PrintrBot NinjaFlex Upgrade

by adafruit, published

PrintrBot NinjaFlex Upgrade by adafruit May 20, 2014



Read the full installation guide on:

NinjaFlex is our favorite TPE based filament becuase it works great with our wearable projects.

If you've ever tried printing ninjaflex on a PrintrBot, you may have notice a small problem. It doesn't extrude so well. TPE material is so flexible that the filament actually buckles just before reaching the hotend. The drive gear and the hotend are so far apart that the filament can actually tangle!

Our 3D printed filament upgrade eliminates this problem by guiding the filament directly to the drive gear, removing any room to buckle.

Designed to print right on your printrbot in just ten minutes, the installation is easy and requires no extra parts.

Parts list:
On/Off DC Barrel
Extension cable

Recent Comments

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I printed 2 and both broke, one in installation and one in operation (before any ninjaflex was printed) I tried using PETG with no luck.

2 of them broke for me as well, one in installation, one in operation - before getting ninjaflex to print.

2 of them broke for me as well, one in installation, one in operation - before getting ninjaflex to print.

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PLA or ABS @230
.2 Layer Height
2 Shells
10% Infill
90/90 Speeds

for ABS heat bed to 120

I printed 2 and both broke, one in installation and one in operation (before any ninjaflex was printed) I tried using PETG with no luck.

2 of them broke for me as well, one in installation, one in operation - before getting ninjaflex to print.

2 of them broke for me as well, one in installation, one in operation - before getting ninjaflex to print.

2 of them broke for me as well, one in installation, one in operation - before getting ninjaflex to print.

Mar 11, 2015 - Modified Mar 11, 2015

I printed three of these…all broke. I ended up using the top half of another design that has a free straw like bottom along with the design that is addition to the extruder input.

Bottom http://www.thingiverse.com/thing:439617

PrintrBot Metal NinjaFlex adapter
by dubi

We were able to print this piece, but it didn't work with our printer. I had to break off the bottom guide-hole piece because the extruder has a hump with a guide hole already. However, after doing that, it fit perfectly. Of course I had to adjust the tension but in the end, I haven't had a problem.

I did, however, have to play around a lot with the settings to get a decent print. I don't have it "perfect" yet, but have had some pretty good results. If anyone is interested, please contact me and I can share a link to our Blog.


So, I, much like everyone else on this thread, have had trouble printing out this part.

I did however get printing with ninja flex to work, but not using this.

If your having trouble with this, take apart a ballpoint pen, and snip the plastic tube off the end where there is no ink. This is exactly the right diameter to fit in the extruder.

what kind of pen

Thanks so much!!! the pen thing works

No problem. I'm glad it worked for you.

This part sucks. Adatruit is too high quality a company to put out such imbecile garbage. Did you even try to print it? I could go on with all the reasons that I have wasted probably eight to ten hours of my life trying to get this part to work, though I am sure that these issues have already been stated. To Adafruit: "Fix this thing or I will never buy one of your products again, and will recommend others avoid your company". I have been a strong proponent of Adafruit until now, and suddenly you've removed the telephone number from your website so I cannot call to get someone rational to speak with. This situation sucks.

Les Hall

This comment has been deleted.

I tried printing this several times and was able to get it to print correctly, but it was so fragile that when I would try installing it each time it would break. Eventually I found out you needed to flip the hobbed driver around so that there is a space between the driver and the motor. After I did this, I ended up just ordering one from Shapeways for about $9 US using the "print anyway" option. It is now extruding just fine and I am able to print with Ninjaflex!

Those who are having trouble printing/fitting this one can try http://www.thingiverse.com/thing:524171, which is a bit simpler two-part design (based on this one). NB: see the WIP notes before printing.

NinjaFlex upgrade for PrintrBot Simple 2014.1
by jonnor

In the end I gave up and sent the STL to Shapeways to print in "strong plastic" (essentially laser sintered nylon). Each print costs only a few $ (plus $5 shipping). Note: you have to choose "print anyway" option since their error detecting algorithm flags the part as having "thin walls" and they will not print unless you choose the "print anyway". The quality of their print is great! I will put it into my printrbot soon and then buy ninjaflex.

This piece is just impossible to print. Once you cut the supports off the whole thing breaks down. Can some enterpreneur make them in some better way (CNC carved? acrylic) and sell them?

I am also having problems with this breaking upon mounting it. The problem seems to be around the smallest tube.

Nerq - in reply to Nerq

Fixed this by stopping the print after it had finished the two holes for the filament, and not printing the back part (seems to work so far, and I have printed a few Ninjaflex prints with it). It is also able to print normal PLA.

I've printed NINE of these in different orientations, slicer settings, and support material settings. All break when I attempt to remove the support material. (sob)

I'll just order one online.

