You should dry your TPU before printing and you're good to go. I've had a lot of trouble printing TPU untill I bought myself a filament dryer (Sunlu fildrayer S2). You can also put it in an oven on 55 degrees C for 8 hours. Or better, look up the recommended dry temperature and time for your tpu. My biggest frustration about drying filament is that it is so unknown to most users. I had to find out by asking around on a 3d printing fair. Turns out that TPU, Nylon and most filaments which aren't PLA are very sensitive to moisture. Even PLA filament degrades in room conditions. I dry my filament before and after use and store it in vacuum bags. Even new TPU filament out of the box has to be dried before use.
@harrisonlow2 ай бұрын
Yes very good point! Before trying these prints I dried my TPU very thoroughly in my dehydrator at 55 deg C for over 14 hours. Still no dice 😢 I have noticed massive quality increases after drying TPU though, so it definitely helps a lot. I think modifying the geometry (and dehydrating before printing) is the way to fix my current issues 🤞
@KurinP2 ай бұрын
Just from personal experience on my own custom 3D printer, I've had less success with overhangs in TPU than with PLA/PETG/etc. In PETG/PLA I can get overhangs of 80-85 degrees, but with the same printer with TPU, I can only get 60. I know the average safe overhang angle is around 60, so it might be a good idea to do some overhang checks with your TPU. You also may want to experiment with z-hop, as it may be dragging the nozzle and ripping the TPU away from the previous layer.
@harrisonlow2 ай бұрын
Wow - those are some impressive overhangs with PETG! I think you're right; doing some overhang testing with my TPU would go a long way. I'll start one now and update the bellows model according to what I find. z-hop is an interesting idea! I'm hoping to print these in vase mode because it leads to a smoother, more aesthetically appealing part and I should be able to escape any issues with z-hop by doing so. Cheers for the suggestion!
@jakep41722 ай бұрын
For the problem that the bellows are trying to solve, what is the max range of motion that you are aiming for? +/- 1 degree? 5 degrees? Just wondering if you could use springs instead to provide a centering torque that allows the legs to twist but brings them back to a centered position.
@harrisonlow2 ай бұрын
Very interesting idea! In the lowest platform position the legs are angled at around 30 degrees from being colinear with the base nodes and the furthest they'd reasonably go is around 55 degrees. My biggest concern with springs would be their tendency to 'right' themselves to be straight again, and they'd need to be the perfect shape/size to fit both printed parts properly while still allowing the legs to move around without getting too bunched up at the tighter bends. I really like this idea! I'll keep it in mind as a potential option here 🤔 Cheers!
@jakep41722 ай бұрын
I meant something more like this: drive.google.com/file/d/1a4VqV4-HEj5oK0801tEVKnnVzSmEsAJ9/view?usp=drivesdk
@jakep41722 ай бұрын
Hopefully the sketch makes sense 😅
@harrisonlow2 ай бұрын
@@jakep4172 Ohh interesting - that's not what I thought you meant at all! I think I'd need to test this idea in real life to get a good idea of how it'd actually perform, though I have two main concerns with it that make me not so keen to try it: 1. The springs would physically get in the way of each other/the motor + encoder cables and be aesthetically unpleasing 2. These springs would interfere with the movement of the legs significantly more than the bellows do, leading to undesirable forces on the legs and hence platform Overall I like how different this idea is to anything I've considered so far and I'll keep it in mind, though I'm not sure it'd be a great fit for this specific application. Cheers for the suggestion! 😊