Rachel and I have returned from our European honeymoon and the crew and I have been hard at work on bringing the OpenBeam Kossel Pro to production. I'm happy to announce that we've hit three major milestones this week;
1) The tooling for our extruded aluminum vertex profile is done! We are happy to locate an American manufacturer to manufacture this part. I had an opportunity to tour the extrusion plant a few months ago and it was very reassuring to see that they do extrusion, cutting and anodizing all under one roof. As many of you may know, we fired our primary aluminum extruder early this year due to consistent quality concerns. Even at the very end, we still couldn't establish WHY the parts are bad with the extruder pointing fingers at the anodizer and me scratching my head wondering how the anodizer can produce straight bars the first time but consistently bend my extrusions 4-5mm / meter on the new orders.
We are currently awaiting samples to be shipped to us. These parts are coming in cut to length and anodized (black), but not machined. The features such as screw holes, motor mount face and access ports for screw drivers have to be machined in. We will be working with local small business machinists to perform the final machining steps to finish the part.
2) We have finished our Proto-B design review process and incorporated all the feedback from testers into our parts to prepare the files for injection molding. The injection molding process is by far the longest lead time item in this project; it clocks in at 7 weeks after mold design is complete. It had been a major source of embarrassment to me to have to launch this almost 3 months behind schedule, but we only have one chance to get this right. Launching tooling will be the subject of another blog post - it is a lot more than just sending our STP files to a vendor. We've also been test building, modifying and rebuilding the end effector and auto level / bed probe assembly; both of these went through about 2-3 major design revisions before we are comfortable and happy with what we have. (Yes, those are thermal camera images; we borrowed a FLIR thermal imaging camera to study the cooling for the hot end as well as to see how efficient our thermal cooling for our Brainwave II board is. You can see just how sensitive the camera is - it picked up the thermal footprints left by the dog after she walked across the carpet. With this baby we hope to be able to tune the cooling profiles of the micro-processor controlled fans in the end effector).
3) We have been developing the Brainwave II in the background for the past 5 months; and tonight I'm happy to let you know that the Brainwave II had completed systems integration testing. There were obviously some rework done to the board (as seen in the pictures) but we have verified all core functionality and successfully completed the Arduino Hardware bundle for the board (which greatly simplifies programming the board) and made the necessary modifications to Marlin to make the firmware work with the new board.
We haven't been updating the project as frequently as we'd like; the focus on the past 6+ months had been to "keep head down and jam out the design" Now that we are on our way to launching all the long lead time tooling, we have more time to allocate towards blogging and social media outreach. (We also have been growing the prototype fleet to get more combined test time and tuning time in). We look forward to finally sharing our design process and trade-offs with the world!
-=- Terence, Mike, Matthew, Johann, and the crew of Metrix Create Space