The DeltaMaker: Robot Meets 3D Printer

The DeltaMaker, a recent success on Kickstarter, is an elegant 3D Printer built on a delta robot platform. Delta robots have been used for picking and packaging applications in factories for decades, thanks to their impressive speed and agility. The DeltaMaker uses MakerSlide aluminum extrusions paired with Delrin v-wheels on bearings to move quicker than normal printers; the Z-axis isn’t limited by the low speed of a threaded rod, for example.

I spoke with Zack Monniger, DeltaMaker’s Mechanical Engineer, about their printer and delta robots in general:
 
Hi Zack! Can you tell me about what you do for the DeltaMaker team?
I have two distinct roles. Role 1 is the Mechanical Engineer of the group. So I’m in charge of maintaining the “virtual” version of the DeltaMaker and all of the detailed part design and drafting that goes along with that. As a result, I’m also kind of in charge of the BOM (by default) and putting some basic engineering documentation control procedures in effect.

Role 2 is the “business guy”. That’s the boring stuff that I don’t think anyone is too interested in.
 
Besides being more fun to watch, what are the advantages of using a Delta orientation for 3D printing?
From the mechanical design standpoint, you get some cool features with a delta. Designing a 3D Printer requires that you make trade-offs between mechanism speed (and print speed), mechanism accuracy, and the build envelope.

Essentially, you’re fighting a battle against momentum. The less the moving parts weigh, the better off you are. The DeltaMaker tries to get the best of both worlds. It uses a high-end linear motion system (built around MakerSlide aluminum extrusions), and minimizes the moving mass. This means we can address a large volume with the print head, and do it quickly.

 
What are some challenges you face when building and designing a Delta machine, as opposed to a ‘normal’ cartesian machine?
In a lot of ways, the delta approach seems like a more natural fit. As discussed earlier, speed, accuracy, and build size are competing constraints with a 3D printer. When you watch videos of industrial delta’s in action, it’s pretty remarkable how fast and accurate the systems can be. So from a motion system standpoint, we feel like a rigidly built delta is a great platform for personal 3D Printing. If designed properly, its also very scalable (both smaller and larger).

From the software side, the Rostock project by Johan is a great enabler, as open-source firmware supports the “delta-space” conversion on the printer side. So with Marlin, Slic3r, and Repetier Host available as open-source software solutions, it lets new guys like us focus on making awesome hardware.
 
Are there any 3D Printed parts used in the printer?
We do not intend to ship production printers with any printed hardware – 3D Printing did its part, now we’re moving on to production hardware.
 
What are the speed and print size limitations of the DeltaMaker?
We’re optimizing for a 10″ diameter and 11″ build height. One of the great things about this design is the ability to scale in all directions. We’ve posted a video on YouTube (watch it below) with real-time motion up to 200 mm/s. We plan to push that further as we start swapping out printed parts with production hardware.

How much more complicated is it to setup and calibrate a delta bot?
Overall, the challenges are comparable to other systems. Auto-calibration is our plan and something we are currently working on. Unlike a cartesian machine, X,Y,Z are abstracted from your actual motion system. So while either system can be calibrated mechanically or in software, a delta mechanism seems like a more natural fit for a software calibration, so that’s something we are really focused on.
 
What excites you most about the future of 3D Printing?
I used 3D printing technology frequently as a design engineer working in industry over the last 10 years, but we mostly called it “rapid prototyping”. We had a lab with 2 or 3 guys and 3 or 4 big industrial machines supporting a large engineering workforce. The technology has been around for decades, advancing in the industrial space and being a great enabling technology for well capitalized businesses.

What excites me is the democratization of product development. The DeltaMaker, as a product, was enabled by low-cost 3D Printing. With mechanisms like Kickstarter in place, and enabling technologies like 3D Printing, a small team can get a product in front of consumers for a fraction of the cost it would have taken just a few years ago. You don’t need huge sums of capital to get something out and test the market.