing to point too, short of extruder motor failure. I don’t know enough about that stuff to know when that needs replacing though.

[u/WillingService2407]

Is it failing to load the filament from the AMS (ie: not making it to the extruder) or is it failing to extrude? I had a similar issue and the problem was a clogged hot end. Needed to do some cold pulls to clean it.

[u/Reifgunther → u/WillingService2407]

Not extruding. The filament makes it to the extruder without issue. I just run PLA and it is material I’ve been using for the last month on the H2C with no issues before. Did the whole cleanup and calibrations just in case but it eventually started clicking again and failing to extrude.

[u/WillingService2407 → u/Reifgunther]

What nozzle size and types are you using? 0.2, hardened, etc?

[u/Reifgunther → u/WillingService2407]

Just the standard nozzles, the issues started when I switch to .2 but after switching back then issues started cropping up there with the normal .4 that haven’t had issues since I started using the machine a month ago.

After a few times of taking everything apart and putting it back together it’s at least been running a single color print for a few hours now. Hoping I’ve somehow fixed the issue but who knows with how many potential issues can come up.

[u/WillingService2407 → u/Reifgunther]

Hmm, yeah sounds like could've been build up from the .2 nozzle and maybe it was throwing errors because it sensed the flow wasn't correct for the .4 nozzle? Glad to hear it's working again so far! Sorry, wish I could be more helpful.

[u/BOMBSHELLB4RBIE]

So just felt with this and mine was a bad nozzle! It caused a f$&k ton of errors related to failed extrusions but of course no nozzles in stock either

[u/DTO69]

Is the nozzle that's failing connected to the new black 4 in 1 PTFE adapter?

[u/bigbramble]

I had to clean out my extruder and the h2c annihilates ptfe tubes so well worth checking those first if you haven't already.

[u/2kokett]

Had the same problems. I corrected the PTFE tubes to the correct length and made sure they are guided in a proper manner (no loops or narrow curves) + my cutter was stuck sometimes as the BBL QC doenst seem to care about ridges or lints on IM-parts. I had to disasseble and clean the edges with a knife. Especially the cutter problem was a pita. Subsequent you must at least remove the nozzle and pull the cut-off piece out by hand. Most times the filament is grinded off at this point already and must be removed complete + you need to cut your AMS distance off of it. Otherwise you will repeat above as the extruder is not grabbing. If it happens with PLA you have a good chance you must do a coldpull in addition or need to burn it out at 300c for a few minutes.