RepRapMicron Is an Attempt to Bring True Precision to 3D Printing

3D printers are incredibly useful tools that can churn out functional prototype parts in mere hours. But 3D printing isn’t known for its precision or accuracy. Those are independent — but related — characteristics. Most 3D printing processes can’t realistically achieve consistent tolerances better than +/- 0.1mm (about 100μm), which is very loose when compared to even conventional precision machining. But what could hobbyists achieve with a 3D printer capable of micrometer tolerances? Vik Olliver wants to find out and is in the process of developing the RepRapMicron.

The history of the RepRap project is fascinating and all consumer 3D printers on the market today owe at least some credit to it. But it has stagnated in recent years, as big leaps in innovation have become less common. RepRapMicron is the first project we’ve seen in a long time that has the potential to be truly revolutionary.

At its heart, the RepRapMicron concept is just a normal 3D printer scaled down to work on tiny parts. But when the features of those parts are measured in micrometers, most conventional 3D printer designs go out the window. The two biggest challenges are accurate positioning and predictable extrusion.

Almost any 3D printer today can achieve the precision necessary with some gearing. But accuracy is a different story. Even imperceptible slop in a gearbox would ruin the accuracy. To solve that problem, Olliver turned to the OpenFlexure project. It produces designs for 3-axis mechanical positioning systems built using loose-tolerance 3D-printed parts. Its original purpose was for high-performance hobbyist microscopy, but it is the perfect solution for positioning on the RepRapMicron.

The bigger challenge will be extrusion. For reference, a strand of spider’s silk is 3-8μm wide. The goal for RepRapMicron is to print at 1μm. Traditional extrusion and materials simply do not work at that scale. Olliver plans to utilize some form of deposition, possibly with existing photosensitive resin—though it would need to be much lower in viscosity than what retailers usually offer.

This will take a lot of experimentation and development before it gets anywhere, but the potential is enormous. This would open up a whole new world of DIY MEMS (micro-electromechanical system) fabrication to hobbyists. Such capability will enable the construction of truly high-tech devices, which are far out of reach right now.

So far, Olliver has built an OpenFlexure test rig. That will let him start experimenting and we can’t wait to see where the RepRapMicron project goes.