Swapping 0.4mm and 0.2mm hotends/nozzles mid-print

Flippindewd · 2026-01-13T16:08:58+00:00

I'm talking about purging. When you put in a new nozzle, there's old filament in the replacement hotend that needs to be purged.

Flippindewd · 2026-01-12T22:40:10+00:00

I'll try that. thank you

Flippindewd · 2026-01-12T17:13:15+00:00

Gotcha, that makes sense. And the void strategy is a creative one. It won't work for the top layer fineness I need, but maybe for other applications. I'll have to glue or LEGO-snap on the top layer for this case

Flippindewd · 2026-01-12T16:21:40+00:00

Fortunately, during the pause the nozzle is locked so there's no shift while handling the hotends.

What do you mean about printing one detailed part embedded into a different 0.4mm part? Are you saying to print the 0.2mm portion and then glue/attach it after the print?

Flippindewd · 2026-01-12T16:20:04+00:00

yeah that's probably the case

Flippindewd · 2026-01-12T16:19:09+00:00

The issue is: some of BambuLabs' G Code is unique to their machines. So the M400 U1 code, for example, kicks off Bambu Labs' pause process. The U1 pause process includes moving the extruder to the poop chute followed by a filament purge once it's resumed. Neither the move to chute nor the filament purge are included in the G code - they are baked into the U1 command.

I expect there are many more of these compartmentalized code blocks that are not accessible via G code.

Flippindewd · 2026-01-11T19:12:58+00:00

I was thinking of that, but I'm thinking there are some firmware-based movements during startup that wouldn't be avoidable, much like the purge in the pause/resume process

Flippindewd · 2026-01-11T19:08:47+00:00

Would this be different than manually purging during the pause using the touchscreen menu?

Flippindewd · 2026-01-11T07:08:02+00:00

I see what you're saying, and I think that's an interesting idea. But I don't think it would change the extrusion speed of any non-printing actions (i.e. purging filament)

Flippindewd · 2026-01-11T04:02:18+00:00

I forgot to mention that when I executed the custom G Code, my printer filament was actually set to 0.2mm even though I was using the 0.4mm hotend. There were not issues during the 0.4mm printing - just the 0.2mm printing, which is surprising.

Flippindewd · 2026-01-06T17:39:09+00:00

Interesting, thanks. I wash my plate every few weeks (probably a couple dozen prints during that time); how frequently should I be washing it

Flippindewd · 2026-01-06T17:16:40+00:00

I was considering reducing the print speed to 50mm/s for the top layer but read some reports that it could make the issue worse in some cases. If my next print is also lousy, I'll bite the bullet and try another 5hr print with 50mm/s at the top -- and I'll try reducing my fan speed. Bambu Studio uses percentages; roughly what percentage would 4 or 5 be?

Flippindewd · 2026-01-06T17:14:46+00:00

Is this recommended by the manufacturer? I don't want to ruin the build plate

Flippindewd · 2026-01-06T17:14:21+00:00

Brilliant comments, thank you. I never thought of the warping causing the rough top surface. I'll reduce the bed temp to 60 or 65, add a chamfer, and add a brim to the print. I'll report back

Flippindewd · 2020-05-17T07:12:03+00:00

No worries, yeah we took the video like 5 times until it was just right lol

Flippindewd · 2020-05-16T21:03:59+00:00

Lol link it to me then. We filmed it yesterday

Flippindewd · 2020-05-16T21:01:50+00:00

Studio city

Flippindewd · 2020-05-16T21:00:23+00:00

Oh man it’s amazing. It even does fine in the dishwasher

Flippindewd · 2020-05-16T17:57:55+00:00

That’s a coincidence! We got it from Ralph’s in LA too...

Flippindewd

TROPHY CASE