Producing a perfectly shaped wooden sphere without machine assistance is almost impossible. Industrial sphere machines are extremely expensive and far too bulky for home use. For this reason, I designed, built and tested a 3D-printed ball machine. The machine is comparatively simple in design and should be able to be assembled by anyone who can hold a screwdriver.
Wooden balls are not only aesthetically pleasing, but also make excellent decorative elements in various rooms. They can be used to make candle holders, scented balls and much more.
The 3D printing
The 3D printing process should run smoothly as the parts are designed to be printed without support structures. The machine can be printed from PLA/PETG or ABS, with no special requirements for the material. An infill of about 30% is recommended, as considerable forces and vibrations occur on the machine, especially at the beginning when the sphere is not yet very round.
I printed the Sphere machine with a Creality Ender-3 V2 KE. This is a high-speed printer in the lower price segment that packs a punch. It has the Klipper firmware which makes it possible to run a web server on it. This is a really useful feature that allows you to monitor and control the printer from the comfort of your sofa. It also has fully automatic bed leveling with a CR touch sensor. Bed leveling is one of the best features of the printer, as it completely eliminates the hassle of adjusting the print bed. Before printing starts, the nozzle is cleaned so that it is always clean. All these points really make 3D printing extremely easy and carefree.
If you want to find out more about this printer, take a look at my review of it. Here you can buy the printer for under 300€:
Creality Ender-3 V3 KE / Code: NNNDEV3KE
The assembly
Assembly is very simple. Some parts need to be fitted with threaded fusion nuts, which can easily be done with a soldering tool. Some M6 and M4 threaded rods need to be cut to connect the parts. The best way to do this is to watch my video, then the assembly should be clear, I think.
To sand a sphere, you need a piece of wood that already has the rough shape of a sphere. The better and more precise you work here, the faster the sanding process with the Sphere machine will be. It is advisable to allow some time for this preparatory work. 10 minutes of additional work at the beginning can save about an hour of sanding work with the machine. The more accurate the basic shape of the sphere is, the less the machine will vibrate later.
A piece of sandpaper is now clamped into all three sanding blocks. The sandpaper is held firmly in place using a clamping ring and a screw. The correct technique for clamping the sandpaper is particularly important with coarse sandpaper, which is used for rough sanding at the beginning. An effective trick is to cut a wedge out of the center of the sandpaper. The corners are then cut in so that the sandpaper can lay neatly in the hollow sanding block.
For the first rough sanding job, I would recommend using two pieces of sanding blocks with coarse sandpaper and a can drill. The great thing about the can drill bits is that you can use different sizes. Commercially available can drills are available with a round 8mm hole or a hexagonal hole. The best part is that the motors have an 8mm shaft, making them perfect for clamping a can drill. If your drill has a hexagonal hole, that’s no problem. It is very easy to drill out to an 8mm hole.
Another effective way to create a sphere without a lot of dust and dirt from the rough sanding process is to cut individual layers with a desktop laser and then glue them together in layers. By using different types of wood, very beautiful patterned baubles can be produced. I prefer this method as it is extremely simple and gives really excellent results.
The sanding process takes a few hours, but your patience is rewarded with perfectly shaped wooden balls. It is great fun to watch how the balls become more and more beautiful and smooth as the sandpaper gets finer and finer. Finally, the balls can be coated with a wood stain to create the perfect shine.
You can download the building plan here:
You will get the following digital files:
- All .stl files you need to print the machine.
- Assembly drawing in .pdf, .dxf -format.
- The complete 3D model of the machine in .step – format.
- A detailed parts list of all installed parts including internet links to the supplier.
- An instruction video with all building steps.
- I will do my best to help you with any problems or questions.
- A template in .dxf format for the laser (D=80mm)
