Axe CP separations and setup journal

[Phishnvdub]

Hi Ray, I got my prop at allerc.com. It's the GWS gray ones. Thanks for the tip on the tape around the motor connections. I'll give it a try tomorrow. Shaun

[Ray K.]

I've been walking around with a heli-chubby for the last 30 minutes. My TRex 450SA arrived today, and I am IMPRESSED! And this is "just" the SA.... holy cow! The build quality is incredible, the manual is amazing... it's gonna be Hell waiting fo the rest of my stuff to arrive.

This is going to be one very tall order for the FrankenAxe to fill...

-Ray

[markind]

Yep, I got an email from helihotline (Rich has taken good care of me) and I can return my bad e-board for another.

I will do this, just to have it as a spare good part, BUT

I am going ahead with the BL setup. Is possible either of those stock motors could just lock up in flight. They have a lot of hours on them but to replace them would be like 'going backwards' and I'd rather have a high tech Axe than a stoneage Axe.

Tower is giving $25 off an order of $149 or more, plus free ship, so I'll get the Ammo 3850 and a CC 9A ESC for the tail. I see a Park 370 (4100KV) on eBay for $48 free ship. I'm going with a e-Flite 20A V2 ESC, $43 delivered. I would rather pay more and have the thing run cooler. Also, the V2 is supposed to give the BL motor a more efficient timing, which should equate to less heat and longer run time.

I also found a sale on AR6000, which I need for my TREX 450SEV2, only $45 delivered. I got two. Need to plan ahead! :D CAsh flow hazard!! Ack!!

The Axe can't 'compete' with the TREX, rather, it 'complements' it. Its like having an Apache Longbow and a Cobra Gunship in the hangar. Similar, but are good at different jobs. Both fun.


Edit: Oh BTW, I found an 'almost as good as a schematic of the e-board' here:

http://www.rcgroups.com/forums/attachment.php?attachmentid=1375938

Other that the 'gyro chip' on the far right of this image, the stock Axe e-board is fairly easy to repair, if you have no other options. I will probably scratch up a diagram of this thing one day, just because.

[Ray K.]

Awesome! You'll have to let me know how that CC ESC fares on the tail setup. Also, I'm interested in how the E-Flite ESC does, too. I've had no temperature problems at all with my CC TB18, but it's always good to have comparisson information. I think that part of what I had in mind when I started this thread was that other people would post their results too, so that the ideal separations setup could be determined. My system has been based soley on research and best-guesses; I have no doubt that it's possible to do it better than I did. Let's find out, shall we?

As far as the ACP being a stablemate with the TRex, I think that the ACP's revised mission is going to be that of the new manuever guinea pig. I've been flying some pretty cool manuevers on the sim, but I've been a bit timid to try them on my only actual real-life helicopter. So I think it's gonna go like this now: Get comfortable with a stunt on the sim, and then fly it with the ACP. Upon successful completion of the stunt a few times with the ACP, I'll fly it with the 'Rex. Speaking of the ACP....

DO NOT BUY THE HELI-MAX ALUMINUM SWASHPLATE FOR ANY REASON!!!!!

I got the MicroHeli swash in the same box that the SA came in, and it's CLEARLY a better piece. Cheaper, too. And it's not purple. I've had 2 of the HMX swashes, and they were both junk... a little frustrating considering that they go for $50 or $55 a pop. If you're on the market to build a solid ACP head, do this: Get the HMX flybar cage, get the MicroHeli swash, and stop there. It's all you need- trust me. 95% of the deal with an ACP is in the setup. Once you have that right, the little bugger flies very nicely. Don't waste money on crap you don't need like I did. For one reason or another, my aluminum HMX main block EATS o-rings. I'm almost positive I'll be switching back to the stock plastic one. I said at one point that I thought HeliMax was a decent brand... not so anymore, after seeing what a REAL helicopter kit is. HeliMax SUCKS. But I still have my FrankenAxe, and I still like it, even if it took a couple hundred dollars to make it into the heli it should have been. It all works out, I guess.

BTW, I got an email from Tower today stating that my new props are in the mail. I still have every intention of experimenting and finding out what the ideal tail prop is, and rest assured I'll post about it.

