ToyRep 3D Printer – Costs Under $85 to Build Using Super Cheap 28BYJ-48 Motors

When I first began covering the 3D printing space a couple years ago, the first thing I thought was, “Boy this technology will change the world”. That thought, however, was followed by a big “IF” –“if prices for home use ever fall”.

At the time, I was thinking that perhaps in another 5-10 years we would see desktop 3D printers reach a more “realistic” price point. To my surprise though, this has already begun to happen. We’ve since seen numerous 3D printers come to market, priced under the $400 mark. At the same time, innovators from around the world, thanks to open source movements like RepRap, have been able to come up with better ways of developing 3D printers, both to print in higher quality as well as significantly reduce their prices.

For one Czech architect, named Martin Hrib, he never really considered building his own 3D printer until he was tasked with helping a friend out with a project involving an affordable 28BYJ-48 stepper motor.

“I started to wonder if this stepper may be used in an inexpensive 3D printer too,” Hrib tells 3DPrint.com. “So I bought some motors, made a model of a Printrbot inspired RepRap and we started thinking about cheap electronics for unipolar stepper motors.”

Then a 16-year-old German teenager, named Johannes Rostek developed a $70 3D Printer, called the “Cherry Printer”, which used motors with a bipolar hack. This is when Hrib realized that a solution to developing an affordable printer, using cheap stepper motors was already out there. One thing led to another and Hrib decided to begin polishing his old concept with some new ideas that he had learned and read about. This is when he came up with a proof of concept for his ToyRep 3D Printer. After sharing his design with the RepRap community he was surprised by all of the positive feedback. Perhaps it’s because of the printer’s simplicity but more likely because of its extremely affordable price to build.

“As per the BoM sheet, a brand new printer should cost around 100EUR including duty and taxes,” Hrib tells us. “If these taxes do not apply to your country, you manage to get some stuff on sale, or have leftovers of rods like me, then it may be cheaper. I think my machine was created for around 75 EUR at most.”

Usually when you think of cheap electronics, you think of poorly built machines which provide low quality results. This isn’t the case with the ToyRep though.

“The printer is extremely precise as it does 650 micro steps per mm in X and Y axis with 1/16 micro stepping,” Hrib explains. “My first Prusa Mendel had 80 micro steps per mm just for the comparison. In the Z axis it has 40960 micro steps per mm! But all you gain on movement is a bit spoiled by cheap hotend and weak 28BYJ-48 driven extruder, that cannot do retraction quickly enough. So the results are quite close to the one of the other common Reprap you see.”

The printer can print about 12.5mm/s in the X and Y directions, because of the lower quality motors, and it utilizes a relatively small build volume of 100x100x100mm in order to help inhibit the motors from overheating. Hrib believes that the biggest advantage of his machine is the price, but also its ability for self replication and its compact/modular design. At the same time, it is very cheap to operate, costing very little for the electricity to power it

For those interested in building their own ToyRep, they can download the design files and see instructions on Thingiverse.

What do you think about the potential this cheap 3D printer has in bringing the technology to the masses? Discuss in the ToyRep forum thread on 3DPB.com. Check out the video below.