Flexible Filament Jammed in Toolhead

Flexible filament jammed in toolhead

I’ve been printing with flexible filament for one year now and it’s been fun.  It’s sometimes called elastic filament by others around the world.   Depending on the feeding mechanism for your printer you may not be able to print with flexible filament. Imagine pushing rope; if there is a place besides the barrel for the filament to go, it will.  There are so many 3D printers and I only have experience with my own so for specific printer settings for flexibles I would recommend user forums or the reddit 3d printing community. To give you an idea of what can go wrong check out this trouble shooting guide.

3D printer mod to allow for printing of flexible filaments

Mk8 Spring loaded Drive Block Replicator 1 / Duplicator 4 / FlashForge / CTC

There are many printer modifications you can 3D print yourself.  The MK8 pictured above is one of the more popular mods in my Thingiverse collection of printer mods and accessories for flexible filament.

My first 3d print was for a co-worker

My first flexible print

The very first thing I printed with a flexible material was a phone case for a co-worker . Then I had to print one for myself.   Phone cases are very functional especially if you drop your phone as often as I do.

DUT ties: fun and functional

One design I found that was both functional and fun are DUT ties.  They are flexible, resusable ties and straps  for cords, cables and more.  In fact the company MUTDUT is going to launch a full line of ties on Kickstarter later this year.  After printing off several ties, I got inspired to print their soccer ball design.  They made it look so fun! 12 pentagons and 36 ties later I had my soccer ball.  It’s a hit with kids both young and old.

Single flexible filament extruder retrofit kit: Flexion Extruder

Fortunately there are extruders you can purchase to retrofit your existing printer like this Flexion Extruder.  I purchased a Flexystruder for my Lulzbot Mini which works quite well and allows me to print flexible filament as easily as ABS or PLA.


Flexible filament goes by the handle of TPE or TPU.  TPE – Thermoplastic Elastomer is the main category of material. Here is an interesting web page from PolyOne on TPEs.  TPU is one of 6 traditional classes of TPE: Polyurethanes.

my most difficult 3d project to date

My most difficult (and favorite) 3D project to date

This popular 3D printed project is the OpenR/C Formula 1 Car by Daniel Noree.  You don’t print the whole car in flexible but you do print the tires. Here are other OpenR/C projects: OpenR/C QuadcopterOpenR/C Truggy and OpenR/C Touring Car.  The Quadcopter is on my bucket list. I have often thought some of the other parts would fare well being printed in flexible filament because the impact strength is much better than ABS or PLA. However I have found that models that snap together don’t work as well with flexibles. There is just too much give. I tried scaling some of the pins on the Raptor Reloaded by e-NABLE Prosthetic hand.  I didn’t have a lot of luck, perhaps an engineer would.

This decal is 3D printed with Shore Hardness rating 85A filament

Save a bird from crashing into your windows with a 3D printed decal made out of flexible filament. These stick best to windows, walls and mirrors with lower shore hardness flexibles such a NinjaFlex (85A) or FilaFlex (84A). Shore Hardness is measured by a Shore durometer.  One of the most common scales is the Shore A scale.  Hardness is often confused with other properties such as flexural modulus. Although both properties reflect how the product feels in the customer’s hands, flexural modulus measures the resistance to bending, while hardness measures the resistance to indentation. Within a specific TPE family, these two properties are related. Generally as hardness goes up in value, so does flexural modulus.  A non scientific illustration of these properties are illustrated in my video which shows a stretch test, squish test and flex test.  Most of the flexible filaments are flexible but not all are squishy and stretchy. That being said, if you don’t have a modification to your 3d printer for flexible filament try your luck with the stiffer 95A-98A flexibles.