Custom Concrete Lamp

This unique RGB lamp has been modeled in Fusion 360 with the intentions of being completely customizable. Cast from a 3D printed mold, this concrete design becomes a striking feature in any room. Thanks to its parametric functionality, this lamp can be quickly scaled to suit any needs. Ultimately, in just a few simple virtual steps, the entire illuminated pattern can be modified to create a one-of-a-kind piece of art!

• Resin printer – Elegoo Mars 2 Pro
• Clear resin – Using Siraya Tech Simple resin for this project
• FDM printer – Ender 3 Pro and CR10 printers
• PLA is recommended for this project due to its low melting temperature
• Hot glue – To temporarily secure parts for mold assembly
• Heat gun – To heat all thermoplastics to aid the demolding process
• Concreate/Cement – Used Quickcreate due to fine consistency and non-shrinking characteristics to be safe when testing. Some bags of concrete with larger rocks can be sifted through if needed.
• Wood Veneer – Decorative material to contrast the concrete and enhance the base appearance

• Lighting – Lighting can be easily altered depending on user preferences. This featured design combines the power of a esp8266 D1 mini with a 24 pixel LED light ring. The base is designed to receive power through a round DC power jack socket

The mold is designed to be printed, assembled, and disassemble with little to no hassle. The assembly is comprised of the following four main components: outer shell, inner core, core lid, and base. Additional outer ribbing is available to provide increased support to the outer shell. It was observed in testing that the difference in force applied by the ribs could cause some differences in the texture of the outer finish of the concrete.

The dimensions of the outer shell can be modified to work with Cura slicer's vase mode. This method works well with smaller designs, but the forces exerted by the larger models tend to require additional thickness. Thinner wall designs should be reinforced with tape to minimize layer splitting during the pour.

The inner core is comprised of the inner shell and lid. Since it will ultimately be under the pour, vase mode is not advised for these pieces.

The inner and outer shells are designed to have an additional material layer in between them and the pour to create a better surface finish and provide more rigidity while minimizing print time. This will allow much faster shell prints using vase mode while also providing the extra durability required. House flashing would be an ideal fit for this application.

Both walls of the mold shell are to be secured to the mold base. This will keep the bottom diameter precise and centered for the base of our lamp. Additionally, to ensure a perfectly round cylindrical pour, the top rib can be combined to the outer shell to create a thicker lip at the top of the mold to prevent the cement from warping.

The 3D printed 'windows' allow the light to escape through elaborately designed shapes. For this example, a series of squiggles was chosen for the design.

Since the printed parts will be sandwiched between the mold shells, it is important to get a snug fit to prevent the cement from seeping in between. Prioritizing supports along the sides of the parts will achieve a nicer finish on the top and bottom surfaces and subsequently provide a better fit with the mold.

As an alternative to resin printing, simple opaque PLA can be substituted and removed with the rest of the mold, leaving precise gaps in the concrete for the light to escape.

It is super easy to create your own custom window designs!

The custom design is imported into Fusion 360 as an SVG. SVGs can be created in many popular drawing programs, such as Illustrator or Inkscape.

Start by finding the desired circumference of the design. This can be done using the measure feature in Fusion 360 or calculated with the simple math equation 2*PI*r. The parameter titled 'WrapCircumference' already does this calculation for you! Using the circumference as width coupled with the pour height, create a canvas whose dimensions match the outer surface of the model. This canvas acts as an unwrapped view of the cylindrical pour. Once it is imported into CAD, it will be wrapped around the model to create the custom designs.

On the canvas, create a vector pattern leaving ample room in between the pieces for concrete to flow. To minimize the risk of air gaps forming, it is best to avoid concave designs allowing pour to fill naturally. Remember to also allocate room at the top of the design for the ceiling of the pour. Any designs overlapping the ceiling region will not have direct access to the light source in the inner core. To simplify dimensions, the ceiling thickness is the same as the wall thickness.

Once the custom design is complete, export the canvas as an SVG. In Fusion 360, there are two main sketches labeled ProjectionGrid, and ProjectionSVG. ProjectionGrid displays the canvas size and ceiling height. This can be utilized to properly align the SVG. The ProjectionSVG sketch is the intended import location for the custom canvas. While editing the sketch, delete all preexisting entities and insert the SVG. The Fusion 360 software has an interesting DPI difference that will most likely require the imported item to be scaled. For most programs, a scaling factor of 1.33 should fix any issues.

