Water Marbling 3D Prints

3D printing opens the door to many other forms of creative fabrication and helps us to learn new and interesting talents. These instructions teach how to use a process called water marbling to add a new and creative finishing technique to your 3D prints.


  • A 5 gallon bucket (It will get paint on it so make sure it’s not important)
  • Spray paint – In at least two different colors
  • Fishing line
  • Water
  • Rubber gloves


Note: Read through the steps a few times carefully before starting because some of the steps are time sensitive.

  1. First, select the print that you want to add a marbling design to. When selecting your print, keep in mind that the base color can alter the effect of the marbling. This effect is good look for a lighter-colored print like white or yellow. Darker colors, even black, can work, but the effect by be less clear. It might also be helpful to add a hole somewhere on the design for a later step.
  2. Tie a piece of fishing line to your print to use as a dipping string. If you added a hole to your print earlier, you can use it for this step.
  3. Fill the bucket most of the way up with water, more than enough to completely submerge the print.
  4. Spray the first color of spray paint in the center of the water for about 3 seconds. This should form a puddle of paint that will sit on top of the water.
  5. Then spray the second color as close to center of the puddle from the first color as you can for the same amount of time. This will create a second color puddle surrounded by the first.
  6. Continue steps 4 & 5 between 5 to 8 times interchanging the colors as you go. This will form alternating rings of paint resting on the surface of the water.
  7. Drag an object (a pencil seems to work well) through the paint sitting on the water to begin mixing and marbling the paint. Move slowly and stir the rings until you like the design that forms. Make sure to do this as quick as you can because the paint will begin to dry.
  8. Once you like the design that’s on the water it is time to dip the print. Slowly submerge the print into the paint – making sure it is completely submerged. Depending on its shape the print may float, if it does be sure to push it down until it is completely submerged (use an object or gloves to completely submerge the print).
  9. Keep the print completely submerged for about a minute. This will give the paint time to dry under the water.
  10. While the print is still under water, use some paper towels to wipe the paint off of the surface of water. Be carful not to hit the print with the paper towels. Keep wiping the top of the water until most of the paint is gone. Wear your gloves to be sure to keep the paint off your hands during this process.
  11. Once you have cleared most of the paint away carefully remove the print from the water. The paint will not be fully dry yet, so avoid touching it or bumping it into anything.
  12. Hold the print in the air for about a minute and then set it somewhere to dry for 30 minutes

Multicolored 3D Printing with Sharpies

Multicolored 3D Printing with Sharpies

Tired of white filament? Want to help your youth personalize their 3D prints without having to swap rolls of filament?

We print in a lot of white filament at the Tech Center but that doesn’t mean we lack creativity. This simple little hack will have you printing in as many colors as you want without ever having to swap that roll of white filament out.

I was originally inspired by my friend Josh Ajima (you should be following him on Twitter) who wrote an article for Make Magazine called “Rainbow Extrusion: Coloring 3D Printer Filament.” In that article, Josh uses Sharpie markers to color lengths of filament to create fun multi-colored Make robots. It is super easy to do and it adds a touch of personalization to prints without the hassle of swapping filament.

I’m a big fan of the mantra, “work smarter, not harder” and the thought of manually coloring a meter or more of filament seemed like it could be improved upon. I’m not the only one who had that thought and I found a great design on Thingiverse for a marker holder for 3mm filament. Turns out, that design works just fine with 1.75mm PLA filament too without any modifications. Just print the holder, run your filament through it and into your extruder, and you are done. Add markers as desired.

As the filament is pulled through the marker holder, the filament is colored for you by the marker. You can leave the marker holder on top of your printer and it shouldn’t affect the flow of filament.

For best results, always use two similar colors in the marker holder. You will also have to push the markers pretty far in or drill out the holes a little so the markers press against the filament.

With white filament, the markers come out more pastel, or milky, in tone. With transparent or natural filament, it will come out looking closer to the color of a gel pen with more of a glossy sheen as seen in the photo above.

