I am trying to get PETG to print as a support interface for my PLA prints on my A1 mini but just am not seeing any progress. I have tried Overture and Sunlu PETG. Dried them both at 65C for 12 hours each, which made no difference. I have printed objects with this roll of PETG and it prints great. The PLA and PETG both look great when printed separately, but for some reason, it is just not working. I’ve tried setting nozzle temps ranging from 225F to 260F. Tried bed temps at 70C, 75C, and 80C. I have tried altering the flow rate with calibration tests. I have tried slowing the speed interface speed to 20mm/s. My volumetric speed is currently at 8mm/s for PETG.
For support settings, I have tried Normal with default style and normal with snug style. And the rest of the settings are below
Top Z distance - 0
Bottom Z distance - 0
Base Pattern - Default
Base Pattern Spacing - Tried 2 and 2.5
Pattern Angle - 0
Top interface layers - Tried 2 and 3
Bottom interface layers - Tried 2 and 3
Interface Pattern - Tried Default and rectilinear
Top interface spacing - 0
Bottom interface spacing - Tried 0 and 0.5
Normal support expansion - 0
Support/object xy distance - Tried 0.2, 0.35, and 0.5
And my flushing volumes are set to 800mm when switching from PLA to PETG and vise versa. At this point, I’m not sure what to do to get it to print correctly, and would appreciate some guidance.
right-clicking an empty plate, and select add primitive → cube (50 x 50 x50).
Then add a negative part (60 W x 30 L x 40 H). Or both smaller to print faster, but if the legs are too small they may not stick to the plate without a brim…
Center both.
Right-click the large cube and select mesh Boolean, and the arch will be created.
Select PLA for the arch (a Bambu Lab PLA will have the standard presets)
Settings:
Select a 0.20mm Standard preset
In Support settings: enable support, select PETG for “Support/raft interface”, set “Top interface spacing” to 0.1mm (a Bambu Lab PETG will have the standard presets)
I watched this video recently that might be worth a watch where support interfaces including PETG support interfaces are tested in multiple configurations.
I did what you said, and left all the other settings untouched except for top interface spacing and this is how it turned out well. Turned out no better than all the other settings I have tried.
The photos below show my result using PETG as a support interface layer with PLA, for comparison.
Printer: X1 C with AMS (Firmware V01.07.03.00)
AMS: V00.00.06.40
Nozzle: Bambu Lab X1 Carbon 0.4 nozzle
Plate type: Textured PEI Plate
Filament: Orange Bambu Tough PLA and grey Bambu PETG Basic with standard Bambu presets as synced from the AMS (no speed, temperature or other changes whatsoever).
Process: 0.20mm Standard @BBL X1C
Process custom settings: Support tab only: support enabled, PETG selected for Support/raft interface, I forgot to reduce the Top interface spacing to 0.1mm as suggested above (see note below).
Slicer: Bambu Studio V1.8.4.51
Flow Dynamics calibration NOT selected when printing. This would only do Automated “Flow Dynamics Calibration” for the PLA, not the PETG. The “Factor K” is used for the whole print, and during every filament switch the printer will use the default “Factor K” for the PETG (I understand unless it is a BL PETG in which case the appropriate preset will be used based on the RFID identification of the filament - bit of a grey area as the documentation is ambiguous and I’m still trying to figure it out by looking at the source code)
Nonetheless, these are the only settings changed from standard:
If Top interface spacing was reduced, the gaps between the grey lines would be narrower. A 0mm setting would make a solid grey interface layer, which only marginally improves the first part layer above the support interface layer.
The first layer above the PETG support interface layer is not perfectly smooth, but it is more than satisfactory and illustrates what is possible using standard settings in Bambu Studio.
The Support/object xy distance could also be reduced to 0.1mm, particularly on small supported regions, and I’ve found that separation is still just as easy.
Bambu Studio and Orca could both do with settings specifically to improve the quality of the first part layer above dissimilar support interface material.
So to your problem…
I suspect that this is a filament issue, not a printer (even though you have an A1) or slicer one.
Try inserting a PAUSE at the first layer above the support, then take a photo when it stops printing of what the top layer of the support interface material looks like.
Try inserting another PAUSE at the layer above that and take another photo when it stops printing, to determine when the defect is first evident.
Using different colours may illustrate better if any PETG is left adhered to the underside of the first part layer.
Using different filament spools, preferably BL, may have better results. Not because BL filament is any better than others, but because the calibrated presets would be used, negating the need for calibration.
I’m about to give your suggestions a shot. It’s going to take about an hour. I’m doing three objects (print by object) with a couple of tweaked settings. I’ll update with my results after, but I wanted to get a couple of pieces of feedback because searching has been giving me answers all over the place (and sometimes the opposite of what I’m looking for).
Issue 1: My old bambu cold plate (sticker) was holding onto almost nothing, so I replaced it. This year has been a rough one so I haven’t printed in forever. Fast forward to now and my nephew is asking Santa for an action figure that doesn’t exist that was in one episode of a canceled Netflix show lol. Every print I’ve done on that is difficult to scrape off (using only PLA btw) and if the scraper won’t reach, the object breaks and stays stuck to the bed. Any tips on breaking this plate in? I’ve reverted to the textured PEI plate, but sometimes I want a smoother surface.
Issue 2: More related to this topic. In the past, using the Support W material has been fairly reliable. Sometimes the surface above it is crappy, but it at least stays brittle and peels off. Now it’s sticking to the object VERY tightly. I’ve tried drying all my filaments. Adding some Z-distance even though 0mm should work. One of the three objects I’m doing for this test I’m using the Support W to see if it’s fine on flat/geometric surfaces and I should just stop using it in more complicated shapes. In the past, neither was a problem.
That’s it! Either way, my real purpose was to test the primary subject of this post. So if you or nobody has feedback or even a link to a separate post I should’ve been able to easily find on my own I won’t fuss
Happy that it was of some help!
I won’t fuss 