Once everything is imported and aligned, the emboss feature, found in the timeline, can be modified to adjust the sketch profiles to complement the new design.

Prefer creating your own custom design directly in Fusion360? Want to dramatically simplify the process? Design your own customs drawings within the ProjectionSVG sketch using the ProjectionGrid as a guideline.

The intended final result of the mold assembly is to have the resin 'windows' perfectly sandwiched between the inner and outer shells.

Referencing the 3D model, start by securing the windows to the inner core using a fine layer of hot glue. Thanks to the characteristics of the cylinder, the curved shape of each 'window' will help orient the rotation of each piece. Printing out the SVG design to use as a stencil will help further perfect the horizontal and vertical positioning. The hot glue acts as a temporary hold that additionally helps prevent any of the pour from seeping behind the 'windows'.

Once the 'windows' are properly positioned, press fit the inner core with attached windows onto the base, capping it with the core lid. If the friction fit between the pieces is not very secure, apply additional hot glue to achieve the desired result.

Finally, slide the outer core gently over the windows until properly seated in the base. Secure with a bead of hot glue as needed.

Once the concrete mix has has reached the desired consistency, slowly pour into the mold. For best results, place the mold on a flat surface. When pouring, aim for the top of the lid allowing the material to flow into the lower sections without accidentally disturbing any pieces of the assembly. When casting molds with any material, it is extremely common for air bubbles to become trapped. Vibrating or gently bumping the print will help the trapped air escape allowing the concrete to find the deep crevices. Slightly overfilling the mold accounts for any settling that might occur during the initial part of the curing process. It will also help create the squared edge finish.

Since no one can resist touching a drying surface, it is beneficial to pour extra concrete into a paper bowl to create a sample piece that can be used to monitor the consistency and curing process.

Once the concrete starts to solidify, level off the top of the pour using a trowel or straight edge, leaving a smooth top surface.

Following the manufacturer’s instructions, let the cast sit for the required cure time before beginning the demolding process.

Once the cast has properly hardened, the mold can be removed. First, using an applied force, remove the base from the rest of the mold assembly to gain unrestricted access. Since the mold is solely comprised of thermoplastics, a heat source will easily soften the pieces for removal. With the assistance of a heat gun, peel off the mold shells and remove the lid from the pour. Any flashing from the mold will be thin enough to break off without leaving noticeable damage.

If using thermoplastics as a part of the final piece, such as creating windows with transparent PLA, applied heat is not recommended. Most printed plastics will be brittle enough to slowly break away from the pour, leaving the rest of the project unharmed.

The base is comprised of two main 3D printed features. The actual base 'ring' supports the concrete pour while the lighting frame houses the electronic components. The base design is cosmetically very simple to keep the scope of the project focused on the concrete. This simple design also allows for mixing and matching different parts to create new combinations. The base ring has an inner raised edge to center the pour and six mounting slots to attach the lighting frame.

The base is 3D printed with PLA plastic with the infill adjusted to account for supporting the entire concrete structure. For this example, the base parameters are modified to allow the addition of a veneer outer surface. A different design aesthetic can be achieved by substituting the veneer with a coat of paint.

With a heat gun, preheat the veneer glue. Avoid heating the 3D printed base to prevent any melting. Once the glue is viscous, slowly wrap the veneer around the base. Apply minimal heat when necessary. Once the base wrapping is nearing completion, trim the veneer so that the ends meet seamlessly. Once the glue has solidified, trim and sand any protruding edges. Using a craft knife, remove any material covering the electronics bore hole on the back of the print.

Thanks to the modular basis of this design, a plethora of lighting components can be used to bring this project to life.

A microcontroller paired with addressable LEDs maximizes the lamp's ability, allowing for a wide array of different colors and animation sequences.

The lighting frame featured in this 3D design is designed to parametrically accommodate an addressable LED ring and microcontroller. Just like the rest of the components, this frame is intended to be modified or replaced to comply with any reasonable lighting methods.

Using the hot glue, fix the electronic components to the frame and connect the wiring according to the wiring schematic. Secure the frame to the base using screws specified in the parametric design. Lastly, press fit the DC power jack into the electronics bore on the base and connect to the power input pins.

Unfortunately, the final assembly will be the most complex and daunting part of the entire project.

Place the molded concrete piece onto the assembled base. Provide power to the microcontroller utilizing the DC jack.

And now you are ready to create your own awesome designs!

Attached below is the parametric Fusion 360 file used throughout this Instructables.

I can't wait to see what you come up with!