Can you leave this part on when you need to print with PLA or ABS?

I'm having a problem here. I can't seem to get it tight enough to get the bearing to put enough pressure on the ninjaflex to provide a good extrude. Any suggestions? I've tighten the screw all the way past where the bolt isn't even in the channel anymore and nothing.

Printrbot should have this injection molded or machined from aluminum and sell it on their website.

Apparently there are some variations in the extruder design for different units. Sadly I am in that boat. I am not the best designer but it would be nice if someone could design a remix that actually works.

Yeah I agree. This isn't doing the trick for me. I'm going to try to make changes but I don't have much experience and may have counted on this working a bit to much since I now have Ninja Flex filament that I cant use until I figure this out.

If I print with supports, do I have to cut off the excess material in order to use it?

Yes, but good luck trying to get it to fit. There seems to be some variations to the extruder on different units.

Yup. I experienced that. I could not get mine to fit at all. My hobbled gear is right above the top of the hot end so there's no room. If I feed at a rate of 15mm or lower it does alright. The suggested 30mm ends up just wrapping around the gear.

I tried to have it printed at shapeways and they said they couldn't due to thin walls.

They now do, but you have to mark it as "Print Anyway".

Just my experience, I was not able to print this part due to the thin walls, kept breaking at the supports. I had it printed at shapeways for a few bucks, installed it, and it works beautifully. prints ninjaflex consistently! Thank you adafruit.

Hi, what program is that you are using to print in the video. Thanks.

I think they use Simplify3D

having issues with it being very weak near the hole on the part that goes under the bearing. Printing on my metal simple with settings in the instructions. Printed twice and both times the piece broke at the same spot. :(

Their settings can be VERY different from what you'll need to print at depending on the filament you're using. I printed mine at 15% infill, totally different speed and acceleration and a totally different temperature. 230 for PLA is REALLY high. The filament I used likes about 195 first layer and 190 subsequent layers. BUT - that place youre talking about is fragile anyhow, you definitely have to be careful when removing the support.

Thanks for this! Brilliant.

Note: After doing several prints, modifications and research, this is ONLY for the new Metal simple and the NEW (5/24/14) Simple makers kit. Not directly compatible with any other version of the simple as the extruder and direct drive are different! Im trying to work on a remix for those of us with 2014 Simple's or a simple with an upgraded alu extruder.

Have you got a version that works for older printers yet? I want to know whether I should start work on one or not. Thanks!

Can someone share how they sliced this? I am new to 3d printing on my simple metal and can't get it to slice correctly. http://i.imgur.com/iwE9zly.jpghttp://i.imgur.com/iwE9zly.jpg <- That is what I see before and after slicing which cuts out part of the hole! I am using the configuration files provided by Printrbot in slic3r inside of repetier-host V0.95F. I originally printed it out before checking the gcode and it also printed with the hole in it and without support structures when I used the support model provided. Thank you for your help!

Just tried it and I'm getting the same result

Im using 95F and it sliced fine... that is weird. Did you try the version with support as well?

I seem to have found a fix for this! It appears as if the problem was the slic3r version I was using was not working properly, so I switched to an older version located the slicer manager in repetier. I picked Slic3r version 0.9.0 - 0.9.8, and exported the gcode from the different window that popped up, loaded it back in repetier and it looks good. Printing it out now :)

Nice job.

The 3-D printed part is designed for the new version of the Alu Extruder that is only found on the new Printerbot Metal Simple. I have a Printrbot Jr. (V2) that I have upgraded with the aluminum extruder upgrade from Printrbot, but because the aluminum extruder is a different shape (see this image: http://i.imgur.com/ZeXoj4m.jpghttp://i.imgur.com/ZeXoj4m.jpg, the silver one is the older edition, the more pinkish one is the newer one found on the Metal Simple), I cant use the 3D printed part. Could someone add a version that works with the older extruder?

I'll followup my original comment - I have the new extruder and this piece still doesnt fit mine. I've been making changes for the past little bit to get it to work with mine. My thought is that printrbot once again made slight changes to the extruder assembly and tolerances are off.


My 2014 wooden Simple has the updated extruder. It shouldnt be too difficult for you to load up the .stl in 123D and make the minor adjustments needed to get this to work for the older extruder. That and you'd be a hero for all of the users that have an older extruder!

Video is private! Also, flip the piece over the X axis for it to work on a Printrbot Jr. (v2) with the Alu extruder upgrade!

Just what I needed!! Thank you so much for sharing! Could you share slice settings, i.e. layer height, infill, etc? My first attempt yielded a very fragile piece and it exploded when I attempted to install. Oh and the video is private :(

the video is private