This is an easy way to allow your youth to personalize their prints. I’ve also found that they have a stronger feeling ownership of the end product. It also allows you to have multiple colors without having to buy multiple rolls of filament, just an 8-pack of Sharpies (or two).

First Layer Problems: Solved

The first layer of a 3D print is one of the most important. It sets the stage for the rest of the print. I relate it to the old adage questionably attributed to Abraham Lincoln, “If I had 5 minutes to cut down a tree, I would use two-and-a-half minutes to sharpen my axe.” I have been known to spend two hours or more calibrating that first layer of a printer to make sure that the results are repeatable and reliable for as many prints as possible.

If your Z height is not calibrated perfectly (or within a certain margin of error), there are two main problems that can occur:

Problem #1: First Layer Too High

First Layer Too High

If your first layer is too high, your print will not stick to the bed properly and will most likely pop off somewhere in the middle of printing, usually long enough in to the print time that you have stopped watching the printer but early enough to ensure a good amount of filament spaghetti or blob of filament on your hot end.

Filament Spaghetti

Problem #2: First Layer Too Low

First Layer Too Low

If your first layer is too low, your hot end will drag through each previous layer. This not only creates an unsightly top layer but also will make your hot end prone to clogging very quickly. Additionally, your layers will be more smooshed, causing the filament to spread out to the sides of the nozzle and increasing the thickness of your designs, thus making fitted pieces very difficult to print.

BuildTak to the Rescue


I first saw BuildTak in a rather serendipitous way. Someone had just posted a new print of one of my designs on Thingiverse and I went on to check it out. On their build plate, below my printed design, was this strange black material where I expected to see blue tape or kapton tape. Fortunately for me, the label of the material was visible and I put my CSI “enhance” skills to work and was able to make out the words “BuildTak”. After some quick Googling, I found the material and started reading reviews. Everything I read was positive about the material so I decided to order some samples from Amazon to test on one of our Printrbot Metal Simples.

I had to cut a small strip off the sheet to make it fit on our bed and then I recalibrated the bed probe for the thickness of the sheet (it’s much thicker than blue tape or Kapton tape). We tested the new bed material during one of our field trips to the Tech Center and I was amazed how quickly we were able to pop the print off and start a new print without having to replace or repair blue tape. It was shaving a minute off of our print transition times (which is a big deal when you have 25 keychains to print in 90 minutes or less) and we were getting even more reliable prints than our printers with blue tape. Additionally, there were no bits of blue tape stuck to the bottom of the prints.

After the first two days of testing, I was convinced and I ordered enough BuildTak for all of our printers. You can get it from Amazon and I was getting 3 sheets for roughly $25. In theory, BuildTak will wear out and need replacing. I’ve heard somewhere over 100 prints is when it will need replacing. At this point, we are just about at 150 prints on the first printer I tested the BuildTak on and I don’t see a need to replace it. I’ll update this blog post when we do replace our first piece.

BuildTak does a great job of grabbing that first layer of filament and holding on to it. Even if your settings aren’t perfectly calibrated, chances are your print will still come off great. Plus, you get the added bonus of not having to re-tape every 10 prints or so. The material gives you more room for error on your first layer settings and you get better prints even if your settings aren’t dialed in to the micrometer.

PB Simple Army

In short, I’ve been really impressed with how much easier BuildTak makes it to get a good first layer.  It gives you a much larger buffer for your “perfect” Z height and lasts longer than blue tape.

Update #1:

We replaced our first piece of worn out BuildTak after 1,277 prints.

I did some fun math to see how BuildTak compares to blue painters tape in terms of costs:

BuildTak roughly costs $9.61 per sheet. At 1,277 prints, that’s a price of $0.0075 per print.

Blue painters tape is roughly $14.65 for 60yds x 2″. I estimated that I can get 800 prints per roll of painters tape, that’s a price of $0.0183 per print.

Pretty small costs all around but I also think BuildTak saves time compared to blue tape.