This is something that I was thinking of for a while, but latest failure with printing cushions pushed me to actually try it. In a nutshell—Yoga mat. $23 on Amazon. Pair of scissors, Exacto knife, and failed set of seat cushions to trace the outline. I am not the best at arts and crafts, and this is my first attempt….but in my opinion, this is a way better option than what can be 3D printed. Here is why:
Comfort—plain and simple, these are more comfortable than current version of seat and back cushions printed from either regular TPU (95) or TPU Air. I performed the following tests: I currently have only ones printed from TPU 95, but my second build had ones from TPU Air. Both were printed with 2 walls/10% gyroid infill. I did “ass to cushion test”—its more comfortable to sit on the one made from 1/2” yoga mat than on 3/4” TPU–it feels very even vs bumpy (infill). Based on my memory, one printed with TPU Air was slightly more comfortable, but it compressed very easily and gave me the impression sitting on a very thin mat. I also did a “knee to cushion” test—yoga mat wins hands down.
I understand that the goal of this project is to be as 3D printable as possible. I think it is great that it has only a few non-plastic components, but I would like to make an argument that if this project is created in an area where there is access to 3D printers and filament, it would be safe to assume that a yoga mat or other type of rubberized cushions is also accessible. I don’t think it is wrong to take advantage of resources we have access to, especially if there is a better result.
Please share your opinions and suggestions! @MakeGood_Noam
So I think this looks great! Would also love to know if this is an ok alternative.
Printing my first set of headrest/cushion with the Siraya TPU air and getting a decent amount of stringiness despite several dry cycles. Need to get a dehumidifer going in my print room I think but if this is easier and potentially more comfortable this could be a great option as well.
I may make a set anyway with the yoga mat and just give them as an additional option when I deliver the chair.
Everywhere or just the holes? I’ve been using avoid crossing walls. I also removed the holes from the upper cushion and removed the bottom filets. I’m going to add a less aggressive filet to the bottom front, because the bottom edge just feels a little hard, but the cushion came out flawless, no nubs at all and a perfect back seam.
Thank you! I don’t mind stringiness as much as the comfort. Maybe I haven’t experimented enough with TPU Air, but I felt that with suggested settings it felt very thin to sit on, granted, it might be more comfortable for a child vs a 200lb gorilla.
This feature is in my top 5 most useful things I learned! On an unrelated topic, I started printing your design this morning with TPU 95. I had one print failure (operator error), but the part that printed felt way more comfortable squish-wise (2 walls/10% Gyroid infill) and the infill seemed to be distributed differently from the original. I don’t know what you did to it, but it is a great design!
There is some stringiness with the TPU Air that can’t be helped unfortunately. It is pretty messy. I have “Avoid Crossing Walls” enabled, which helps, and I only print one cushion at a time. And to avoid any clogs I completely turned off retraction (which for my SOVOL printer I had to go in and disable some timelapse macros that were triggering retractions, even though I don’t even run timelapses).
This stuff also makes a mess all over. When it oozes out of the nozzle the cooling fan makes the little strings break off and blow all over the place. And little bits of it stick to the build plate all over. The first roll I got was white, which was awfully messy. Now I’m using black - it’s just as messy but blends in more so I don’t see it as much
I really like this idea, the cushions are annoying to print especially with the TPU AIR. The AIR just oozes so much out of the nozzle there is so many weird strings on it, plus the slits don’t print well at all.
A yoga mat seems like a great option, you really just need a template and you can easily cut them out. Plus families might like this if they need replacements in the future they can just cut their own.
I delivered one TMT today, and one of the questions asked was where to get replacement cushions. After I mentioned that it was made from yoga mat, mom got really excited about this option.
I don’t think it will be an issue if you pick the right settings (fyi, I know nothing of operating one). One of my worries was fraying edges, and I thought about torching them–same principle of burning ends of woven rope so it doesn’t unravel. It was not needed for this particular one, but it is an option.
The stringing wasn’t everywhere mostly in specific lines (vertical lines) throughout the print. I actually aborted a print this afternoon because one, the infill was just falling away causing the subsequent layers to print in air, and second yeah the holes were definitely an issue. I was printing on the second softest setting though so I think after another drying session Ill adjust up to the harder setting and try again.
I got the headrest out clean and had to do some minor cutting of stringing but it came out well.
Honestly, my first attempt at TPU was the sample strap that was part of the application so I’m still learning in that regard. Will definitely try out the option presented without holes, and worst case I have some 90A white TPU I can use instead for the main two cushions.
We got some rain the last few days and I just got a dehumidifier for the print room so that could be the culprit as well.
Love this, I think this can be a really good option for replacement as needed and can give back a little control to the parents to be able to do this for their child if they want to!
I am loving the ingenuity here. I’m perfectly fine with the yoga mat, and I think it’s simple enough that a family can make it if they want another option. My friends company uses sheets of EVA foam (testa seat) and it works great. There are people also sewing cushions the old fashioned way.
Seeing that cushion with no holes makes me want to copy the same design, and simplify it. I will talk to the team
One thing to keep in mind, kids are light. They need as soft a cushion as possible. It’s hard for us 200# people to comprehend. That was the advise given to me by a seating specialist
Thanks, but I will never take credit for the design. Whomever is designing these are masters. I just was trying to come up with a solution for my inability to print the cushion top with holes…lol. I do believe there needs to be a small curve on the bottom front edge, but not as aggressive so there are no overhanging walls.
I should have said modified—it is still a great part. I just finished reading a comments in Posture/Seating Analysis by @Eameschair : I think any holes in 3D printed cushions can create possible sources of pressure just due to the way they are printed. Walls for the former are running perpendicular to infill, and you have eliminated those.
