Review of Brodak Electric Super Clown ARF with Brodak Power system
Hits: Includes almost everything (except prop and battery charger) to get you into electric control line flying at a price point of ~$300 list.
Misses:
1) Instruction book is not up to date with actual production kit. This had an impact (for me at least on the motor mount). Also missing key information on Power System (particularly the ESC and timer).
2) Nose ring is very weak. This is important since this is what is holding the motor to the plane!
3) Slight sanding needed on wing spars in able to slide battery into the wing slot.
The Brodak Electric Super Clown ARF is very similar to the "normal" Super Clown ARF except for a slot in the wing to allow the 4000 maH battery to slide in and the front end where the electric Outrunner Motor is mounted. I haven't checked whether the internal wing construction is strengthened, mainly because my "normal" Super Clown ARF is buried in a closet! I don't know the reason for the missing covering just behind the battery slot. I just guess that originally the battery was suppose to slide all the way back, but that CG considerations required it to protrude slightly from the slot.As it is, the back end of the battery is butting up near the from of that covering gap (see photo #1)
The plane itself builds pretty easy. Mine was all red with a blue rudder. Like most ARFS, you need to remove the covering where the wing, stab, and rudder are glued. On mine, the wing cutout was a bit oversized, so I stuffed thin balsa into the gap, made sure everything was squared and aligned, then hit the joint with thin CA. This does a good job of locking the wing in. Then I pour warm thin epoxy on the wing fuse joint. This grabs and seals the covering and fills any leftover gap in the wing fuse joint. One other thing I do is to run a black Magic Marker felt pen along the wing-fuse joint before pouring the epoxy. What is nice is after the epoxy cures on top of the black, it actually looks pretty good. I only say this because to me the joint between the film covered surfaces always looks kind of crummy and hard to hide. The epoxied covered black color actually emphasizes the joint.
The kit comes with pinned hinges for the ailerons, but CA hinges for the elevator/stab. I am not sure why. I replaced the stiff and "clicky" stock hinges with much smoother Du Bro hinges. However I went with the CA hinges in the elevator/stab because that wood is pretty thin. However I disagree with the way the instructions say to install the CA Hinges. I was taught to put the hinges in both stab and elevator BEFORE putting on the thin CA. This way the CA wicks in both slots. The instructions say to CA the hinges on the elevator first, then attach to the stab and CA again. I thought that if you do it this way, the first CA application may prevent the second application from wicking into the stab. I did it my way, but I can't say the manual's way won't work.
The most serious issue in my opinion was the nose ring. I attached the motor to the nose ring with the supplied two 3 mm bolts (actually you need 3, but I note the instruction book had a motor that only required two bolts). During a motor run up, I noticed a vibration--odd since one of the advantages of electric is the lack of vibration. The same thing happened when I switched the power off. Upon examination I saw the nose ring was separating from the nose. I easily pulled it completely off. One thing that bothered me was that the front end only had an 1/8 " edge to make the butt glue joint. I tried to epoxy the nose ring back on, but on another run up, the nose ring began to separate again (frantically reaching for the off switch!). Finally I decided to try another fix. I cut roughly 1/4" of the nose off. This exposed more wood surface to glue to (the nose has been sanded to give a nice sloping shape, so backing off gives a beefier edge to glue to. I cut out a new nose ring of 5 layered aircraft plywood and fit it to the nose. In addition I cut another nose ring. This one I placed against the nose, but scribed an internal line so that it would fit just inside the engine compartment. I then epoxied the two pieces together, and after it cured, I epoxied the entire assembly to the nose. The extra nose ring gives the whole thing a nice solid feel. I include a photo (#2) of what I did. I did contact John Brodak by e-mail and detail the nose ring issues.
This brings up the issue of the instruction manual. A very nice cowl (shown on the table in photo # 1) is supplied in the kit, but it isn't mentioned anywhere in the manual. I assumed that it was a cosmetic addition. It seems now that it actually is a structural necessity. I just read Mike Palko's review of this same kit in Control Line World magazine--unfortunately this arrived last week and all my excitement was two weeks ago! With my fix the cowl won't fit anymore. I could make a new one using the prescription given by Bob Zambelli in the same issue, but I think my fix is solid enough---besides, I don't have any condoms and don't think the wife would buy the argument that I need them for this hobby! (You gotta read Bob's method!)
Again a very weak part of this whole system is that nothing is really said about the power system and controller in the manual. The motor box does give some of its key parameters (kv=1500, 30 Amps max, 7 winds, input voltage range up to 14 volts). A small sheet that comes with the timer/switch tells you how to set the length of the flight and how to start the motor, but there isn't any information on the actual Electronic Speed Control (ESC). Hope he's right!! For example, I have a Sig E-Force, a small electric RC version of the P-Force. This came with a brushless outrunner, but I had to supply the ESC and battery. I bought a Castle Creation 10 Amp controller. From its manual I learned that if the prop runs backward, simply switch any two of the three motor<->ESC wires. The Brodak ESC needs a instruction manual like this. All I know about the ESC is what Mike Palko writes in his CLW review.
I did replace the battery and ESC connectors. The ones supplied are Tamiya type--the ones you see on the 6 cell NiCAD Packs that are pretty common on electric RC Cars. I changed them to Dean's Ultra connectors mainly because my charger was already setup for Deans (or Astro). During the soldering of the Deans onto the battery, I felt a little nervous, sort of like disarming a live grenade! Those batteries carry some stored power. The one that comes here is a 4000 mAH 20C LiPo. 20C means you can discharge it continously up to 80A. Of course 80 amps would only give you 3 minutes of running time (actually less, you don't want to discharge a LiPo to zero capacity). OOPs (2/3/07), I just realized that the battery is actually a 15C, not 20 C, so should only discharge at 60Amps for 4 minutes!
I haven't actually flown the system yet--need the snow off the ground. I am a little worried that there seems to be a lot of outboard weight, time and flying will tell.
One thing which really has attracted me to electrics is the possibility to really measure what is going on in a control line flight. The electric motor is a pretty simple predictable device when compared to your standard glow engine. To this purpose I bought an EagleTree Data recorder. This $70 device plugs in between the battery and the ESC. I also purchased a brushless rpm probe. So now I can measure both battery voltage and current plus the motor rpm while flying. The information is downloaded to a Windows (only sore point!) PC after the flying session. You can then see how the power levers were running during the flight. I include a plot of I took with three props on the Super Clown. The first was an old Top Flite 9-4, the second a Graupner 9-4 CAM prop, and the third an electric APC 9-4.5. Notice that the Top Flite was pulling over 40 Amps at the start. These values are all static, so the amperage should drop one the plane gets in the air--how much I am curious about. Notice the electric characteristic that as the load goes down and rpm goes up, amperage drops--good for the battery. These props can be seen, along with the data recorder (on the table) in the first photo.
Summarizing, I am looking forward to getting this puppy up in the air. The weight of everything except the 4000 mAH battery is 22.3 oz. The battery weighs 11 oz. So total up weight is 33.3 oz. I am curious what my (unbuilt) SuperClown ARF with a Brodak 25 + fuel tank weighs. Maybe I will build it just to find out how it flies and behaves in comparison the the electric.
Topic: Brodak Electric Super Clown and Brodak Power System review (Read 3176 times)