Next time....

-Ray

[markind]

I placed my orders yesterday, just waiting on parts now.

Thanks for the tip on the HMX swashplate. Oh, oh, I already ordered the HMX CNC Center Hub and SeeSaw bits. I am also using their CNC Flybar Carrier. I'll see if what I end with works at all and if it indeed Eats O-Rings. I have plastic spares if they don't work out.

I'm ok with the stock swashplate for now...

[Ray K.]

Hello again, fellas.

I had a chance to do some experimentation with the new GWS 3x2 square props today, and kind of found a strange problem that I'm not sure how to interpret. I didn't change anything in terms of the mechanical setup on the tail, with the exception of the new prop. I ran the tail motor up on the bench, and it was immediately obvious that this prop makes WAY more thrust than the 3x3 scimitar prop. I ran it at full throttle on the bench for a full 2 minutes, and it also quickly became clear that the tail motor runs a whole lot cooler with this prop. So, empowered with the idea that this prop appears to be the better option, I grabbed a freshly charged LiPo and went to go fly.

I spooled the heli up, and shortly after liftoff it was apparent that my gyro gain was too high for the new setup. The symptom was obvious- the tail was oscillating pretty violently. So I set her down, and took the gain down to about 50%. Lifted off again, and had the same problem. I took the gain down to about 30%, which seemed kind of low, but the oscillation went away. So I started to maneuver the heli around a little, but the tail felt pretty soggy- specifically, it was having a hard time keeping up with sharp collective changes. Landed again, and took the gain back up to about 40%. It wagged again. By this point, I was getting a little cranky.

Now, I'm not sure what the problem is. It's totally possible that I didn't spend enough time trying to dial in the gyro gain, but it also seemed to me that gain wasn't the problem. It was almost as if the motor wasn't able to respond quickly enough to the gyro's input.. and that's a problem that had been brought up to me by Curtis (mashburncs). I could be wrong though- I'm wrong at least twice a day.

At this point, I'm going to stick with the scimitar prop, because it does work very nicely. I'm not crazy about the temperature that the tail motor gets to, but it's not a really big deal. But it kills me knowing that there's a more efficient option for a tail prop. I chose the 3850Kv motor on an outright guess, and I'm wondering if the 4110Kv motor wouldn't have been better. The higher Kv motor will have 6% more rpm per volt over the one that I have now, which means that it will be able to accelerate and decelerate quicker than the current motor. I just wonder if 6% is going to be enough of a difference... I'm going to scrape together the $25 for the new motor and try that out with the new prop, and see how it does.

In short, stay with the 3x3 scimitar props on the 3850 motor. It works well enough, and it's certainly better than stock. I'm gonna find out if there's a better way, though.

Thanks!

-Ray

p.s.- I got the 'Rex done.... just gotta fly her now!

[Ray K.]

So I just came back inside a little while ago from the TRex's second flight, which was closely followed by a comparison flight with the FrankenAxe.

As compared to the 'Rex, the FrankenAxe is indeed a great little helicopter. I should point out now that the two helis are two entirely different machines, though. In my car-guy mind, I think that the best way to compare the two is like this: The TRex is a MazdaSpeed RX8, while the FrankenAxe is a turbocharged, nitrous-swilling, lowered, sticky-tired and totally bad-ass Honda Civic.

The TRex is fundamentally a far better machine. The control response is razor sharp, it's way more powerful, and it just feels SOLID. It's a pure joy to fly- and I say that after only 2 very reserved test and tune flights. Things happen very quickly, and with very much authority on this helicopter. It's still very predictable and controllable, though. Due to this attribute, it's an easier helicopter to fly in some ways. It's downside is that it's a little intimidating- lots of noise, ballistic collective response, and the way that it sounds. It sounds like.... power.

The FrankenAxe, on the other hand, is an overachiever. I think that most of the reason that I like it so much is that it tries so hard. Don't get me wrong- the ACP is certainly a contender. While the control isn't quite as crisp, there's just as much authority at the extremes. Things don't feel as immediate, but there's just as much mojo. Think of a 3rd-grader that didn't take his Ritalin, and you're on the right track. The FrankenAxe is every bit as much fun to fly as the 'Rex, but you have to rag on it and fly it like you hate it to get the same results. The 'Rex is much more refined, and takes some finesse. The FrankenAxe takes a little more focus to fly, but it still delivers a gigantic grin. Another way to say it is that the 'Rex is a highly trained ninja, and the ACP is a lightweight cage fighter wound up on crystal meth. It's simply a different experience flying the two. It's fun the whole way 'round though, so it's all good.

