3D Printing with NinjaFlex Filament

Not all 3D printing filament is created the same. We all know about PLA and ABS...both create rigid plastic pieces. But in October of 2013, a company called Fenner Drives launched NinjaFlex. It's very flexible and works on 3D printers with direct-drive extruders.  

To use NinjaFlex you have to play around with the settings a bit but, so after a little online research and a few changes in various settings, I think we are almost where we need to be. It took a few hours of adjusting and printing, the results were pretty good.

The first thing we had to do was print a "filament guide" piece for our Printrbot Simple Metal. Without it, the softer filament would bunch up before it even got to the extruder.

The first problem was that the design must be for an older version or our printer because the bottom "bridge" piece would not go over the "hump" where the filament enters the extruder.

So I had to brake it off and see if that would work. It fit and then it was time to adjust the tension. Getting the right about of pressure took a little time. Too loose and the filament wouldn't be pushed through the extruder, too tight and it would start to bunch up around the wheels.

Finally the pressure was correct and we started to print. I started out with the suggested settings from the NinjaFlex website (http://www.ninjaflex3d.com/). It worked OK but as I did more research, I realized that different people used different settings...sometimes for the same machines.

Five different settings and 5 different caps. The best one (the one on the far right) was the most consistent print with the least amount of "whiskers" (it had a travel speed of 100mm). I realized that lower the "travel" time the more "whiskers" you got. I have a few more test to run, but it seems like it's going to be somewhere between 100mm and 130mm. At the end of this post, I'll have all the settings I am using.

Printing the caps was fairly simple, so I tried printing a castle next. The next 3 pictures are of the castle with the slow travel speed of 45mm. As you can see, lots of "whiskers".

The next printing was with a travel speed of 130mm. I still got whiskers but not as many.

The castle with the slow travel time is on the left and the faster travel time is on the right. You can even see the door on the right one...the left castle's is filled in.

The next step is to reduce the speed back to 100, print the castle again and see if that improves things. Depending on the outcome of that print, I might try 115mm...split the difference and see what that does.

I figured I would try a different print so I did this one...as you can see, it could use a little support material at the bottom (on both sides) but it didn't turn out too bad.

Here are screen shots of the settings I am using. If you fine tune them, please let me know...I'd love to hear what you did.

6th Graders & littleBits

In their science class, our 6th graders have been learning about electricity. As students finish the assignments in the science lab, they are released to come to the FabLab to "play" with littleBits. We have the whole Pro Library but I have only put out a handful of modules for them to start working with. As time goes on, we'll increase the number of pieces they will have access to.

Moving the Room Around

The nice thing about tables with wheels is that we can configure the Lab any way we need. I have classes coming in for group lessons so I rearranged the tables, giving everyone has a good view of the SmartBoard.

More teacher made stuff

I needed to secure our LittleBits Library boards to our pegboard. I took some measurements, sketched some ideas and created a bracket that I thought would work. It took 4 different improvements, but what I came up with works great.

This was the final design. Our peg boards have foam in between each side of the board, so to make the bracket a little more secure I made a small physical alteration. I took a utility knife and made "barbs" along the edges. It gave the peg part a little more "bite" to the plastic.

Family Heritage Boxes with 2nd Grade

In the 4th grade social studies classes, our students have been learning about family heritage. Part of their research involved interviewing their parents and grandparents.

The teachers wanted to make some type of project using the engineering design process and design thinking. We came up with the idea of making a box that the students could personalize and take home at the end of the unit.

As part of the interview, the students asked the adults to think about a symbol that would represent a part of their parent's and grandparent's life. The students picked 3 symbols and made a 2x2 inch pencil drawings of each one.

Then in the Lab, we scanned each symbol, cut & pasted them to an Inkscape template and laser cut the box pieces. The students glued the boxes together and had a great keepsake to take home.