I was recently notified that a neighbor kid back home had given me his old Firebird Commander 2. This is the second beginner plane to be handed off to me by a neighbor
Anywho, my primary concern at first was that I'd need to find a way to cut it into tiny pieces and dispose of it without him finding out. The plane is like a textbook example of electric models from decades past - Ni-MH pack, brushed 400 motor, two channel radio, fishing line and rubber bands for bang-bang ruddervator actuation with a single board-mounted "servo", plastic pod fuselage, and that horrible coated-meat-tray foam for the wing. I would be less than enthusiastic to receive one brand new... Nevermind the fact that this one's hit the dirt a "few" times. I gave it a repair-shop job last summer in the hopes of getting the kid flying on it and I recall thinking that it wasn't in great shape. I DID get it airworthy then, so all I can hope for at this point is that it hasn't gotten worse than it was.
WWEEEEEEEELLLLLLLLLL.... My brain was running at an idle today and my thoughts turned to this plane. What's stopping me, I figured, from gutting it completely, cleaning it up, and modernizing it? I have plenty of equipment options in my electronics box back home for a 40" pod-n-boom parkflyer. I have to admit that there's something about the design that I really don't mind. It sort of rides the border between cute and sexy.
Posted by C₄H₁₀ |
Mar 15, 2013 @ 07:36 AM | 3,839 Views
Been wearing my thinking cap lately. I keep running into the same question over and over: "Why isn't there a Speed 400-class sport racer designed for modern power systems?". It's no secret that a $10 outrunner can give a $100 Mega a serious run for its money in a race (efficiency be damned), but the NanoPlanes BSS and maybe a modded Slipso are the only airframes out there in this class that will comfortably take one of these motors. I decided that this needs to change.
The 26" balsa/glass Scorpio 400 has been designed from the ground up to take full advantage of more modern, widely-available power systems. It's sort of like the love child of a Slipso and a Turbo flea, a small balsa bullet specifically designed to use cheap, fast outrunners and high-discharge lipo packs. The forward-swept wing is theoretically supposed to help with stall and turn characteristics... But more importantly, it looks cool I originally figured it would come out looking more like a scorpion (hence the name), but it has a distinct bird-like quality to it. All the good bird names have been used a thousand times, so I think I'll stick with Scorpio.
A lot of details will probably change between now and whenever I get a chance to build a prototype, but I do like what I've got so far. These renderings are a little rough since I was just trying to put polygons on paper, but I'll hopefully get it looking nicer soon. If anyone wants to go ahead and be the first to build one, I can give you a more complete set of measurements and details and such.
Posted by C₄H₁₀ |
Jan 10, 2013 @ 11:10 PM | 3,828 Views
I bought the Axe (first version) many years ago before I moved out of helis and into planes. It had eCCPM control, a brushed 400 motor, a 9-cell Ni-MH pack, and one of those godawful 3-in-1 control boards. I don't recall exactly why I stopped flying it. I believe it was related to isues with the tail motor that just wouldn't go away, and then eventually I think the radio just plumb stopped working. Well, THAT was quite awhile ago.
I have a HobbyKing gyro that I bought for no good reason, and I can probably scrounge up three servos... I have all the other stuff I'd need for a full-house brushless main + tail setup, too. In short, there's virtually no reason I shouldn't be able to put it back in the air very quickly.
So I just wrestled the stock motor out and installed an Electrifly Ammo 2040-size, 3500Kv inrunner with a pinion I found in my motor box. Hooked up an ESC and a servo tester, still not totally committed to this spur-of-the-moment idea... And then I spun up the blades and realized that the sound alone is probably half the original addiction.
I surely need a linkage set and maybe a feathering shaft, and then just a bit of elbow grease to get this old bird flying. I checked Tower and, being the good ole Hobbico stagnation pond they are, they have a full line of replacement parts in stock. Cool. Only problem is that I'm heading back to Fairbanks in four days, so I have virtually zero time to monkey around with shipping. I'm gonna check the hobby shops tomorrow to see if any Axe CP linkage sets got kicked under a shelf some years back, but I suspect I'll have to place an order with Tower anyway. Hmmph.
