Joerg Torhoff’s $50 Rock Tumbler Amazingly Polishes Metal Composite 3D Printed Objects

The idea of 3D printing with metal composite filaments is an interesting one. In fact, these metal composites have been all the rage as of late as filament manufacturers try to keep up with the trends while also offering something unique to the market. One of the companies that has really led the way when it comes to these new metallic filaments is ColorFabb. Their line of such materials consists of BrassFill, BronzeFill and CopperFill, all of which bring the possibility of printing objects with metal-like properties to desktop 3D printer users.

For one 47-year-old German man, named Joerg Torhoff, he has been experiencing various forms of 3D printing for the past 5-6 years. Having purchased his first 3D printer back in January of 2014, he has continued experimenting with the technology from different technological standpoints. When he was introduced to the metallic filaments from ColorFabb, that’s when the ideas really began popping into his head.

“In the future I would love to test as many 3D printers and exotic filaments as possible,” Torhoff tells 3DPrint.com.

Torhoff wanted a way to polish objects that he 3D printed in the various metal materials, but realized that manual methods of doing so were too burdensome and time consuming. On top of that, the results were not exactly what he had had in mind either. So Torhoff first decided that he would purchase a rock tumbler to do the hard work for him. Unfortunately though, the only quality machines he could find were priced at around $270, and this wasn’t a price he was willing to pay.

“So I decided to create my own tumbler,” Torhoff tells us. “At first I had a look at what to use as the polishing drum and came across PVC pipe coupling in a hardware store. They were dirt cheap and nevertheless perfect for this project. So actually I designed the machine around the drum rather than designing a machine and looking for the drum after the design process.”

Fittingly, Torhoff’s rock tumbler, which was being constructed for the sole purpose of tumbling 3D printed parts, is built from many 3D printed parts itself. In fact, the frame, as well as the two gear wheels and four pulleys, are all 3D printed. As for the parts that were sourced elsewhere, they include the motor, threaded rods, nuts, washers, and ball bearings, as well as the drum.

Parts that were tumbled in the Rock Tumbler

Torhoff tells us that the total cost to build his machine was a mere $44, although some of the parts he used were items that he already had in his possession. However, he says that anyone could recreate his machine for around $50-55 if these chose. As for its performance, he tells us it works like a charm.

“The tumbler performs very well,” he explained. “My first tumbler has now a running time of approx. 500+ hours without a single problem. It works 24+ hours in one go without the motor getting more than lukewarm. The best performance is achieved when using brass screws as polishing media. The decagon shaped inset makes sure that the parts and polishing media are well tumbled. I also tested some different transmission systems like regular gear wheels and GT Pulleys and belts, but in the end the herringbone gear wheels performed best.”

Prior to being tumbled

As you can see in the photos provided, the tumbler does an excellent job at polishing Torhoff’s ColorFabb 3D printed parts. What do you think of this creation? Discuss in the DIY Rock Tumbler forum thread on 3DPB.com. Check out some more photos below.