Is the left nozzle the same as the ones I already have for the H2S? I assume so, just confirming.
When the right side is swapping, Im assuming it’s cutting the filament. Is the break in the filament causing any imperfection/deformity in the print when the nozzle swaps back and continues with that color/material?
If there is no poop or sharing of a nozzle whats the reason to have a purge tower? Wouldn’t the nozzle just pick up where it left off with the filament thats already in it? I realize if your colors/materials exceed the number of nozzles there will be a purge/poop… so is the tower only for those situations?
It looks like the right nozzles can vary in size so Im guessing models can now be printed in variable nozzle sizes. Does that also mean the left nozzle can be any size as well or must it be 0.4?
Yes, Identical standard hotends on the left nozzle.
I haven’t seen any issues with this, but I also use a “prime tower”, don’t confuse it with “purge/poop”. The prime tower is important for limiting imperfections when the nozzle is swapped.
When a nozzle stops printing for a while, the filament at the tip cools, shrinks, and can trap tiny pockets of air. When the nozzle heats back up, that first bit of material can:
• sputter
• bubble
• under‑extrude
• leave rough spots on the model
The prime tower provides the printer a path around that unstable section, so the model only sees a clean, steady flow.
Yes, they can vary in size. No, you can’t use multi-size nozzles in a single print. Bambu’s language about this does not promise it will come but hints at it: “The firmware supports mixed flow‑rate printing (standard flow + high flow), but does not yet support mixing different nozzle sizes during printing. If this feature is added in the future, we will provide details through a software update.” | “Can H2C dual‑nozzle printing be used with different nozzle sizes simultaneously? Not currently. The firmware does not yet support mixing nozzle sizes (left vs. right or within Vortek hotend sets).”
Just to add to this very good answer that this semi purge and prime of old material is done on all changing systems including tool changers and the upcoming indx. All can do without a prime tower if forced with well side effects and all can be tuned in how much is done in this step. The h2c has 2 settings now one that is very conservative and even work on bad/wet material one that works fine but assume that you feed in nice and dry filament. We can kind of say the same about the ‘starting’ poop the h2c does clean the nozzles it will use at the start of the print and does it very conservative compared to the others. In general the whole h2c is very conservative at the moment with many checks and ‘cleanup’ on every start of a printing job. After about 400hours now i kind of agree with bambu on this but it would be nice to have some more options like for example ‘draft’ mode that would only do a full startup path first time you turn the printer on for the day and sidestep many steps.
Im a little confused with number 2 though… If the prime tower is going to use the cut piece of the filament and then continue with the print using the new filament from the roll then how is that any different from having a single nozzle that would purge that cut piece and continue with the new filament (whatever color/material that may be).
Unless there’s some purge differences when calibrating in a different color/material on a single nozzle (H2S/H2D) versus calibrating for a nozzle swap on an H2S using the same filament that was already used by that nozzle… if that makes sense.
In a single-nozzle setup (like AMS color changes), the nozzle is still full of the old color when it switches, so it has to purge until only the new color is coming out. That’s why you see poop and a purge tower: it’s literally flushing mixed material out of the nozzle. With a dual-nozzle swap, it’s different because each nozzle already has the correct filament loaded, so you don’t need to completely purge an old color out before continuing. The reason for a prime tower is just to make the first extrusion after a nozzle has been sitting idle clean and consistent (pressure rebuild, tiny ooze, etc.) before it touches the model again. In short: purge = get the old color out, prime = get the nozzle flowing nicely again.
Yes I understand this, but maybe I was confused or misunderstood your initial response regarding the break in the filament during a nozzle swap.
I took your response to say that you dont have issues with the break contributing to defects or marks in your prints because you purge the cut piece so the break isnt incorporated into the print. As far as I understand that is what is purged as poop in a single nozzle system to get to the new color/material to get calibrated in the nozzle. If that is the same piece youre purging during a nozzle swap in an H2C to get back to a solid unbroken filament then I didnt see how there is a reduction in the amount “wasted”. Unless in a single nozzle system the further purge of the new filament contributes to waste that the H2C wouldnt because it doesnt purge any or as much of the solid portion of the filament once its in the nozzle. Thats what I was trying to understand.
Gotcha, I’ve never seen any flaws related to the cut. I imagine this is because it is upstream of the melt zone in the nozzle, once melted and pressurized it turns into a continuous stream. Any small artifact you might see after a swap is almost always from the restart itself (pressure not fully rebuilt, tiny ooze, slight under-extrusion for a moment), which is exactly what the prime tower is meant to absorb before the nozzle touches the model.
Thanks, I wasnt sure if it being melted eliminated any issue although logically it should. I appreciate your time, youve helped me decide to purchase the vortek upgrade kit once its available for the H2S.