Have you wanted to 3D print flexible fabric prints? A good friend tagged me in Facebook, showing me a video of rigid filament printed over a layer of gauze. In this video, he demonstrates how a ridged 3D print can be printed with a fabric layer to give the print incredible flexibility. This is great for cosplay armor and medical applications.

Author with jar opener / headband flexible fabric, NinjaFlex printed onto a t-shirt. Photo by Author

I’ve seen other 3D prints in the past where someone has 3D printed a ridged logo onto a T-shirt, and it has been a technique that I have wanted to try.

Test 1: NinjaFlex on a T-shirt

I was not quite comfortable printing on a shirt I would wear, so I decided to sacrifice an old T-shirt to test and cut up first.

In this video it describes starting with a base layer print, then pausing and laying down the fabric layer, finished by printing over the fabric.

This method may work on very porous fabrics like gauze, but it does not work on tighter knits like t-shirt cotton. I gave up after two tries using his method.

Take 1

In the time it took to print the base layer and pause the print, the base layers had cooled to the point the fabric would not stick to the base layer. When I resumed the print it would not connect through the t-shirt to the base layer. The result was a smudged mess of flexible fabric

Take 2

I wanted to print something useful with this method, so I hacked out a jar opener in AutoCAD 2014. I modeled it after a couple of freebie ones I got at a job fair.

I was hoping the flexible fabric would provide a tight grip to open jars (I found out latter that Ninjaflex is fairly slick, and did not work as a jar opener).

I also wanted to see if I could 3D print flexible fabric on the MOAR extruder.

I employed the same method to feed flexible filament through the MOAR as the standard extruder.

I put a piece of scrap filament in the small gap at the bottom of the bearing, and tightened down the idler arms. Like before, the MOAR chewed through the Ninjaflex like crazy.

In this attempt I clamped a section of T-shirt across the build plate. This worked ok, but I did not see that the fabric would move on the y-axis. While it did not matter for this design if it was smudged a bit, I realized that the fabric would shift on the y-axis even if I clamped it down along the edges.

Take 3

The third attempt went much better. This time I used double-sided tape to secure the fabric to the whole surface. I also applied a liberal amount of clips to the bed. The third print came out great with no shifting on the build plate.

With a different design and a rock steady fabric layer to print on, this jar opener turned into a work of multimedia art.

Test 2: Semi Flex over Denim

For the second test I wanted to see if I could make something that would incorporate a denser fabric into a useful print. I found half a bolt of denim, and I looked around at the possibilities.

I then looked around online for some slim men’s wallet patterns that I could modify for 3D printing. After hacking a design out in TinkerCAD I took all that I learned from before.

I found it works best when a section of fabric is cut big enough to just cover the build plate. Using a generous amount of double sided tape and binder clips, I secured the fabric taut to the build plate.

 Try 1

For the first attempt, I tried using NinjaFlex as before. But this time something just did not work. The filament just would not extrude onto the fabric, leaving a stringy mess behind. While it did melt into the fabric, the flexible material seemed to build some back pressure in the extruder head that stopped the flow of material. I’ll have to experiment further to see if it was operator error, or if Ninjaflex does not like denim fabric

Try 2

This time I switched out NinjaFlex for SemiFlex. This made a world of difference as the SemiFlex did not jam or bulge in the hot end.

For this print I pealed the old Ninjaflex from the fabric, which also provided a rougher surface that helped the Semiflex bind to the print. For the second attempt, the print went so much better. My only concern was at the end of the print, the Semiflex started warping at the corners and pulling some fabric up with it.

Despite the warping, the wallet was a success! It uses the semiflex to give it a semi-ridged form, while the material breaths and makes for a slim and comfortable mens wallet.

Slim mens wallet, flexible fabric semiflex over denim. When full the wallet measures 22 mm thick. Photo by Author

Flexible Fabric Printing

This method of 3D printing over fabric may not be a new method of 3D printing, but it is something that advanced printers can look into adding to their portfolio. It is a fun way to build printing skills, and it has multiple applications.

Cosplay could benefit from this method the most. Cosplayers can integrate complex prints over a fabric body suit, and then wear the printed suit as flexible body armor.

Medical Applications

Medical fields can benefit from this 3d printing method. Instead of having to deal with poorly fitted medical devices, designers can print biomedical sensors directly onto comfortable clothing. Other hospital gowns can be equipped with attachment points for various medical devices, which can be clipped on and off as the situation demands.

Diabetes patients can print and incorporate holders for insulin pumps into their clothing. For elderly patients, accelereometers or emergency call systems can be incorporated into their clothing.

Autism Applications

For children with Autism that are at risk of wandering, GPS tracker slots can be printed onto sensory-friendly clothing. This way the child will be more likely to have the tracker on them when they wonder, and less likely to remove it.

From my work with the Autism community, many parents have complained that their children chew on the collars of their T-shirts, destroying them in a few months. Durable oral chewing collars or other devices can be printed onto shirts, which would extend the life of the clothing.

Other Applications

Engineers and other specialty workers can print custom tool holders or attachment clips directly into their clothing to keep common tools on hand. In the future powerline workers may incorporate safety harnesses printed directly into their clothing, which would reduce the amount of weight they carry and encourage job site safety.

Athletes can add a 3D printed slot for their heart monitors or smart phones so they don’t have to deal with extra weight and straps that slip.

The military can also explore 3D printing over field uniforms. A printed field uniform may carry magazines and side arms more comfortably then the current system that uses carriers that attach to body armor. Other specialty uniforms can be printed for medics and EOD personnel to make them more mobile, or attach specialty equipment directly to their body.

Takeaways

3D printing flexible fabric is a fun method for advanced 3D printers that are comfortable with experimenting with their 3D printers. Here are some things to consider.

a. Lower the bed level for your fabric. T-shirts are 0.6 mm thick, and denim can run up to 0.8 mm thick. Check the thickness of your fabric before printing.

b. Print on the hotter end of the filament temperature for the first few layers. This gives the molten filament time to flow into the fibers and bond.

c. Use plenty of double sided tape and clips to secure the fabric to the build plate. As it heats the fabric may loosen or shrink, so monitor your print closely.

DISCLAIMER: 3D print over fabric at your own risk. Do not use nylon or other materials that can smolder or melt as the base fabric.