A most excellent workshop today. I’m not surprised we didn’t get close to finishing but I learned a lot about foam board and I’m very pleased with what I’ve done so far and with all the received parts.
I’m looking forward to continuing to build this superb (and huge!) plane.
Thanks again for this very useful workshop and for your time and knowledge… and pizza!
Yes, thank you! definitively need more time to finish the build (or pre-cut the foam board with a laser).
I’m going to finish the build of this airplane, but I can already tell I’m going to have to cut another one. my cuts are not very even or symmetric.
I played around with the electronics. That is one very powerful motor. Did we get the high power or the low power model?
The 5v supply from the ESC is fairly noisy, but probably good enough for this build. Definitively too noisy if you plan to add an inertial platform for auto-pilot.
I have an issue with my battery charger. After close to two hours charging the large battery pack (2200mAh), the charger indicated cells 2 and 3 were charged (green light), but cell 1 was still red. I left it charging for another hour, but it never changed to green. Fearing a faulty charger and a lipoly fire, I unplugged the battery and checked the voltages:
(black) cell A (white) cell B (yellow) cell C (red)
I had:
cell A: 4.20
cell B: 4.18
cell C: 4.26
uhoh … 4.26. I read plenty of bad stories about lipoly batteries being overcharged and their results. I checked the pack, and maybe I’m being paranoid now, but it does have a puffy look.
( from what I read, 4.22 is 100% charge, anything over is bad. With most advanced users recommending to not charge beyond 4.15 in order to maximize battery life and keep internal resistance to a minimum)
So, do I have a bad battery? a bad charger? a bad charger that has now damaged the battery?
Yes, it definitely would have been better to laser cut everything. At about 8 minutes per sheet though, it would have cost me about $300 in laser time at MakerLabs.
Next time hopefully the VHS laser cutter will be operational.
Next time we can meet up at the space I’ll swap your charger and battery for new ones, and I’ll put the suspect one on my iMax charger to discharge and recharge… In the mean time it’s probably best not to use it.
If anyone wants to get a whole new set of parts for the FT Explorer, you can buy a Speed Build Kit from Great Hobbies for CAD $52 (they have lots of other FT kits too, most of them are cheaper). They have free shipping for orders over $100, so if you’re tempted, see if someone else wants to go in with you.
You can also get just the fuselage direct from FT for USD $20 but I suspect the shipping will be expensive… Since it’s just two sheets of foamboard it’d actually be cheaper to laser it at MakerLabs.
I just discovered you better really secure down the motor if you want to bench test it…
A small pcb holding vise doesn’t really cut it…
Good thing we got 2 propellers…
Might need a new motor cuz this one got a bit banged up when it flew across the workbench and everything ended up in a tangled web of wires…
Uh, yes, I probably should have warned you guys about that.
The motors are powerful, the props are sharp, and you are made of mostly water!
Run the motor up to full throttle without a prop on it , if the ESC doesn’t release the magic smoke and the motor doesn’t vibrate too much it should still be fine. Otherwise I’ll sell you replacements at cost.
How are the foamies coming along? I spent last Sunday finishing off mine so it’s pretty much ready to fly. I covered it in foil tape to keep the water out just because I had a spare roll!
I Also ordered a trainer cable so we can link up the transmitters for teaching people how to fly if some ppl are new to the game.
Hi Hector! Sorry it’s taken so long. I’ve replaced the suspect battery and charger with ones from my stock, back in your envelope, in the dropbox. Let me know how it goes!
By the way, has anyone else tried out their chargers? I’m curious whether this is a one-off or a bad lot. I haven’t tried any of them either, FWIW.