Anyway, if anyone has any ideas or input on the tail prop dilemma with the FrankenAxe, please feel free to contribute... I'm a little at a loss here. Like I said, the current setup (3850Kv motor with the 3x3 scimitar prop) works very well... I'm just seeking perfection here.

Thanks guys!

Keep 'em airborne...

-Ray

[markind]

Good news, good data, good progress!! Go Ray!

I am just now sitting down to install my Park 370 into my SOFA2 (yep, Son of Franken Axe 2).

Let's see, was it the 10-tooth or the 12-tooth pinion...>?

I energized my new TREX systems yesterday for the first time, sans Gy401. Got the servos centered, next step install servo arms, ball links, etc.

Fired up the motor to a low speed with no main blades - nice. May have to back off the motor from the main gear slightly.

l8r...

Edit: Found it. Going with the 10-tooth pinion

Edit: Motor and ESC installed! The ESC installed very neatly directly beneath the motor, and does not interfere with or bind up the canopy. Next step: solder up the Dean's connectors and test the motor / ESC. Looks like I may pick up the tail motor and ESC from my LHS this week...

[Ray K.]

SOFA2!!!!! That's hilarious!!!! Awesome!

Feel free to rock the 10T pinion, but I'd like to remind you that I'm thinking about swapping it out in favor of the 12T. Flight duration will suffer a little, but after flying the 'Rex, I'd like more "pop" out of the FA. I should also note that when I switch to the 12T pinion, I'll also be upgrading to CF main blades. They'll hold up to the revs better, put less drag on the motor, reduce head inertia, and I've been getting to the point with the FA that crashes are rare. Dammit! I just jinxed myself....

So do you still intend on using the CC TB9 for the tail ESC? I'm very interested in how it works out.

Good luck!

-Ray

[markind]

Just got done ordering the final parts. CC 9A ESC should work! Looking forward to seeing how it does.

Of more immediate concern is mounting the GWS 3.25 x 3 scimitar prop to the shaft of the Ammo 3850. I want to be sure it won't pop off in flight!!! Ack!!@!@

Gotta take some pics too. She's a mess right now tho... :P

[markind]

Ok, I fired up the Park 370 and 20A ESC this morning, Here is some data. Note that the tail and Gy240 are not connected:

Idle:
.22A / 2.7W

Wildly swinging the servos around: .5A / 5.7W

Approximate Hover Speed (headspeed seems about right):

4.7A / 55W Main Motor got up to about 160 deg. F. ESC stays under 120 deg. F.

The main motor seems a bit hot for this brief test. I should probably back it off from the main gear slightly...

The ESC seems to not care what is going on and stays around 120 deg. F. This is excellent if it continues to hold true. I should hope so! Its capacity is 5 times what a hover is pulling.

I'll adjust the motor and try again...

[markind]

Hmm, well I adjusted the motor and she spins a bit more freely, and the pinion still meshes nicely with the main gear.

Still, the motor gets up to almost 160 deg. F. but it was after a much longer test. At the end of the test, 5A / 55W at hover. The ESC remained under 120 deg. F. for the whole test. Great!

Probably OK but she would do better with a heat sink for the Park 370.. Researching now...

[jeffk]

Probably OK but she would do better with a heat sink for the Park 370.. Researching now...

Don't forget the heatsink compound. It's often overlooked but it will dramatically increase the effectiveness of your heatsink.

[Ray K.]

Yeah! Jeff has it right. Make sure that you've got some heat transfer compound on there. I was able to squash the stock ACP heat sink down to fit the 370, and it only took a little bit of strategic trimming on 2 of the fins to make it work. I work in a freaking laboratory and I make data for a living... I'm a little embarrassed to admit that I haven't actually taken any kind of temperature data on the FA's 370. That said, it does seem like it gets a little hot though. It could be that it's just the nature of the beast with BL motors... it's possible that they just plain run hotter than traditional brushed motors. I dunno. It's been working without issue so far, so I'm really not that concerned.

