3D Printed Soprano Ukulele

I decided to create a design for a headless soprano ukulele.  I broke the design into three main pieces; the neck, the body and a piece to help stabilize the connection between the neck and body. I’d really like it to just be snap together but right now the parts need to be glued. I added a grid support to the front face of the body and I think it gives it a little bit of a pineapple/ukulele look. It plays pretty well but tuning it with the friction fit tuning pegs is irritating.  You can get the  part files and instructions for putting it together at Thingiverse.

My future plans for it are:

  • Add a back to it. It sounds pretty good without a back but maybe it’ll sound a little more ukulele-like and a little less banjo-like with a back on it.
  • I want to get rid of the friction fit tuning pegs. I want to put some nice (and hidden) tuning gears inside the body.
  • A better connection between the neck and the body with possibly a way to adjust the action.
Posted in Printed Objects

Masterbatch Ratios for the Filastruder

I’ve been mixing up different colors and running them through the Filastruder. I’ve kept the Filastruder going 100% of the time. I’m trying to do them in an order so that the colors are similar and that one batch can quickly transition to the next. Here is what I’ve done so far.

Lemon/Lime (1:64 master batch ratio) – The color came out very close to a nice lemon lime color. The color varied back and forth between green and yellow as it would hit one of the master batch granules.

  • 2 cups ABS Natural from OSPrinting
  • 1.25 tsp yellow master batch
  • 0.25 tsp blue master batch

Yellow (1:32 master batch ratio) – I wanted a color that could be used to print a Pikachu for my daughter. For a true Pikachu yellow, I probably should have added a tiny bit of red to it. The yellow came out nice although I’d like it to be a little darker and richer.

  • 2 cups ABS Natural from OSPrinting
  • 3 tsp yellow master batch

Orange ( 1:32 master batch ratio) – The orange came out almost like a traffic cone orange. And again, like the lemon/lime, the color varied between yellowish to reddish as it would hit a yellow or red granule.

  • 2 cups ABS Natural from OSPrinting
  • 1 tsp red master batch
  • 2 tsp yellow master batch

Red (1:64 master batch ratio) – I really wanted a fire engine red but this didn’t come close. It was a little light and pinkish. I think the problem is that I doubled the amount of ABS Natural when I was mixing it but forgot to double the master batch too.

  • 4 cups ABS Natural from OSPrinting
  • 3 tsp red master batch

Purple (1:32 master batch ratio) – I wanted a grape color but this came out too blue and too dark. The color was much more consistent than the others even though it was a mixture of two different master batch colors. I think that was because the blue color is a lot more dense and dominates the mixture. Next time, I’ll try more red and less blue.

  • 2 cups ABS Natural from OSPrinting
  • 1.5 tsp red master batch
  • 1.5 tsp blue master batch

Blue (1:32 master batch ratio) – The blue came out very nice. It was a bright almost electric blue. It has a variation to the blue that reminds me of the ocean.

  • 2 cups ABS Natural from OSPrinting
  • 3 tsp blue master batch

Green (1:32 master batch ratio) – This was the last of my ABS pellets from OSPrinting so I only made a cup worth. The green came out mostly dark with some variation from yellowish to forest green.

  • 1 cup ABS Natural from OSPrinting
  • 0.5 tsp blue master batch
  • 1 tsp yellow master match

Red (1:32 master batch ratio) – I was again trying for a fire engine red so this time I made sure that I made it at a 1:32 master batch ratio. I was also out of ABS from OSPrinting and used from pellets that I bought off eBay from carlsievering.  This was the first time I’ve used the pellets and I don’t know much about them but they are white-ish and not natural color so I guess that means they have white pigment already added to them. I think we know what happens when you mix white and red.  What came out of the Filastruder was much more pink than the previous batch of red. It’s a kind-of chewed bubble gum color. I didn’t time it but I think the Filastruder was also at least a third as fast in extruding them. Its been churning on the 2 cups of pellets for about 26 hours and it probably has several hours left to go. The filament is very flexible and I can bend it in much sharper angles than the OSPrinting filament which seems much more brittle . I wonder how well it’s going to print?

  • 2 cups ABS Natural from carlsievering
  • 3 tsp red master batch (from OSPrinting)

The colors that ended up with a variation to them were nice but if you are wanting solid colors, then these master batch granules are not quite the right size. They probably need to be at least a quarter of their size in order to disperse the color more evenly.

