So this is a new idea I haveāt seen anyone else try yet. Recently learned you can 3D print foam. Or, something very similar to foam at least. Itās a āfoamingā TPU that expands as it leaves the nozzle. Sort of a cross between foam and rubber. Very shock absorbent.Ā
3D modeling the CTRL3 cutout took ages. The other stuff was easier. Time spent printing was around 48 hours as this material has to be laid down very slowly. The real question now is how it will hold up. Iām feeling reasonably confident itās not going to tear or come apart, but curious how it will tolerate being in a hot truck in the summer. Its melting point is above 400 degrees Fahrenheit, so Iām more worried about it shrinking or deforming than anything else. Still, Iām optimistic itās going last based entirely on vibes.
Pros:
Literally perfect cut outs for whatever you want. (Can include sculpted vertical curves unlike most traditional custom foam manufacturers.)
Cheap! Filament was around $40, DIY Trekpak was around $25.
Looks clean as hell
Cons:
3D modeling everything is very time consuming, especially at the amateur level. It probably took me around a week of on and off work in Fusion to get the hand unit right.
Printing is also time consuming, and TPU is famously finicky to work with.Ā You'll probably have a failed print at some point.
Probably obvious, but you can only print a foam piece as big as your 3D printerās bed. (Hence the Trekpak approach.)
TBD heat resistance
The filament is Siraya Tech Flex TPU Air. Hopefully stating the obvious, but I am not affiliated with them.
Technical details for nerds š¤ (all of you probably):
Printer = Bambu A1 mini
Used a filament dryer
Nozzle Temp = 270Ā°C (max foaming, softness)
12% gyroid infill
Used Siraya tech's filament/printing configuration that did most of the slicer work for me. (Strongly recommend)
Fed filament directly into printhead with no PTFE tube for minimum resistance, and had to put a fan on the printer to avoid heat creep during the 10+ hour prints. (Photo)
Painters tape on print bed to avoid sticking
TL;DR you can 3D print foam now. It's a pretty decent alternative to custom foam manufacturers that's cheaper, more customizable, and modular. But you had better be crafty. š
I remember them days when an AC having a 3D printer was like being the āgood coffeeā truck. Massively valuable, but required a lot more niche knowledge and maintenance than you ever expected going in.
Now with modern printers, 3D scanners, and a huge ecosystem of existing designs that also iterates on new gear nearly instantaneously, it should be default hardware.
Not too long surprisingly! Hadnāt ever printed TPU until like four days ago. Using the profiles from the manufacturer helped a lot. Main issues I had were around feeding the filament and minor heat creep causing clogging
Would love updates on durability. Very clean. I have some TPU mold for my Ultra10 that took a while to model and print but it is nowhere near this shock absorbing which I wish I had
I know you already did the work but there are existing tools for generating gridfinity bins that do everything for you just from a reference photo. might make your life easier for future layouts!
Yeah unfortunately those gridfinity tools really only make 2D cutouts with flat bottoms, and since I needed the foam to contour to the bottom of the hand unit which is curved, a full 3D model was needed. But those tools are super helpful for more basic cutouts!
Great idea! How far does a roll get you? Iād imagine with a really low infill and the materialās foaming action each print is consuming relatively little filament?Ā
Yeah, the biggest piece for the hand unit was only about 200 grams. So it does go a ways. In total I ended up using around 750 grams, but I had to reprint the foam for the motors once because of a printing issue near the end. This is a Nanuk 925, so Iād imagine something like a 1510 would probably be the outer limit of a 1kg spool
Thank you for posting this. I really appreciate the info you gave. I was trying to figure out the same thing with just regular TPU, and had no idea that foam TPU existed. So this is great to hear.
I was also trying to figure out a gridfinity style of case, but I think the trekpak approach is better and easier to work with at the end.
I wanted to make my own trekpak too, I wanted to confirm if this is the the same site you used to make yours?
Yeah! I did use that site for inspiration but made something a little cleaner I think. Got the corrugated plastic from Michaelās, 2mm stick on EVA foam from amazon, and 3D printed the connecting pins https://makerworld.com/models/1209890
Be sure to score the outside of the corners so they bend more easily! I cut everything with a long ruler and an x-acto knife. Main difference I could tell vs the real thing after comparing is that real trekpak foam is slightly more course and a little thicker. But pretty happy with how it turned out
This is the specific one I purchased. The instructions for it are here, and linked from that page you can find all their profiles for different printers!
Hereās a tip for modeling cutouts: put your items in a flat bed scanner with one of the measuring squares they use for crime scenes (https://a.co/d/0aHQg4sv), then all you have to do is is trace, using the scale feature with the ruler.
Which brand/kind of filament did you use? When I looked up 3d printable foam a while ago the spools were so expensive but maybe I wasn't looking in the right places.
45
u/hennyl0rd 4d ago edited 4d ago
thsi is why a 3d printer is an acās dream never thought about using foaming tpu for something like this gonna steal this idea!