It's kind of a moot point anyway- I think that the next evolution of the FA is going to be a "outrunner in a can" main motor, like the one on my SA. I haven't really researched any candidate motors yet, but I find myself stuck on the idea. Once again, my car guy brain tells me that more torque is always better... and gear ratios are easy to fix. I just need to start looking for parts and crunching some numbers.

Speaking of numbers.... do you guys think it's possible that the tail ESC on the FA is causing the problem I brought up a few posts ago? It just occurred to me that the switching rate on this ESC may be comparatively low. I can only assume that a higher switching rate will lead to sharper motor response... Please correct me if I'm wrong! I really don't know that much about brushless motor technology, but knowing what I do about electronics leads me to believe that if the ESC "thinks" faster, the motor will respond faster. Hmmmm.......

-Ray

[jeffk]

I dunno about your tail motor woes Ray, but here's how I plan to fix mine:

http://www.freestyle-hobby.com/catalog/product_info.php?cPath=41&products_id=207&osCsid=880058369fd1e903ebeb6ce577d50e29

Hopefully available VERY soon! :)

[markind]

Yep that's a mini TREX tail. Its the only way to get true HH. The energy is there in the tail rotor and can be re-directed much faster than a BL motor changing from one RPM level to another.

To increase the tail response to a whole 'nuther level, that's where the digital tail servos kick in. Faster frame rate, higher current means more HH counter-forcing power on the tail.

I just went through it on my TREX on the bench. No way could I have figured it out without Finless Bob's vids. I clearly felt the difference between Rate (Normal) Mode and HH mode.

The tail power was fierce. I was spinning her up secured in my hand as I often do with the Axe - no main rotor installed but I was spinning the flybar and paddles. I was too scared to get her up to half throttle - this thing is a freakin demon.

There was SO MUCH TAIL POWER the TREX was winning against my wrist's twisting of the model's direction. Scary and cool at the same time! 8^>

I had a hard time getting the DX7 to figure out the Gyro but I think I got it now. It will be useful when I go to program my new Axe Separates.

Changing motors on me already! Ack! :P

Bend the stock heat sink and it will work on the Park 370? Whoa,,, ok I'll look into it... Yep I got the goop for it.

Hey Ray K. my buddy, do yourself and all of us a favor and pick up a Duratrax or equivalent Temp Gauge. Heat is a big deal in all of these setups and you need to know how changes you make affect the op temps. :P

[Ray K.]

Hello everyone!

I've been stewing on this tail issue that I'm having, and may have found some solutions. First of all, and I'm surprised that I didn't think of it sooner, is that the tail ESC's brake function was not active. It's hard to say if it's going to make a big difference or not, but it was easy to fix. I still have to fly on it and find out if it matters... my girlfriend probably wouldn't like it too much if I went for a test hover in the living room. Next, I did some research on the SS8 ESC and some other appropriate tail ESCs and found some interesting information- the switching frequency on on the SS8 is 8.5 kHz, while at least 2 of the other options have switching rates of 11 or 12 kHz. So indeed, the SS8 isn't as sharp as it could be. Instead of just going right to the motor and swapping it out for the 4110 kV option, I think that it would be smarter (and easier) to try a different ESC first. The other ideas that I had were that I could adjust the rudder EPA in the radio, and I could shorten the tail boom by a couple inches- the consensus seems to be that a shorter boom offers sharper tail response. These last two ideas don't seem to be as good as the ESC idea, but I'll probably try them anyway.

At any rate, I'll post whatever results I get from these changes as soon as I know.

