I like to make things,” says Karan Chaphekar. “Let’s make a ring…” The 22-yearold searches the internet for a 3D model, clicks a few commands on his computer and waits as his “homemade” printer squirts thin strings of plastic on a flat bed. Layer by layer, it constructs the Green Lantern superhero ring. Just watching the machine convert the virtual image into a physical object is awe-inspiring.
Chaphekar nonchalantly picks up the finished jewellery and studies it.
“Not bad, but this needs some improvement,” he says almost to himself, before pulling out a bag full of synthetic objects – including a little green cube, a collection of miniature sailing ships, an octopus paperweight and even the bust of Star Wars’ Yoda – all printed by his machine.
And while Chaphekar is not the first person in the world to build such a printer, his model – costing about Rs 40,000 – is one of the cheapest available.
His RepRap (replicating rapid prototyper) 3D printer is in a constant state of upgradation, he says.
“There’s a very active opensource developer community on the web that is constantly sharing information on how the RepRap, both hardware and software, can be improved,” he says.
Repping and Rapping
Simply put, the RepRap works exactly like a computer-controlled inkjet printer; only instead of ink, it uses plastic filaments that pass through a ‘hot-end nozzle’ meant to melt them into finer threads. These threads are “printed” on to a flat surface to create a solid object.
“To build a new object, you need a 3D softcopy of the design,” Chaphekar says. “Then, using software like Slic3r, you can send the file data to the printer in a coded language that it can read.”
The software slices the design into layers, using which, the 0.35mm-wide nozzle squirts melted plastic at 200 degrees Celsius to build the objects layer by layer.
“The 50x40x36-cm printer is small enough to fit on your desk and can print objects as large as 20x20x4 cms.”
“I use two types of plastics for my models, both of which I have imported from China. The first is a transparent plastic produced from cane sugar or glucose called PLA (Polylactic Acid) while the second is a sturdier form called ABS (Acrylonitrile Butadiene Styrene),” he says.
A Whole New Thingiverse
And like the reels, most parts of Chaphekar’s machine, have been imported from different countries.
“I picked up some of the parts from Lamington Road, the mecca of electronics in Mumbai; a few other important parts were sourced from Spain, and for the rest I relied on the goodwill of members from the RepRap community in the US and the UK who were kind enough to donate stuff to me.
“The aim is to build low-cost self-replicating machines. So the printer is actually capable of printing a clone of itself. I can make a brand new printer like this one in just 17 hours,” he says.
Given the open source project’s philosophy of ‘replication and evolution’, different generations of the RepRap printers have been named after biologists: [Charles] Darwin (2007), [Gregor Johann] Mendel (2009), Prusa Mendel (2010) and [Thomas Henry] Huxley (2010).
Chaphekar, whose printer is based on the Prusa Mendel design, has been a member of the community for six months now.
The idea is to replicate and help others build similar printers, he says.
“The cheaper it gets, the easier it will be for people to build them at home,” he adds, describing a trend that is being dubbed the Industrial Revolution 2.0.
Besides the open-source DIY RepRap, a host of commercial manufacturers are offering machines that can help people print parts at home. These include manufacturers such as MakerBot and uPrint Plus.

“Some of them are still very expensive and can cost anything from Rs 80,000 to Rs 7 lakh,” he says. “But the trend is going to change the way we buy things. You can practically make anything you break, lose or need. You can even edit and customize the designs,” he says.
“I’ve already replaced the broken leg of a Ganpati pedestal with a new plastic one I built myself,” he adds, rather proudly.
“I was approached by a Bollywood set designer who wanted to use the machine to create big objects, but had to explain that it is currently only for making small objects and prototypes,” he says with a smile.
Chaphekar downloads the 3D designs for his printer from a web site called Thingiverse (www.thingiverse.com) – a database of knickknacks made from 3D printers where hobbyists and artists share photos and videos of their designs.
The most popular models on the forum include retractable vampire fangs, a print-and-wear tie, a tissue-paper holder, Harry Potter glass frames and even chessmen.
“You can even design working prototypes of useful objects such as earphone holders, cloth clips, tape dispensers and pencil sharpeners,” he says.
As for his Future plans “I think I’ll use the 3D printer to print a new robotic arm and CNC machine,” he says with a laugh.

It’s my passion
Now in his third year of electronics engineering at Datta Meghe College at Airoli in Navi Mumbai, Chaphekar is constantly looking for things to make during his free time. “I am a DIY guy. It is my passion,” he says.
In 2010, he built a robotic arm along with his friend Amiraj Dhawan. The arm—made up of a base, shoulder, elbow, wrist and gripper—is controlled by a microcontroller and can be programmed to automatically reach out and pick objects. After that, he built a programmable engraving and cutting device called the CNC (Computer Numerical Control) machine that consists of a spindle and a bed.
The contraption uses computer input to automatically engrave various designs on wooden sheets. “The machine can work in all three axis to carve complex shapes – and like the RepRap, can be used to create prototypes,” Chaphekar says, holding the model of a wooden dinosaur he created using the programmable cutter.

The story was written for The Times of India and appeared in its Sunday edition.