But for now, it's looking like a quick whirlwind of hunting down and mounting the requisite electronics, and then figuring out a half-decent way to stick a lipo in where a Ni-Brick used to sit. Let's roll
Posted by C₄H₁₀ |
Sep 23, 2012 @ 03:18 AM | 4,589 Views
I get more inquiries about this plane than any other I've ever built. I decided that I'd do this quick write-up with some pics so that I have somewhere to refer all you guys who want to know more about it.
This was my first built-up balsa plane, built somewhere around April 2011. I had a rough idea of what I wanted to build, but I never drew up any plans or anything. Just started cutting balsa and making it up as I went. It was originally intended to be a sort of park racer or fast aerobat in the 75mph range and was designed around the venerable Suppo 2212/6 motor and a 5x5 prop. It has full 4-channel control and was built with dual aileron servos for setup simplicity and control options (flaperons, differential etc.).
The open tail structure seems to be a point of continued fascination with this plane. That was actually the second fuselage I built for it; the first was more similar to a Slipso in construction and couldn't accommodate the motor it ended up with without tearing off the firewall on landing. The first-version closed fuselage was destroyed not long after I built it, so I replaced it with the open-tail one which had significantly more interior space and allowed me to mount the larger Suppo 2217/6 internally which I found to be more appropriate for the plane. V1.1 flew great (incredibly well, actually) but had a few spots that sat rough with me. They were mostly just basic design/construction things, but they made it less-than-perfect.
Posted by C₄H₁₀ |
Aug 21, 2012 @ 10:44 PM | 5,292 Views
This is pretty much just a compilation of some of the various pylon-type planes I've built over the past few years. Pics and basic specs of each just for fun.
- Slipso400 -
I started this one about a week ago, two days before I destroyed the blue and white one. Notable changes include a longer, higher-aspect-ratio wing (32" span, 4.25" root chord) that's made from a 3/8" plank, and a slightly wider, deeper, and longer fuselage. All parts blend smoothly together for a virtually seamless, incredibly slippery profile. Should be finished soon, hopefully.
- Slipso400 -
This is the newest Slipso I've built. Fully glassed, Venom V40 motor, 3S 1800mAh pack, 30A Jeti ESC. I think I finally did the linkages a way I like them, and overall I'm happy with the looks and such. Haven't maidened her yet but I'm expecting ~130-135mph.
**** EDIT 12-13-2012 ****
This Slipso was maidened a few months ago and flew very nicely. I've now got a Mega 16/15/2, 4.1x4.1, and a 60A ESC to drop in. I'm expecting 150mph as a conservative number with that setup, but it'll depend on how well my packs are holding up.
**** EDIT 1-4-2013 ****
A few days ago, after (I think) three excellent flights with the Mega setup, I wrecked this one by inadvertently activating the Delta Wing mix on my transmitter while navigating to its model memory slot. Went through a couple trees and then the ground. Its replacement has been on the bench for some time now...
Posted by C₄H₁₀ |
May 28, 2012 @ 12:09 AM | 5,394 Views
This weekend I acquired a burned-out Grayson MicroJet V3 motor. It's a little 39g, 28mm outrunner that's identical to the Suppo/BP 2208 line of motors, but rather than orange anodizing it's just silver all over.
I've been wanting to rewind one of these little beasties for awhile. I've got four of the Suppo 2208 motors in various stock winds, but they all run perfectly and there's no sense in tearing up perfectly good motors. The MJV3 came as a lovely, if damaged, addition to the herd.
The motor has twelve stator poles, fourteen magnets, and was wound with eight delta-terminated turns of what appeared to be a five-strand bundle of 30AWG wire. It is claimed to have a Kv value of 2200 in its stock form.
Taking apart and unwinding the motor was an uneventful process. No major trouble was anywhere to be found and the stator remained green and solidly coated. My initial plan was to rewind it back to factory specs, but a conflict of available wire gauges made this difficult.
I eventually settled on a double-strand, eight-turn wind with something like 28AWG wire. My wire is all salvaged from transformers so I don't know exact sizes, but it's right around there. I did a classic dLRK wind terminated delta and soldered up some connectors. She tested well but got very hot for my tastes. I suspect I missed a few turns here or there. The motor was obviously very aggressive in the Kv department as well; this thing was seriously cranking and drawing about 2.00-2.10A with no load.