Hello! I’m using my H2D with Bambu PAHT-CF in one AMS and Bambu ASA in another AMS, one feeding into each nozzle. I’m attempting to print the main objects in PAHT-CF using ASA as a support interface, which is working fine. Adhesion is great (using Glacier plate). The parts actually survive the print, but only just because the Prime Tower does not behave as you’d like it. I’ve got video, but a picture is likely enough to demonstrate.
As you can see the ASA is being ripped off of the Prime Tower. I’ve had it spill to the sides, get stuck on a nozzle, even end up in a layer of a part.
I’ve searched far and wide and I’ve found lots of posts about using ASA with PA, but none specific to the Prime Tower and dual nozzle setup of the H2D. Best I can figure, it’s something with the ramming settings. I’ve slowed the print down to 40mm/s on the nozzles (both) and 80mm/s on the prime tower and it works relatively well… until it doesn’t. At some points the nozzle ignores the speed settings and just goes max speed, which is when it bunches up the filament as you see above and now the nozzles, both of them, will continue to rip that off and deposit it everywhere.
I tried turning off the ramming by setting length to 0 and it failed at layer 2. I increased the travel time after ramming to 20sec and it was better, but still does it. Perhaps I’m looking at the wrong issue, and I’m hoping someone has an H2D and is trying something similar to me. I know the 2 filaments don’t mix so I understand why it can rip off, but I also know it works fine most of the time, until it speeds up ignoring my settings.
Try doing not just interface layer but the whole support structure from ASA including base. It will make sure the prime towers full height is from ASA on one side, so you wont have issues with adhesion on the tower mid print. It will be a longer print, but will also save some PAHT waste.
I’ve been so stuck trying to solve it my way I didn’t think of that.
I just sliced that up and strangely enough, it actually increased the use of both filaments. PAHT by 2g and ASA by more of course. It didn’t make sense to me but looking through, I guess it’s in the strength of the prime tower and some other calculations it runs. I tried with ribs and without, reducing this and the other, but in all ways I went from 10g PAHT to 12 and overall from 12g to 27g total usage.
I think that would absolutely fix the issue I’m seeing and make the print successful.
I might try this method on my larger model I’m slicing, to see if I get different results filament wise. I started small because I’m very concerned that the Prime Tower will fail (or the print will be unusable due to contamination) if I went big as it sits.
What hotellonely said. They have basically resolved all the prime tower issues I was seeing in the latest BETA. Also it seems they improved supports? Idk they look more ‘beefy’ and better thought out if that makes any sense
I’m assuming the required 01.02.00.00 Firmware is actually required, and I’ll need to wait for it to load ota on my H2D?
EDIT: I’m going to go out on a limb and assume the min firmware listed on the Github page is actually incorrect and meant to be 01.01.02.00 because it was just 5 hours ago that the 01.01.30.00 firmware came out, nowhere close to an 01.02.xx.xx
Updated to the 01.01.04.00 beta firmware (awaiting the latest 01.01.30.00 to be applied ota) and the latest beta of Bambu Studio, no dice. This is a different print but very similar, using same settings, slowing everything down. This one even knocked off one of the ASA supports but I cannot blame that on the tower or ramming.
I guess for now the only option is to massively slow down the print and double the filament use to prevent this. I saw a video posted by Functional Prints Friday doing essentially this same thing with same settings and in the video the tower was perfect (perhaps it just is not in the video) so I feel like there is something that can be set for this.
I am having a similar issue with PA6-CF and Hips support. Have you found any solution besides a nozzle swap every layer yet?
My first few prints were successful so it’s clearly possible, but now seemingly randomly this issue will occur where the hips doesn’t stay on the prime tower.
I only caught it happening once and I didn’t notice any odd speed behavior, but I wasn’t paying close attention.
You can reduce tower print speed. But that only contributes a part to the solution. ASA/HIPS as supports just work better when you build the full support with ASA/HIPS.
