High Resolution shots of the printer's output here:
About a year ago, I designed the OpenBeam Construction System as a low cost way to rapidly build mechanical prototypes. One of the application I had in mind was the construction of 3D Printers. Up until OpenBeam, the traditional method of building 3D Printers was with 3D Printers.
3D Printers are great, and we have been involved in the 3D Printing community for a very long time. However, when used in a production setting, it quickly becomes an artificially created bottle neck in work flow and a possible support issue as well due to variances between parts. So, with the OpenBeam Construction System, we chose to do things differently. We designed components that form the fundamental building blocks of 3D Printers and other small scale automation machines. These components are designed to be as modular and reusable as possible. This way, individual components can benefit from the economies of scale of modern mass production techniques while still allowing designs to iterate and evolve.
Design Philosophy of the OpenBeam Kossel Pro
After Johann developed the ground breaking work behind the Rostock 3D printer, I donated some material to him to work on the next generation deltabot, code named: "Kossel". The team at Metrix Create:Space have been working on and off on the Kossel and it's bigger variant Kossel Pro for the past six months, and we are now confident enough in its design to be launching this Kickstarter.
We will be designing our parts for maximum interchangeability between the Kossel and the Kossel Pro. We expect that parts such as the extruder body, the end effector, the ball joints, and the carriages to be reusable between the two machines. We will also be intentionally over designing our parts - for example, we are using a commercial linear ball recirculating rail, and we will be designing a fully ball bearing arm joints. Such features may not be necessary for a machine the scale of the Kossel / Kossel Pro, but by over designing, it allows for future expansion - larger printers, more aggressive printing speeds, multiple extruders, etc. These features are beyond the scope of this current kickstarter, but we hope that our contribution will allow others to build off our work.
Build Area: Cylindrical Build Area of 250mm Diameter x 250mm Height
Linear Actuator resolution: 0.2mm / full step, 1/32 Micro stepping
Extruder: OpenBeam designed Dual Use extruder body. Includes parts for both standard NEMA17 stepper mount and geared pancake motor. Extruder can be configured for both direct drive and bowden drive.
Hot End: Testing so far had been done with genuine J-Heads from Brian Refsnyder; if stretch goal is reached, we will be testing our own full stainless steel hot end design.
Swing arms: Carbon Fiber swing arms with OpenBeam designed full ball bearing ball joints.
Linear Bearings: 12mm Recirculating ball linear slides.
Electronics: Metrix Brainwave
Heated Bed: Optional.
Specifications are only part of the story. If you will be at the Bay Area Maker Faire, come by to the Metrix Open Hardware Alliance Booth to see the printer in action and say hello to some of its designers!
OpenBeam is committed to being a good member of the Open Source Hardware community. We donate a percentage of our proceeds towards open source hardware causes; we are a member of the Open Source Hardware Association, we sponsor the development of Slic3r and other slicer programs with monetary and hardware donation, and we are sponsoring our local mini Maker Faire in Seattle. For this project, we will be working closely with the folks at Metrix to grow the Metrix Open Hardware Lab. We are going to do something really cool that will change the way people fundamentally think about prototyping electronics. We can't tell you all the details yet, except that it will be something really, REALLY awesome.
Acknowledgement and Special Thanks:
The OpenBeam Kossel Pro is 100% Open Hardware. We wouldn't be able to achieve what we've done without building on the works of those who had come before us. Specifically, we would like to extend our thanks to:
* The RepRap project.
* Johann Rocholl, for his pioneering work showing the world that delta-geometry robots are possible for 3D printer work
* Matthew Wilson, for his work on the Brainwave board, and challenging conventional wisdom of what's required for 3D Printer control electronics.
* The development team behind Marlin and Repetier Host* The guys on the Deltabot Developer List.
* Matt Westervelt, Marc Goodner, Matthew Wilson, and Richard DeLeon - the Alpha Prototype build crew. Their feedback had been invaluable in shaping the development of this printer.
Additionally, I would like to thank the following folks:
* Martina and Karm Ning Tam (my parents). My father especially, who has been helping me with the supply chain issues.
* Rachel Flamm, aka, future Mrs. OpenBeam, for not throwing me out of the house when I haul home a piece of antique electronics or a boxes of aluminum bits and leaving them around the house.
* The staff at Metrix:Create Space, for running one of the most awesome hackerspaces on the planet, for fostering the Seattle 3D Printer community, and for all the prototyping work that they've done on the Kossel Pros.
And lastly, we like to thank our supporters, for your continued support for Open Source Hardware. Thanks for reading,
-=- The team at Metrix, Terence, Rachel, and the furry monster puppy
Risks and challenges
First of all - a disclaimer. We endeavor to make the Kossel Pro an easy to build 3D Printer, but please understand that 3D printers are not household appliances like a microwave or TV. Both the building and operating of a 3D printer requires careful attention to details and a certain level of mechanical skills. This is true with ANY 3D printer that is currently on the market. The Deltabot design represents cutting edge, state of the art in Open Source 3D Printers - and being on the bleeding edge comes with the normal trade offs that early adopters will face.
We've mitigated against a full blown, "sh!t the bed" sort of failure (ie, the thing not working) on this project by building and testing multiple Kossel Pro 3D printers over the last 6 months to validate the design concept. We did not simply run to Kickstarter when we got our prototype running - we built multiple machines with multiple members at Metrix, tested different configurations, and experimented with different assembly methods. We will be systematically replacing all the laser cut and rapid prototype parts with mass produced parts (either via injection molding or metal stamping) that will be more accurate and repeatable. The result should be a vastly improved design than what the alpha testers have been building, in terms of machine accuracy and stability.
The biggest risk is a schedule slip. We have learned from our mistakes on the OpenBeam Kickstarter (which delivered majority of the rewards early, despite being overfunded by 300+%) and will be applying what we have learned onto this Kickstarter project. Specifically we are doing two things: 1) We are hiring someone whose day job is to create assembly documentation to do the actual assembly documentation, and 2) we are limiting the number of kit configurations and the choices people can make on their machines to streamline our fulfillment.
When a 3D Printer kickstarter project like this launches, people inevitably asks for more and more upgrades - dual extrusion, printing with nylon, etc. While it is great to be so enthusiastic, the harsh reality is that good execution of a design project requires guarding against scope creep and focusing on the priorities and tasks on hand. As a result, we have already laid out all the stretch goals for this project, to prevent scope creep from taking over the schedule. The schedule that we've posted is one that we are confident to meet or exceed. At times these measures may seem heavy handed, but we would rather under promise and over deliver instead of promising the sky and then being a year late.Learn about accountability on Kickstarter
- (44 days)