TPU to PETG filament change questions

I am trying to print something with my A1, I would like the first several layers to be TPU and the rest PETG, mostly for aesthetics, but also durability.

I know TPU cannot (should not, because TECHNICALLY you can make it work) be used in the AMS lite, so I would start the print manually with the filament on the spool holder, and ideally at the proper level do a filament change via bambu studio after the model has been sliced. i have never done a color change via the slicer like this…or of any kind actually.

I guess my question is, will the printer automatically use the ams based petg filament after printing filament that was used external to the AMS lite?

If I have to manually unload the TPU and manually hang and feed the PETG on the spool holder, will the print pause at that level automatically?
I am mostly concerned that the printer will try to use TPU settings to print PETG, assuming I can even get that far…Or will I have to somehow manually set settings after I change filaments?

I guess, what happens step by step when a filament change is put in via the slicer? Is the filament change via the slicer just for the AMS lite? More or less how do I change from TPU to PETG so the printer uses the correct filament profile to print each filament?

Basically explain this process like I am 5 years old and have no idea what im doing.

Thanks!

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This will work. When you setup a model to have multiple colors or filaments the slicer handles most of the details.

You would select say TPU in filament one slot and that when applied to the part of the model you want would make sure the TPU filament profile is being used when that filament type is in being printed.

Then you select the PETG in filament two slot and apply it to the proper parts of the body and just as above the printer knows, when it switches filament it also must switch a number of parameters for proper printing, bed temp, nozzle temp, flow rates etc…

There is the complexity of one being an AMS filament and the other not, this means manual changes will be required, the printer will prompt you when necessary.

I would finally say to search this on google to find a good overview of someone who made it work well, did they massage some parameters like bed temp or did they just run with the defaults? I don’t know.

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yeah i tried searching this. One source was way more involved than I wanted (involved editing gcode) and the others were older posts with answers that dont really apply anymore due to various updates from Bambu

TPU will not work in the AMS without modification ps that Bambu Lab (BL) doesn’t warranty against.

You will not in the filament guides that TPU is not compatible with the AMS.

If you are hoping to utilise the AMS for this process, you may prefer to wait a couple of weeks as a new product is due to be launched. It is quoted as “flexible material for the AMS”.

Without more details, we can only speculate that this may mean Bambu Slicer (BS) may gain the ability to combine these two materials with ease.

Fingers crossed.

I am not specifically hoping to use the AMS lite for this. I just have never done a multi material print that wasnt petg/pla.

So I dont know how it would work if I have to manually feed both the TPU and the PETG from the spool holder, or if the printer will know the PETG is in the AMS lite and would automatically use that when the time comes.

I know I can either put in a filament change or pause when the model is sliced, i am just not sure what that does. Does the filament change mean from one ams lite filament to another? from an external filament to an ams lite filament? from external to external? The pause, does that just simply stop the print, and then continue what it was doing before it paused? Does it ask if anything changed before things continue? if im printing TPU externally from the spool holder, then pause it, retract the TPU and put in PETG, will the printer know its a different filament, or will it ask me if its a different filament?

These are all things im sure the wiki explains, or i could figure out using a test print, but struggling in forums is definitely more my speed.

I understand completely.

I will be playing with TPU on a printer later today for a different reason.

I will try it out as I am interested in the answer. I will be using the PAUSE method and without an AMS in the mix.

I will report back on my results.

I am trying to find time to test.

I have found this video in the meantime.

You may wish to look as if this guy has succeeded.

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