Update: I made another batch of red but this time I used a 1:24 ratio (2 cups of OSPrinting ABS pellets and 4 tsp red master batch).  The red came out almost perfect although I think it could be a little bit more intense. 

Posted in Filastruder

Converting my Filastruder to Vertical

After seeing this on Thingiverse, I gave it a try by just turning my Filastruder on it’s end.  After running it for a few minutes, it was an obviously better way to extrude filament. I decided to switch to a vertical Filastruder but there was no way I was going to take the pipe apart for a 3rd (4th?) time and risk messing up the thermistor to switch to a vertical hopper. I needed to design my own hopper that could be attached to the pipe without taking the extruder apart. Here’s my first shot at it.


That’s my smoke alarm right next to it. I wasn’t really worried that it would catch on fire. It was mostly just a good place to mount both of them in the workshop.


And here is a better view of the bolt-on hopper. Near the end of printing the hopper, it started slowly falling to the side  and that’s what is causing the little curve at the top of it.

You’ll also notice there is some tape at the bottom of it right next to the fins. As it was running, the auger was jamming the pellets into the bottom edge. That was forcing it out a little at the bottom and pellets were leaking. I’ll definitely be redesigning that part of the hopper.

Vertical is definitely the way to go. The filament comes out perfectly as long as you don’t touch it at any point from the nozzle to where it touches the floor. And it actually coils itself up pretty well and doesn’t end up as the tangled mess you’d expect.


Tagged with: , ,
Posted in Filastruder

Mixing Masterbatch for the Filastruder

For my first custom color filament on the Filastruder, I decided to do a key lime. This was mainly because I had some color shifting key-lime pie pigment left over from another project that I wanted to try. I’d also ordered a bunch of masterbatch pigments from OSPrinting. Here is the formula I used:

Key-Lime Pie

  • ABS Natural (2 cups)
  • ABS masterbatch @ 32:1
    • 85% Yellow (2.5 teaspoon)
    • 15% Blue (0.5 teaspoon)
  • Paint with Pearl – Key-Lime-Pie @ 96:1 (1 teaspoon)


This is mostly showing the filament that was created at the beginning. All that yellow came out before it hit the first green granule. The color still wasn’t solid but it looked a lot less yellow.

We’ll have to see how well this prints but I think the size of the granules isn’t small enough to disperse the color when the ratio gets really low. The blue component  in this color is at a ratio of about 1 in 192. First of all, it is hard to measure a consistent 1/2 teaspoon amount of masterbatch. And since the ganules are so big the extruder might only encounter a single blue granule every 10 or 20 feet of filament.  I suspect the smallest ratio of masterbatch color to use is probably about 1 in 100. But it might work out after the 3D printer’s effector mixes the plastic up a little more.

Here are the first two prints with the filament.  I tried picking something to be used outside in the sun to see how the color changing flakes would react. This is an adapter that screws onto a 2 liter plastic bottom and turns it into a water rocket.  The color changing additive doesn’t seem to be visible at all or at least it’s very subtle. I’ll probably try making this color filament again to see if I can tell any difference.

Update: I should have done this first but I just extruded some plain ABS and printed with it and the quality of the print was much better than this custom color. I don’t recommend mixing in the “Paint with Pearl” additive with the ABS plastic. The color-changing doesn’t work, you have to print it hotter and the plastic is much more brittle. I’m still going to try to do Key-Lime Pie again but I’ll just use the masterbatch pigments. 

Tagged with: , ,
Posted in Filastruder

Updated Magnetic Effector

Here is an update to the magnetic effector. I’ve tilted the fans and created some tunnels that direct the output of the three fans right at center of spot being printed. It still has room on the bottom for 3 strips of 6 LEDs.

I struggled to print it with 100% infill but was never successful without a lot of warping and curling. So I backed off on the infill. The settings for this print were 4 shells, 20% infill,  0.25mm layers, and 0.6mm skin.  The only problem I had was a slight curl on two of the  triangle tips.

I started off with white ABS and then switched to black at about 2mm.


Then near the end I decided to switch again for printing the fan tubes. I currently only have three colors in ABS so I switched to green.


IMG_2354 IMG_2355 IMG_2356

Unfortunately after all this, I discovered the screw mounts for the fans don’t work too well. I’ll need to do a little more work on the design and print it out again.

