Originally Posted by FenixPheonix
Team 751 does all our own manufacturing for one simple reason: we don't have the resources.
Let me explain. Our team has, in terms of manufacturing, a manual mill, lathe, drill press, four hand drills, a drop band saw, a vertical bad saw, a sander, a grinder, and a TIG welder that we got half-way through this season. We have a small team of fifteen students, and a highly devoted core of less than eight. As such, we have to balance both man-hours and machine hours. For every day-long mill job we set up, we sacrifice another, and lose design time for some area of the robot. And that is precisely why we, the students on the team, choose not to outsource our work. We've found that the lesson in practicality and trade-offs is more valuable than the functionality that we would gain from outsourcing. If a person on our team has a great idea that would need three days of manufacturing time, we all sit down, and run cost-benefits analysis on it. Is one day of mill-time and a student day worth half a pound of cheese-holing? We run into this one a lot. Most of the time, we say it isn't. But before SVR, we realized that, for one part, it was, because that half pound let us change out our corner wheels from Plaction for Performance, letting us solve the wheel breakage issues from Sacramento (cracked one in half and dented three to the point of being unusable crossing the bump.) So we spent the time, and ended up below the weight limit.
And it's precisely because of our in-house work that we CAD everything. We design all our parts, do time estimates, and schedule our machine time, going for maximum efficiency. We've got folders of part layouts that students just churn out, organized by sub-system and machine utilization. Our drivetrain was fabricated (not assembled, Andy-Mark shipping held us back) in three days, and everything else took us about nine. Everything was CAD'd, everything was prototyped. When you know how to run design well, you can streamline manufacturing. CAD is vital for optimizing machine schedules and ensuring that we can make everything, and producing accurate drawings our designs (very few of which are made by the person who designs them. That's usually for the few that we decide need the machining time the most for optimization, as we want the person who understands the design intent and manufacturing process, having designed both.)
We're looking into expanding our manufacturing abilities with another manual mill, and possibly a CNC. We are also hoping to get access to a local waterjet (at the TechShop. We've also done a bit of laser cuttig there.) This will eliminate some of the urgency of the scheduling (though I have no doubt that our designs will become more complicated to saturate our machines again.) However, we will continue to design and build all of our own parts, as we find it promotes a culture of responsibility and efficiency.
My point here is: we build in-house to teach our members about time and resource management, at the cost of some machine functionality. Is it worth it? Depends on what you want to get from it.
|