Recycling 3D Printing - Colored Plastic Sheets for Laser Cutting!

Smash > Blend > Bake > Cut>Finish
Anyone that uses 3D printing gets to a point where they wonder if it’s possible to recycle their unsuccessful projects, pieces of study or support material. A year ago I saw a YouTube video of Make Anything recycling printsand making plates to try to cut them manually or mold them into pots. I did this once at home with a friend of mine (Fabio Iori), but never really used the plates for anything. Since my college’s MakerLab has a very large amount of leftover material, I decided to do a little experiment! Except that, this time, I made some adjustments to the previous process and laser cut the plate to use it as signaling for our space.

I would like to leave a special thank you to my friends Leonardo Trevisa, Rafael Coelho e Iago Rodrigues that gladly helped me to smash and break into tiny pieces the useless prints. My friend Victor Damiani, for taking some pictures of the process, and Fabio Iori, for the correction of the written part.

For Smashing

- Old or Failed prints

- Plastic Bag

- Hammer

- Anvil (If you prefer)

For Blending

- A not-for-food blender

- Tape For Baking - A not-for-food oven

- A not-for-food pan (it's important that the pans fit together. Different sized ones can work better)

- Something heavy that will not catch fire

For Engraving and Cutting

- A Laser Cuter

- RDWorksV8 (Software)

- Adobe Illustrator (Software)

For Finishing

- Automotive Ink PU HS + Hardener (Wanda Amarelo Speed in this case)

- Sand paper A180

- Acetone (If you prefer)

Before placing the pieces into the blender, you will need to smash them into smaller ones to avoid any damage to the equipment.
The PLA usually flies everywhere when you crush it, so it's important to wear goggles! Using plastic sachets to wrap the pieces can help to contain the shrapnel, making the cleaning process easier and ensuring more safety.

If you prefer, or do not want to sacrifice a liquid-blender, you can put the crushed pieces straight into the oven, if you do not mind a rougher look.

Now it’s time to put the small pieces into the blender. Keep in mind that there’s the possibility that your blender may not survive this stage. Ours went through some malfunctions during the development of this step, but remains strong as I’m writing. If the glass container of your blender cracks, like ours did, you should pass a ribbon over it to prevent larger leaks.
Start slowly putting the pieces of plastic. A bit of water helps the crushing. Long strips tend to curl on the blades, so it’s best to cut it into smaller pieces.

Leave the blender on until you have more uniform sized pieces. The PLA tends to look like gravel since ABS stays in small strips, like fibers. In our case, we left PLA mixed with ABS.

Time to bake your plastic plate! To do this, distribute the plastic grains in the most uniform way possible. Try not to leave gaps or holes that could leave the plate inconsistent.
Use the different sized pans to make a sandwich with the plastic so you can achieve consistency on both sides. It is important that both pans are flat, because if the plate is ondulated the laser may not cut it.

We made the laser cutting design with Adobe Illustrator and then prepared it for cutting with RDWorksV8.
Our laser has 100W, however, we usually use its power from 78 to 80% for MDF 3MM, cutting at a speed of 16 mm/s. For notch, we use from 28 to 30% power at 110mm/s.

The plate we made had 10mm in its thickest part. For cutting, we did some tests and the cut was well done at a speed of 4mm/s with the power from 78 to 80%. The engrave was made with the power from 28 to 30% with the speed of 70mm/s.

Note that it is necessary to adjust the focus distance of your laser!

To finish my project, I thought it would be interesting to give a little more prominence to the engraved letters, so I chose to splash some color into it using automotive paint, as it would also fill the cavity.
This process required several coatings of paint as it kept infiltrating through the gaps of the plate. After a while, the ink itself sealed these holes - it was interesting to watch the paint sticking inside the plate.

If you haven’t used masking tape to protect your piece during the laser engraving, you will probably need to sand it to remove the excess of paint - I used an A180 sandpaper.

Doing this you will lose the shininess of the plate. To bring it back to its full shine glory, you can use a cloth moist with acetone and rub it lightly on the ABS - it comes out looking very interesting. If you want to brighten the entire plate, simply apply a layer of varnish or place masking tape on the plate before engraving with the laser to protect it during painting.

Now just hang your super colorful and recycled board :)
Remember! For this it is better to glue a bracket behind the board with super glue because screws tend not to work. If you enjoyed, please favorite my project!

You can message me if any question pops up :D