I have printed most of the parts successfully with some minor imperfections and a few print fails.
I am having more trouble with the parts printed in TPU 95A.
I did buy the filament from BambuLab and am printing on A1. I did purchase a filament dryer and have dried the filament.
I have printed the tires without issue.
I had the straps and fail but have since spread them out and printed less at a time.
I am having trouble with the cushions. Since I had one fail, I have tried printing the back cushion and seat cushion separately. The back cushion printed but in the holes in the model for the straps, I am having alot of sagging. I was just using the files with the settings as they were uploaded. So it doesn’t seem to print with any supports.
For the seat cushion, I had good adhesion on the first layers and 5 hours into the print it seemed to be printing well. However when I checked is 3-4 hours later (when I woke up) it seemed it was a bit mess of stringing filament. It had printed 4+ inches high well, but then it seemed that it fell off of the build plate and was on the floor.
I have ordered some Bambu Lab adhesive to see if that helps.
I did notice that the speed for the infill is quite quick and so am wondering if that was perhaps too jarring (in the absence of using adhesive) and contributed to losing contact with the build plate.
Would slowing down the speed be helpful? Or am I on the wrong track? (If it would, just not sure what parameters to alter).
I am going to buy some Dawn dish soap and wash the build plate and wipe with micro fibre cloth.
Does anyone have any advice on printing the seat cushion given the problems that I noted above?
Can anyone give guidance as to how it should print where the holes for the straps are?
I have attached some pictures of this. (There is some imperfections beside the holes on the seat cushion? Is that indicative of filament being too wet or too dry - if I may have overdried it?)
My tires printed well, but I had some issues with the infill pattern popping through on the cushions. I added another wall and it printed much better. Would probably be better adding 2 walls. I had similar issues on the holes where the straps go through. No printing fix, I just trimmed the loose ones and used super glue in some areas.
My cushions came out the same as yours. I’m not sure what to do about it as I’m a novice. I just keep thinking of the child sit on it will cover. It just doesn’t look great.
What I can tell you is that I had all the same issues and tried many combinations of solutions: calibration, infill, max volumetric speed, retraction… to no difference. I was blaming the filament brand, but your result looks exactly like mine.
In the end, I placed the cushion in the chair; after all, it’s functional. But I’ll try again later.
@MakeGood_Noam Are you able to provide some guidance as it seems I am not the only one with this problem with stringing filaments where the slots for the straps are.
(I was able to print the seat cushion using adhesive on the print bed but again all of the holes have stringing filament like in the picture above).
Any guidance would be welcome.
Thanks for all of your work and for sharing this project!
Amy
Hey yall, thanks for your excellent work supporting eachother. TPU just likes to sag. We havent really found a good solution to this (you can print with supports, but I feel its not worth it). I have been trimming the sagging threads. Like was mentioned, it will be covered.
Since the petg/pla will not adhere to the tpu, I’m wondering if you can add supports and just print it with the supports being one of the other filaments? There is a setting in Bambu slicer where you can do that. Instead of pausing the print and trying to figure out the size that you want to put in there for the block.
Things were going well. Tires are coming out great, and the headrest is good… the cushion has been a challenge. So far all of my attempts have failed at the 10 hour mark… wondering if that’s the height things start getting a bit wobbly since there are no supports? Is there something in the file that I’m missing that’s causing the issue? I’m in trouble shooting mode but would love to get someone’s opinion on how to get this resolved…
This may be a reason for me to give the foaming TPU a shot but not everyone is going to invest that much in that filament.
I’ve attempted it on my Kobra 3 v2 twice in the vertical position and the prints seem to have issues around the 10 hour mark. I ran a test and ran it on my Kobra 3 max in the horizontal position and oddly enough, the print had issues around the same timeframe… I’m thinking that my slicer is doing something odd in a line of code. It literally stops extruding for no apparent reason… headed back to the drawing board. Lol
The tires are printing well. I’m using the identical brand of TPU with the same settings. I did tweak the settings during the horizontal test print but they were minor.
During the test print, you can see that it just stopped extruding… idk but I’ll give it another go after work.
Disable retraction. It doesn’t really help with TPU anyway, and can cause problems with extrusion.
Check the filament path. If you’re using a filament dryer with PTFE tubing, make sure the tubing is as short and straight as possible. Too much friction can prevent the filament from extruding reliably, especially with TPU. (I bet that’s not your issue though, or you would see it earlier in the print).
Thank you very much for the feedback. I did not think about the retraction and will definitely turn it off, as I agree with you 100%.
I’m using an external spool since it will not feed with the ACE. I dry the filament for hours, sometimes days before printing. I was showing 10% humidity in the box before the last print. I also have a dehumidifier in the room which was at 30% during the print… I do have a Polymaker dryer/storage box that should be delivered today. I’m hoping that will remove the consistent feeding and humidity factors from the equation. The current external spool is one I 3D printed with roller bearings, and who knows what kind of hangups could be occurring while I’m asleep.
Very long response to say thank you very much and I will make the suggested changes!
I’m going to ask for a link for this support.