That belt conversion looks like a winner! For $100, I'm not sure about it though. If I would have bought all the right parts for the brushless / direct drive tail the first time, it would have cost about $50... Half the money for what could potentially be a comparable tail performance-wise is hard to argue with. I understand that the true variable pitch tail will be more responsive, but let's not forget that this an Axe CP we're talking about- not exactly a high-performance aerobatic helicopter. I feel that while it's definitely cool, the belt tail may be overkill considering that a DD tail offers very good performance for this type of heli. I'd sooner take that $50 difference in cost and put it toward replacement parts.... but that's just me. Maybe the other reason that I kind of reject it is that I feel like I'm onto something with this BLDD tail, and I don't want to stop until I've got it perfected.

markind-

I know I need to get a thermometer. I guess the only reason that I haven't is because I have so much equipment available to me at work... IR meters, thermocouples, data acquisition computers... It's a little stunning that I haven't taken advantage of that stuff, though. I don't know why. I think I'm just lazy. Maybe one of these days I'll do a full 20 or 30-channel instrumentation package on the FrankenAxe and record temperatures, amperage draws, 3-axis fuselage acceleration, and rotor rpm data. Or maybe not. That seems like a lot of work, especially when I'm not being paid to do it... but it would be fun, and would no doubt make some useful data. I wonder if HMX is hiring evaluation technicians....

Anyway, I attached a photo of the "fleet"... enjoy!

-Ray

[AirJet Aviation]

Hey Ray,

With all that equipment at your work we should build our own home built heli!!!! I forgot, which Swash servo's are you using on your AXE? Are the stock one's good or bad? At my RC experience level, which is begginer at best, should I spend the money on a DD tall or should I wait awhile? I did buy the MH Swash and MH flybar cage for both my Blade and AXE, I just wanted a little bling. I think that is far as I am going to go one these little guy's.

Larry
FIRST HOVER - " the most fun you can have with your clothes on"

[Ray K.]

Larry-

I'm using Hitec HS55's on the FrankenAxe, and I like them a lot. They're certainly better than stock, with better transit speed and more torque. And they cost less than the stock HMX servos- about $13 a piece at your LHS. I used them because I had a stock servo fail, and I wanted better servos anyway. They're great!

As far as the DD tail, all you really have to do is spend about $4 on props. Easy, huh?! Just pull the stock tail rotor, rotor shaft, gear, and bearings, and then pull the pinion off of the stock motor (I strongly recommend using a pinion puller!). After that, just reverse the negative and positive leads on the tail motor connector, press on the new prop, and you're rockin' like Dokken.

And with the aluminum head parts, you got all the right stuff and nothing you don't need. Good job!

Build my own helicopter? I'd love to! Problem is that my model helicopters and my other obsession- my car- are already putting me in the poorhouse. I have a hard time coming up with $68 for me and the old lady to have a night out, much less 68 large. One day....

-Ray

[Ray K.]

To make a long story short....

The FrankenAxe is temporarily going to be re-configured as a brushed-tail Axe. I had a pretty gnarly crash because of my impatience on an untested BL tail configuration, and I have some bench testing to do before I fly with it again. But the answers are coming.... eventually. My little sister is getting married this weekend (damn I'm getting old...), and I won't be around for a little while. I still have some details to work out on how exactly to test the BL tail, but I intend on getting to the bottom of this. I'm not giving up!

In the meantime, I'm going to use a GWS EDP-50XC motor as a stand-in for the tail, in conjunction with my trusty ElectriFly C7 ESC. I chose this motor because they only cost $10.50 a piece (allerc.com), and they're known to be suitable replacement tail motors for Axes and Blades. I got 2 of them, but I hope to have the BL situation figured out before I burn out the first one. I'm definitely sticking with the DD setup, because I truly feel that it has better response and authority than the stock tail setup. I'm going to keep using the 3x2 square prop, but if it doesn't work I'll just switch back to the 3x3 scimitar prop. One of them will work!

The TRex is flying very, very well. I LOVE IT! I'm not nearly as brave with it as I am with the Axe, for a couple reasons. First, I'm not as familiar with the "personality" of the 'Rex as I am with the ACP, and second, the FrankenAxe's mission in life has changed. It's my "booty chopper" now. Now that I have 2 helicopters, I'm suddenly not nearly as afraid to crash the ACP. So it's mission as a trainer has been expanded- not only is it a hover and basic maneuver trainer, it's become an advanced maneuver trainer also. It's true that the 'Rex is the better helicopter, but I've actually gained appreciation for the Axe. It's easy to fix, more difficult to fly, and small enough to not be intimidating. That, in my mind, makes it an ideal trainer. If I can pull it off on the Axe, I can fly it with the 'Rex easily- assuming I can get over the intimidation of it. And if I crash the ACP, I have a mountain of spare parts to fall back on. The only reason that I've been down for so long is that Murphy was in full effect on my last crash... meaning that the one or two parts that I didn't have spares of were the ones I needed. Typically, I've got the FrankenAxe airborne again within 30 minutes of an "incident".