Tagged with:
Posted in Rostock Max Mods

Filastruder filament maker for 3D Printers

I received the Filastruder kit after backing it on Kickstarter. I was interested in it because I wanted to print lots of things and lots of big things.  My 3D printer is a Rostock Max and it has a pretty big build envelope so I didn’t want to limit my imagination by how much filament cost. The Filastruder box arrived on time but a little damaged and with a hole in it but luckily nothing was missing.

It didn’t take too long to put it together. I had preprinted all the plastic parts it needed so all the mechanics, including cutting a couple pieces of wood and painting them took about an hour and a half. The electronics took about another 45 minutes.


I wrapped the middle of the pipe with silicon tape but later thought about it some more and realized I probably want that section of pipe to be cooler instead of hotter so that the plastic doesn’t start melting too soon.


I also added some aluminum fins to help cool down the pipe.

I cranked it up and after about 5 feet of filament, it started to slow to a crawl until it finally stopped. After a few quick back-and-forth emails with Tim Elmore (the creator of Filastruder), it turns out I’d put one of the flanges on backward based on an older version of the instructions.

After taking the iron pipes off and switching the flange around, it extruded just fine. I ran it for a few hours to get any contaminates out of it.

Speed?  I ran 2 cups of ABS pellets though it, which is about 1/3 kg, and it took 10 hours.

Consistency? The filament diameter doesn’t vary as long as you don’t do or change anything while it is running. It shouldn’t be moved and the temperature shouldn’t be changed. Not changing anything also includes touching the filament coming out of the nozzle or even touching any part of the filament that causes the filament near the nozzle to move. Even small touches usually cause a little kink in the filament.

Tagged with: , ,
Posted in Filastruder

Magnetic Effector for the Rostock Max

I’ve been experimenting for the last month or so with creating my own version of the magnetic arms for the Rostock Max printer. I started with a few goals.

  • Print as many of the parts as possible.
  • Incorporate part and PEEK fans.
  • Add support for LED strips.
  • Help manage all the wires going to the hot end.
  • No firmware changes.
  • Any hardware changes can be easily reversed.

Initially I wanted to use magnets on both sides of the chrome balls. The effector had holes in it to place the magnets and so did the connection plates. So that means I was printing the mounts for the chrome balls instead of gluing them to screws that are then screwed into effector and connection plates. I’ll show the general progress of the effector design while skipping over all the smaller tweaks and printing/warping/curling issues.

IMG_2300 IMG_2297

You can also see the squares for mounting some 25mm fans. The magnets bothered the fans a lot in these locations and I could never get enough of a magnetic attraction along with the range of motion needed with the magnets stuck inside the effector. So I decided to try gluing the chrome balls to the effector instead.


Here I also moved the fan holes to a spot in-between the ball mounts. With the next itteration I moved the part fans a little further out and indented them into the surface of the effector.


And here it is with the balls and fake fans in place.


The mounts for the chrome balls were a lot fatter than they needed and limited the range-of-motion for big prints so I made them a little skinnier in the next version.

I also experimented with printing the effector in two different colors. I wanted to put white on the bottom to help reflect the light from the LEDs so I’d start out the print in white and then after a few layers, pause the print and put in black. Here are a couple versions of the idea. You could control how bright the white was by how many layers were printed. The black really wanted to show through and you ended up needing at least 6 layers to cover up the black.


I kept on getting slight curling and warping problems with ABS so I switched to PLA and was able to get a good unwarped print of the effector.


This one is all assembled and I was printing with it for a few days. Unfortunately I discovered that  PLA isn’t appropriate for an effector. It isn’t because the hot end gets too hot. I don’t think the hot end heat is much of a problem, especially with the PEEK fan blowing. The problem is the heated bed. The large surface area of the effector hovering over the heated bed soaks up all the heat and after printing for a while, it starts waving like a flag as the arms push and pull on it.

Here’s the bottom showing the LED strips. I made it so I could put two sets of 3 LEDs on each side.


I used this effector to print a nylon one and that is where I’m at now.


It stands up to the heat well but probably isn’t ridged enough. The bottom of it also got a little torn up when I tried removing it from the grid I printed it on. And YES!, those chrome balls are superglued to nylon. It can be done. I just scuffed up the ball a little, put the ball in the indention with some glue and put a clamp on it for a few hours. I haven’t had any come loose while printing so far.  The magnetic attraction will probably fail much sooner than the glue will. Even though, I’ll probably try printing in ABS for the next iteration.




You can get the latest version of it from Thingiverse.

Posted in Rostock Max Mods