Print with rubber on your Lulzbot!

Help with printing with specific plastic filaments.
machadolab
Posts: 6
Joined: Wed Mar 12, 2014 5:31 pm

Re: Print with rubber on your Lulzbot!

Post by machadolab » Fri Mar 14, 2014 8:18 pm

What is fundamentally different about the flexystruder and that it requires a whole new extruder? Any chance an existing extruder could be easily modified to print ninjaflex?

User avatar
piercet
Posts: 4025
Joined: Sun Aug 25, 2013 1:37 am
Location: Battleground, WA
Contact:

Re: Print with rubber on your Lulzbot!

Post by piercet » Fri Mar 14, 2014 9:44 pm

The flexystruder constrains the filliament on all sides. A standard hobbed bolt idler extruder puts pressure on one side and supports half the filliament on the other side, which can allow for movement of the filliament which doesn't really affect more rigid filliament for printing, but the support missing on the sides causes flexible filliament to tend to bind and not print as well. You can mitigate that with a grooved bearing if you can find one the right size with the right shaft. There is one person that I know of making them in Hungary. It took me 2 months to get one here, and when it arrived it was the wrong size. The flexystruder lining will apparently wear over time with more rigid filliaments, otherwise it is fine for normal filliament as well.

bam
Posts: 117
Joined: Thu Sep 19, 2013 11:37 pm

Re: Print with rubber on your Lulzbot!

Post by bam » Mon Mar 17, 2014 3:23 pm

piercet wrote:The flexystruder constrains the filliament on all sides. A standard hobbed bolt idler extruder puts pressure on one side and supports half the filliament on the other side, which can allow for movement of the filliament which doesn't really affect more rigid filliament for printing, but the support missing on the sides causes flexible filliament to tend to bind and not print as well. You can mitigate that with a grooved bearing if you can find one the right size with the right shaft. There is one person that I know of making them in Hungary. It took me 2 months to get one here, and when it arrived it was the wrong size. The flexystruder lining will apparently wear over time with more rigid filliaments, otherwise it is fine for normal filliament as well.
Well put!

An existing extruder *can* be made to print, although it would most likely be easier to print the flexystruder body and assemble your own. Here's the work that the Flexystruder is largely based off of, (http://forums.reprap.org/read.php?1,269018,269018). It involved drilling out a standard extruder to fit the PTFE lining, then trimming the top of the lining to press right up against the hobbed bolt and idler. This was pretty difficult to get right, and tended to fail as the ninjaflex bunched up and pressed the sides of the PTFE out.

If you're interested in making your own, check out the Ohai-kit that Orias linked to:
Orias wrote:A Flexystruder assembly guide can be found here: http://ohai-kit.alephobjects.com/projec ... _assembly/

bam
Posts: 117
Joined: Thu Sep 19, 2013 11:37 pm

Re: Print with rubber on your Lulzbot!

Post by bam » Tue Mar 18, 2014 7:24 am

I've been getting a lot of questions about the thumbscrew on the side of the Flexystruder, and how to adjust it properly.

The Flexystruder can print Ninjaflex with very little tension on the thumbscrew, it's just there to enable you to print any undersized or extra soft filaments (we ran into a few during testing).

If the Flexystruder starts slipping on the filament, simply back the thumb screw out, then slowly tighten it while turning the large gear on the extruder. You should fee it noticeably start to catch on the filament; give it another half turn from here for good measure. and you should be set to flexystrude all day.

Cheers!
-Brent

User avatar
Theycallmejohn
Posts: 243
Joined: Sat Dec 28, 2013 6:05 pm
Location: Huntington Beach, CA

Re: Print with rubber on your Lulzbot!

Post by Theycallmejohn » Tue Mar 18, 2014 10:43 am

Lulzobot - Flexystruder got a nice little blurb in Hackaday. Though now the world knows about the scanner in development too... people are going to get anxious. ;)

http://hackaday.com/2014/03/17/mrrf-stu ... ore-117505

bam
Posts: 117
Joined: Thu Sep 19, 2013 11:37 pm

Re: Print with rubber on your Lulzbot!

Post by bam » Thu Mar 20, 2014 3:28 pm

Theycallmejohn wrote:Lulzobot - Flexystruder got a nice little blurb in Hackaday. Though now the world knows about the scanner in development too... people are going to get anxious. ;)

http://hackaday.com/2014/03/17/mrrf-stu ... ore-117505
Nice!!

As a side note, single layer sheets of ninjaflex are my new favorite thing. They're mind mindbogglingly tough, and we've just found that they can be used as static window stickers! We'll try to get a video up soon.
IMG_0280.JPG
printed flex sheets (.4mm thick)
Any application ideas? We're thinking custom window stickers, colorful privacy window treatment, even a small potted plant holder (although we'll have to see how much weight one of these can support) :)

Cheers
-bam

User avatar
Theycallmejohn
Posts: 243
Joined: Sat Dec 28, 2013 6:05 pm
Location: Huntington Beach, CA

Re: Print with rubber on your Lulzbot!

Post by Theycallmejohn » Thu Mar 20, 2014 4:16 pm

Bam,
Looks like you need to make a dual color Dual-Flexystruder. ;)

User avatar
Orias
Aleph Objects | LulzBot
Posts: 1509
Joined: Wed Mar 27, 2013 1:24 pm
Location: US

Re: Print with rubber on your Lulzbot!

Post by Orias » Fri Mar 21, 2014 11:00 am

I'm loving my Flexystruder! I recommend taking the time to measure the OD of the PTFE tube, and adjusting the hole to match as my 12" length varied widely. This is rapidly becoming my favorite filament type!

bam
Posts: 117
Joined: Thu Sep 19, 2013 11:37 pm

Re: Print with rubber on your Lulzbot!

Post by bam » Tue Mar 25, 2014 7:29 am

Theycallmejohn wrote:Bam,
Looks like you need to make a dual color Dual-Flexystruder. ;)
Working on it :)
Orias wrote:I'm loving my Flexystruder! I recommend taking the time to measure the OD of the PTFE tube, and adjusting the hole to match as my 12" length varied widely. This is rapidly becoming my favorite filament type!
Mine too! So many cool applications. Great point about the PTFE, it tends to be pretty inconsistent. You definitely want a snug fit, any sliding of the PTFE tube during printing is bad news

User avatar
Orias
Aleph Objects | LulzBot
Posts: 1509
Joined: Wed Mar 27, 2013 1:24 pm
Location: US

Re: Print with rubber on your Lulzbot!

Post by Orias » Tue Mar 25, 2014 7:55 am

On playing with it this past weekend, after finding some extrusion issues, the ptfe tube stretched a bit, so the initially flush-cut edges of the PTFE tube, now had an extra 1/8"+ sticking out the base. On the next extruder I make for a buddy we'll see if we can repeat that.

Post Reply