Conductive Flexible TPU Filament

Talk about materials used in 3D printing

Conductive Flexible TPU Filament

Postby ktfergus » 2016-Nov-Sat-16-Nov

I began looking around today to see if anyone made a conductive TPU filament for a product I've been working on; an adaptive stylus. I've found two suppliers so far: Palmiga which looks promising, but the entire check out page is in Swedish, & there's Black Magic 3D but I don't want to pay $45 for a measly 100g.

Does anyone know where else I might be able to get my hands on a roll of Conductive TPU?

-Kelly
  • 0

PrintrBot Model: 1403 (Simple Metal Assembled) :: DIY Heated Bed, with 305mm Extended X Axis
PrintrBot Model: 1403 (Simple Metal Assembled) :: 305mm x200mm DIY heated bed
PrintrBot Model: 1505 (Play) :: 100mm x 250mm DIY heated bed
PrintrBot Model: 1503 (Play) :: 100mm x 100mm DIY Heated bed
Latest Project :: Sisyphus Whirligig
User avatar
ktfergus
Printing skirt...
 
Posts: 160
Joined: 2015-Jan-Thu-14-Jan
Location: Los Osos, CA
Reputation: 16

Conductive Flexible TPU Filament

Sponsor

Sponsor
 

Re: Conductive Flexible TPU Filament

Postby RetireeJay » 2016-Nov-Sat-21-Nov

Several years ago, I was trying to find conductive epoxy (no, not for 3D printing, and not flexible). The best that I could find was extremely expensive, and even at that it wasn't particularly a good conductor. Basically, it was an epoxy mixed with a high proportion of finely-ground silver, which accounts for the expense.

I've heard that there are organic (i.e. plastic) conductors nowadays, and carbon nanotubes can be conducting, but I doubt you'll find an inexpensive, flexible plastic that's anywhere close to being a good conductor of electricity. And as the plastic flexes, expect the quality of conduction to vary with the deformation and also have residual changes after the deformation is over. It's a really tough problem, and if anyone does come up with a very cheap and reliable way of making excellent electrical conductors that are truly flexible, expect a huge explosion of applications in smart clothing, automation robots, etc. etc. Since we don't see that right now, that tells you the problem hasn't been cracked.

I recommend instead using standard plastics and then conductive paints or very fine springs to minimize your expense while achieving some degree of conduction.
  • 0

Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick
"My next printer is..." Prusa i3 MK3
User avatar
RetireeJay
My next printer is...
 
Posts: 4936
Joined: 2013-Jan-Wed-13-Jan
Location: Greenville, SC
Reputation: 495

Re: Conductive Flexible TPU Filament

Postby ktfergus » 2016-Dec-Thu-19-Dec

I recommend instead using standard plastics and then conductive paints


I considered doing just that, initially, but then I came across conductive PLA which worked well for my needs.

Just in case anyone is interested, I brushed up on my Swedish & purchased half a kilo of the conductive TPU from Palmiga. With shipping & the exchange rate it ended up costing around $75. At that price, I'm happy & relieved to report the stuff really works! It prints & behaves just like regular TPU or Ninja Semiflex. It's not a perfect conductor, obviously, but it does the job for my application.

Up to this point, I've been using conductive PLA on one half of each stylus with a TPU part bolted onto it to obtain an adjustable fit. However, conductive PLA is even more brittle than regular PLA & I was never completely satisfied with the layer adhesion. Plus, I still had to print & attach that second part. Now the whole thing is conductive TPU.

Here's the final product:
Image

I had hoped to eliminate the nib & print the entire stylus in TPU but I found that you need a fairly large cross section/surface area to get a captivate screen to react to the conductive TPU.

-Kelly
  • 1

PrintrBot Model: 1403 (Simple Metal Assembled) :: DIY Heated Bed, with 305mm Extended X Axis
PrintrBot Model: 1403 (Simple Metal Assembled) :: 305mm x200mm DIY heated bed
PrintrBot Model: 1505 (Play) :: 100mm x 250mm DIY heated bed
PrintrBot Model: 1503 (Play) :: 100mm x 100mm DIY Heated bed
Latest Project :: Sisyphus Whirligig
User avatar
ktfergus
Printing skirt...
 
Posts: 160
Joined: 2015-Jan-Thu-14-Jan
Location: Los Osos, CA
Reputation: 16


Return to Material talk

Who is online

Users browsing this forum: No registered users and 1 guest

cron