Taz Pro right hotend (extruder 2) not working properly

As far as I can tell, everything seems to be exactly the same between extruder 1 and extruder 2. I can print just fine with extruder 1 (left hotend) but for whatever reason, I always fail spectacularly when trying to print on extruder 2. When loading the filament, the consistency looks identical to extruder 1, but as soon as extruder 2 starts to print, it acts like its not pushing enough flow, as hardly anything comes out of the nozzle and I cant even get a proper first layer. Ive had to completely remove filament from extruder 2 just to make sure my prints on extruder 1 don’t have issues running into uneven print surface from whatever extruder 2 fails to spit out).

I only use all the automatic leveling and measurement features. I have not tried to manually adjust anything because I thought the taz pro has all the fancy stuff to make that automatic, and Im also not very familiar with the process of manually adjusting anything. Any help would be appreciated.

Is the tension set differently via the knobs on the front? The captive nut acts as a tension indicator that’s visible from above.
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The other thing that tends to happen with extruder #2, is it is commonly left without filament in it while you print with #1. It still goes through the heat and purge cycle at the beginning of each print, so any filament in the hot end gets exposed to full power nozzle heat repeatedly. Without filament at the gears to be pushed through during the purge, you will get filament baking to the interior of the nozzle and heatbreak. Then when you do run filament through it, it scrapes the baked residue off the interior and those chunks get stuck at the nozzle.

So, take off and properly clean the nozzle, and unless you change your startup code to not heat it at all, never run it without enough filament that it can purge itself clean.

Additionally, the automatic nozzle offset adjustment stuff gets you in the ballpark, but I’ve never had it get it really right. For the Z, the only way I’ve gotten it truly good was with a mechanic’s dial indicator. You absolutely need to manually adjust if you want it to work well.

(Updated) Correct me if I am wrong but this looks like M175 V2 toolhead just for reference in case anyone had that same experience so to the best of my knowledge to help you & others that’s one of the few things I personally confuse with a h175 which I was corrected about the h175

Consider yourself corrected. There’s one photo and it’s of a Titan Aero’s tension adjustment knob.

The hemera extruder used in the H175 adjusts with a knob on the top, and has no indicator nut. It has a spring perpendicular to the tension arm, not an inline spring like the Aero uses. The Hemera is not used in the pro dual extruder.
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Correct me if I am wrong

There’s some vague resemblance in that they both have knobs and springs, but no, it’s not an M175v2. I would have no reason to use a picture of it when the discussion is about the Pro Dual extruder.

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I only meant the tension set is similar correct me if I’m wrong

Hello. Thank you for the response. For the record, this is indeed in reference to the Taz Pro dual extruder, which is based on the Titan Aero design. LulzBot TAZ Pro Dual Extruder | LulzBot

The tension is the same on both sides, with the nut being more in the middle, though I have tried playing around with tension, with no real luck. I have also completely disassembled this toolhead on both extruders, completely cleaned them out, and from what I can tell, the gear hobb looks brand new. I have also replaced with a brand new nozzle, as well as attempted with the original hardened nozzle, but no luck. For curiosity sake, I even swapped the nozzle from the known working extruder 1, but it still struggles on extruder 2.
Looks like I will have to learn how to properly adjust the z offset, but im afraid of setting it incorrectly and having it crash into the glass bed.

Another thing to check on these, is that the gear on the aerostruder is sometimes not centered properly with the feed tube:
WIN_20231002_14_13_59_Pro

This can reduce the grip on the filament and make it more prone to stripping out.

If your first layer is good, probe Z offset is fine. Don’t adjust it.

Can you do a simple print just a few layers thick, one with extruder #1 and one with extruder #2, and show comparison pictures of the bottom surface?

Kind sir please update your reply

That’s where I got confused