Team Pilots have been running the Flaco for a while now so they've had plenty of time to give me feedback. JFK flies the top mount and builds it as low as 16mm. He wanted more motor protection on the arms. Falcon wanted stronger arms. Control, on the other hand, rarely breaks arms. He switched to the top mount version and found that it mimicked the simulator best (he thinks simulators don't model low battery washout on turns). Sebring guest pilot Nurk likes the top mount version because he likes the fpv cam in line with the props, but he flew with the battery on the bottom. Finally, other Sebring guest pilot Danny Chan wanted a 5.5" frame that would be 5s or 6s ready. Me, I wanted something as simple as possible with a roomier stack.
I really like the Flaco's arm configuration – it's really cool that you can have a rock solid frame with just four screws (the FC screws also go through the arms, but aren't necessary for making the frame rigid). Since we're making a bigger frame, I thought it'd be cool to use the same configuration but bypass the FC screws to simplify arm changes. I drew it up, and...
Moving the arms to bypass the FC screws made the body huge, and while the whole point of this was to make a bigger Flaco, no one likes a frame THIS chunky. Back to the drawing board.
I abandoned the Flaco arm concept for a simpler two bolt design. It's a little less elegant but the upside is now I won't need two different arm styles. I went with a much slimmer center section, and a top plate that could accommodate a normal or a toilet tank battery. The cam pod is pretty similar to the low mount Flaco pod, and a major PITA to draw up. With all the lessons from Top Mount Flaco, the rest was pretty easy to whip up.
As in the Top Mount Flaco, the pods are only 15mm tall, leaving a 5mm gap in case you need to run wires under them. That also gives you the option to really slam your build with 15mm standoffs, in case you're a magician like JFK. The arms are 6mm thick and taper from 12 to 8mm, so they should be substantially stronger than Flaco arms while incurring minimal thrust loss. Other than that it's pretty simple, just three distinct carbon designs and two printed parts that you can print yourself.
JFK really wanted some motor protection, so I drew up some really chunky armguard/motor soft mounts. It all seemed pretty reasonable 'til I printed it out and put it on an arm.
This was waaaay too big and heavy, but I guess I can put it up on Thingiverse if someone wants a ridiculous amount of motor protection at the expense of weight in the worst possible place, as far from the CG as possible. The next revision was far more reasonable.
The frame's a beastly 122g with armguards, which is about right for a bigger quad that's going to have to hold up to the abuse of higher voltages and more mass and inertia in crashes.
I built mine up with an aio fc + esc, which made it really easy to fit everything inside (but it doesn't have filtered power for the vtx or smart audio, so I wouldn't recommend it). I had some XNova 2204 2300's so I threw those on. Control flew it back to back with his Top Mount Flaco, and he was able to transition almost seamlessly between them. The main difference was that mine lacked a bit of low end torque on sharp hairpins, which was to be expected since he was running Ummagawd 2306 2150's on 5", while I was on 2204 2300's on 5.5".
JFK and Falconx liked theirs as well, the most surprising feedback coming from Zach, who found it the most controllable frame on the tight Vegas course.
You'd think a small frame would be easier on that course, but maybe the extra mass makes it more stable?
Next I drew up a Session mount. CG is perfect with just a battery up top, now with a Session above and the battery below the CG's a little below the prop line. Not perfect but pretty close.
I'd just started sponsoring John Shrout of Area 51 Films, who specializes in shooting action sports. He's flying the Hero on an Ichabod and the Session on a Flaco. He took a look at this and asked if 6" props would fit, and whaddaya know, they just fit. I took it out and flew it on 5.5 and 6, and was disappointed to see that there was a good deal of jello in the footage. I guess my props were pretty dinged up. So I drew this up:
I just picked up a Hero6, and this frame, which started out as a 5.5" racer, was starting to look like it could be a good 6" chaser, a faster but less flexible alternative to the Ichabod – you can't have props out of view at lower cam angles. I flew it on 6" and the footage was amazing. Baseball players were moving in on us so I didn't have much space to work with, but you get the idea. This camera's just incredible.
Those mounts are 45 degrees. Now, if you set up your Solidworks files properly (by anchoring every move on a preceding move) you should be able to change one thing and have the part re-draw itself perfectly. I came within one move of getting the Hero mount to redraw itself at 35 degrees. So close.
35 degrees just barely keeps the props out of view, but then I found something interesting while reviewing the footage.
If you watch the lower right corner you'll see the prop nut intermittently creep into view. That's the Hero's stabilization at work. I made a 37 degree mount and that's the minimum angle with no props in view.
Meanwhile, here's a quick flight by Control on my rig so you can see it at proper speed. You can see he's not totally used to it, but it's close enough to his Top Mount Flaco that he can zip around pretty quickly. It's interesting that 5.5" props feel a lot more like 5" than 6".
Meanwhile, more Gordos went into the wild to rave reviews, so it's ready to go. The cam pod has two versions, for 2.1 and 2.3 lenses. The rear pod can take an SMA, or a UFL Axii. I recommend the SMA tail for racers for quick LH/RH antenna swaps. You can mount your battery normally or toilet tank style, but mounting it normally is a better option since it puts the standoffs under the battery and takes stress off the top plate on impacts. Top mount configurations are notorious for getting battery leads chopped, but if you set things up just right it's not a problem at all. A balance lead saver helps too.