Up earlyish (though later than weekday normal), and off to the Electronics Flea Market. 'Twas rather disappointing, compared to years past; there was some cool vintage stuff, and some oldish test equipment that would have been good for equipping a new lab on a shoestring budget, had I not a full set of basic equipment already, but... just not a lot of people, nor a lot of really cool stuff. Met with someone I'd encountered at Maker Faire, and had a lengthy discussion of nifty ideas, some of which may come to fruition in the fullness of time.
Then off to AeroMicro for a couple of odds & ends. (Really, it would have been less trouble just to buy my first electric RC plane there: local, with staff who are Into The Hobby and know their stuff, and it wouldn't have been that much more expensive than buying on-line.)
Then! Put in an appearance at the TechShop open house. People showing off their Cool Stuff (some of it very cool indeed). Rather a smaller event than I'd expected... but there'd been on in SJ last week, and SF the week before that, so perhaps everyone was TechShoppEd out.
One the way home, swing by TAP Plastics for some Stuff for a project I'll maybe describe later.
Then home, and I figger I might as well unBix the boxler unbox the Bixler and have a little closer look.
The assembly instructions aren't nearly worthy of the name. If you're putting together the "Almost Ready to Fly" version, you'd better have pretty good mechanical aptitude and a fair idea of how things are supposed to go.
Fuselage disassemblement to allow motor installation took a bit of figgerin'. I had to cut through the gummy glue holding the top fairing over the motor compartment in place.
Having more or less figured out how things go together, I proceeded to install the 3.5mm bullet connectors on the speed controller, clamp the motor mount in a vise, connect ESC to radio and to a bench power supply set for mostly-charged 3S LiPo, and verified that (1) the radio-ESC-motor path works; and (2) matching colors of the motor leads turns the prop the right way.
Oh, radio. Servo connectors. Orientation of connectors is not clearly marked, and the manual (once found and downloaded) is no help. What to do? I had a couple of old-ish Futaba micro servos sitting on the bench; they have physically keyed connectors. Do they plug one way and not the other? Yes!
...Wait. Is that actually right? I should be able to check this with a continuity beeper: the ground and power rows should connect straight across, while the signal row should have all separate pins.
Uh-huh.
The way the Futaba servos can be plugged into the HobbyKing radio is exactly and perfectly backward.
I assume the servos that came with the plane are not physically polarized, so the problem there will be merely one of ambiguity and not positive wrongness. Still, 'twould be nice if these things were standardized.
And, while I'm at it: yes, the cavity within the fuselage of a Bixler is juuuust wide enough to accommodate a Raspberry Pi. Removing the composite-video connector might be helpful.
Anyway: I'll probably get the Bixler actually put together in the coming week, and maybe even find an opportunity to put it in the air, using the store-boughten radio. (And maybe there are parts of the assembly I want to do with gummy glue rather than really permanent stuff...?)
Nearer-term tinkering time, such as it is, should really go to checking out the bits of the planned flight-control system. Maybe tomorrow afternoon....
Update: found actual Bixler (and similar) assembly instructions here. Step 1: "Dispose of the instruction manual (4)." This seems to be for a slightly different version, but should prove useful. 'Twould be even better if the manufacturer, having the CAD files and all, had generated some nice diagrams showing what goes where and how it's meant to be affixed, but user-group docs are still helpful.
(And I have the feeling I'll be annoyed by the lack of tie-downs, bulkheads, and suchlike. I have this quaint notion that everything aboard a flyin' machine should be firmly anchored to avoid shifting around and affecting balance... and things like inertial and magnetic instruments, in particular, should have a permanent fixed relation to the airframe. Oh, well: glue. And - d'oh! - velcro (not included (update: hey, the small-parts bag has some velcro bits in it)), for the parts that need to be tethered but not with precise orientation.)
Further afterthought: I reversibly affixed the canopy to the cockpit insert with common pins from the Tackle-Box of Sewing Stuff. This could set a precedent for locating inner items such as nav platforms; perhaps I'll throw together a location jig (could be made of heavy paper) for getting holes in well-defined locations on the sides of the fuselage, and use pins (or some approximation) for holding stuff in.
Heavy stuff probably wants better mounting than that, though, lest a rough landing cause the pins to slice through the foam.
I probably want to mount the Pitot tube before gluing the halves of the fuselage together, just to keep things easy. Hmm, and make some allowance for placing the magnetometer / air-temperature probe, which would also be much more difficult after assembly.
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