Is the aux part big fan a design flaw or I missed something?

Once again, Bambulab have made an exceptional printer, but as the lack of flowrate for the nozzle I have been surprised from the begining by the big fan design and especially its output shape.

Why the hell is it designed to blow only on half of the bed (the center) ? I mean why they dont use a bigger fan with a larger fan duct that can cover the entire bed ?

I am thinking of making a design for a bigger fan and a fan duct that will cover the whole bed, maybe someone already done this ?

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There is a separate fan for cooling parts. This fan is used to control cabin temps.

The cabin can be heated by the bed (no separate chamber heater on these machine) and that fan might gently circulate to create an even temp for very high temp parts or run fast to cool the chamber for something like low temp PLA.

Get it? :slightly_smiling_face:

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heu nop, this fan is ā€œAuxialiary part fan coolingā€, when I need to print very fast I set my part juts in front of this fan output, it make a huge difference (it is made to always blow at the nozzle height and help colling parts)

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OOPS! Working on that Halo! :upside_down_face:

I see what you mean, it doesnā€™t cover the front of the bed very well.

EDIT: Did you search on Thangs.com? You might find someone did one. Thangs is good because it searches Printables, Thingiverse, etc and gives you one list. You get a bunch of ā€œalso ransā€ but you generally can find what youā€™re looking for.

Yes, thatā€™s it !

I really dont understand why they choosen this design, it is not a problem for small parts as they can be put just next to it, but it could be a problem with bigger parts that have small parts on their corners (note that I always uncheck in filament setting ā€œSlowing printing down for better layer coolingā€ because it is rarely/never needed when printing next to this aux fan and it print a lot faster for small parts)

EDIT: Iā€™ll try Thangs, thanks, I did not know about Thangs until yesterday when Bambulab lauch a new contest on design and mentionned Thangs

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I print mainly with PLA, and for that purpose I even set the Aux fan to 0%. As it is blowing only from one side, I found the tendency to warp the printed parts higher with the Aux fan activited due to non-uniform distribution of colder air flow.

In addition, for higher prints there is a change in the ā€˜coolingā€™ power of the fan as it sucks air from the inside the chamber and at a certain height it changes from far below the bed (beginning of the print) to sucking air above the headed bed.

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Ooof! Iā€™ve been killing it for my PLA but only have my machine 2 weeks so missed that behavior.

I just found Thangs too, pretty neat site.
Cheers!

EDIT: Now I have to figure out how to put it on rails ā€¦ LOL

I would say that blowing from one side should IMHO not cause problem as it blow on the topmost layer, it purpose is to cool the top most layer nothing else I guess, anyway its design is really far from being the best

EDIT: part fan cooling on big parts is not required that much until there are small parts on top of it

I did not yet printed parts enough tall to encounter this issue but it make sense, once again it could be corrected by changing this aux fan design, sucking air somewhere else (from the back or from the bottom)

If it would only that way as you describe (cooling top layer) it would make maybe sense. But testing it (non-sience-way) you can feel that the flow is by far not a straight unidirectial flow but burst appr 20-30% down as well. So this means - depending of the object on the plate and orientation - lower layers down to 3-5mm gets still cooled as well. Take into account that the burst comes only from one side, the model itself acts like a shield as well.

As you mentioned, bigger parts donā€™t need the Aux fan for cooling as they stay above the max threshold time set. But as it is currently implemented in the slicer you can only choose to have it on (with a set amount) or off. But this is maybe something that can be fixed more easily (similar setup like like the standard fan with tresholds)

There is certainly enough room to at least run another fan on the other side of the print chamber

Having the cooling on both sides would eliminate at least one direction when we need to orientate the print for better cooling

I just donā€™t know if thereā€™s enough room to run a duct that wraps around the interior

Iā€™ll be following this thread with great anticipation because your thoughts are right on par with mine regarding the Aux fan

It looks like there is space for an identical aux fan on the right side of the machine. Iā€™m curious if dual aux fans were part of the original design and were cut for cost reasons. I think Iā€™d prefer to have the aux fan on the right side to help supplement the part cooling fan, which only blows from the left. So far I havenā€™t had much need for the one aux fan, let alone two, but I do enjoy symmetry.

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I think there is actually quite a few provisions available for future expansion

Also since Bambu spent a substantial amount of $$$ on the tooling for manufacturing their printers it only makes sense that the X2 and X3 series of printers will make use of these extra spaces and bolt holes

I do wish that a manufacturer would implement a dual print head design with enough room for the idle head to completely move out of the build area so as not to reduce the build volume but Iā€™m simply a consumer and not an engineer or marketing advisor

I guess as always time will tell and in my opinion these printers are still so fresh that the printers we have are still somewhat of a beta version which is actually a good thing because it leaves plenty of room for advancement in the future

Something tells me the next generation will also have a larger build volume which would be great

Iā€™ve been thinking an X1C XL or X2D XL is at least in the heads of the BL team. D= Dual. XL = 300 or 350. Itā€™s a natural progression.

Edit - Also meant to say They were selling the Aux fan for P1P people , canā€™t see why you couldnā€™t slap one in.
Personally, Iā€™d power it individually, no idea if the system could handle the additional load, be a b*tch to blow a motherboard ā€¦ :open_mouth:

Sorry but thatā€™s incorrect. Youā€™re thinking of the chamber fan.

YouTube channel 247 printing has a Voron v0 printing super fast, like a 3 minute benchieā€¦ he basically has two aux part cooling dans, one on each side. Iā€™m sure someone in the community will figure out how to add a second aux fan which would help with lack of cooling for fast PLA on the right side of the printer.

I think he is correct by stating the aux fan: Auxiliary Part Cooling Fan | Bambu Lab EU

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ThanksForAsking said ā€œthis fanā€ is used to control cabin temps. The Aux fan cools parts.

I think it would be a good idea to pul the air from the outside for us with x1c and PLA printing to keep the chamber cool

This would be the best case I guess, unfortunately I got a X1 Carbon and donā€™t wanna make an hole in it :slight_smile:

Thereā€™s an interesting piece of info in an odd place - The SALES page of the various print plates has a chart with recommended print info.
Like here for the Cool Plate: https://us.store.bambulab.com/products/bambu-cool-plate-combo ā† You need to scroll down on the page a bit.

Iā€™ve linked this in the past and it used to say to have the door open and the top glass removed for PLA. It seems they revised it recently.

Interesting.

IMHO the terminology used by Bambu for the various fans seems to have been ā€¦ ummm ā€¦ not as carefully chosen as they might have intended.

This is not the first thread Iā€™ve see where the parties involved get confused as to which fan is being discussed, myself included! :innocent: :grin:

To quote oneself seems a bit odd ā€¦

I was taking about the ā€œAuxiliary Parts Cooling Fanā€ seen in the second photo in the Manual under Cooling system Introduction to X1/X1-Carbon | Bambu Lab Wiki