Anyway, I'll let you all know how the new tail motor works with a DD tail... parts should arrive tomorrow or Thursday. I've got the week of the 27th off of work, so I'll be able to make some good progress with the FA and it's new 12T pinion... assuming that the weather cooperates with me.

Later!

-Ray

[markind]

Ray you and I are on the same hobby island out here in the sea of unknowns. My own TREX is well on its way to becoming ready for its Maiden. I just got done with HS65MG servo installations. PERFECT! I got the arms to the swash straight as lasers. This after re-doing it 5 or 6 times... :\ I did not shorten any of the wires, as mentioned in the Finless Bob vids. Although this saves weight, its a lot of soldering and not critical for basic flight so I will postpone this big job. Instead, I neatly packed the wires inside the frame(s) so that the whole thing is pretty darn clean, and the wires are clear of all moving parts. I found a sweet spot for the AR6000 install and am pleased with the results and testing so far.

I got out my digital calipers and got everything to spec and I got the swash plate pretty level at the magic 50% stick position. Still fine tuning...

But now I got Axe parts, so its off with the stock Axe tail motor - GOOD RIDDANCE!! I will install my CC9A and the Ammo 3850, but I will keep it geared for its first tests. I'll mess with DD later... I just want smooth basic flight!!!

Data and pics coming soon.

[Ray K.]

Just be sure to activate the brake on the tail ESC!!!! That's actually pretty vital to the tail's performance.

Glad to hear that the SE is coming along... I share your excitement! You're gonna love it on it's first hover! My blade tracking was WAAYYYY out on my maiden flight with the 'Rex, but it still flew very nicely. You're gonna love it!

-Ray

[markind]

BOOYAH!!!

After a couple of hours soldering and routing wires, she LIVES!! I also had to pull the little brass pinion gear off the stock motor, and put it on the new Ammo BL tail motor. I asked my LHS about getting spare brass pinion gears, but all he had were GWS pinions and the 1.5mm I.D. size they carry do not have the right 'tooth pitch' and would not work (they looked too small on the O.D.). The guy said getting 1.5mm pinions for that Axe tail gear would be difficult.

Sound like Helimax wanted to something 'proprietary' so it would not be so easy to avoid paying them $25 for that cheap-@$$ stock tail motor. Grr.

Fortunately the BL tail motor is indeed spinning in the correct direction!

Rudder control works! Gyro is responding!! EXCELLENT progress!!

Now for some debugging!

I have to figure out how to set the brake on just the one ESC. Since they are now both wired for power, I have to find a way to program just the Tail ESC and not mess with the main ESC.

Also, the tail motor would not shut down unless I gave full left rudder stick. Even the Throttle Hold switch would not shut it down. Needs a tweak somewhere...

Very exciting and fun! Can't wait for the re-Maiden! :flamedevil

[markind]

Ok, progress!

I unhooked most of the wiring again, and hooked up a temporary test setup that allowed me to program the tail ESC for Brake On, and if necessary, reverse the motor. Kewl.

Since the wiring was mostly undone anyway, I went ahead and installed an e-Flite 20mm heat sink on the Park 370 motor. Fits perfectly in the Axe!! White grease is in there - got it just perfect and not too much mess.

I just got down re-wiring everything and did another bench test. Here is some Tail Motor data:

At Idle (no spin) .21A / 2.6W (some of this is Servo Idle current).

At Estimated Hover RPM:

1.5A / 18W

Man!! My 9A ESC is WAAAYY overkill. It had better run cool, dammit!!

Maximum:

2A / 24W

This should be enough for a crazy-fast right yaw rate. It gives quite a tug on the tail! Enough to flex it!

Right on.

BUT, the darn thing will still not shut down all the way when the throttle stick is all the way down, as in 'after landing'.

How did you fix this? After I fix this, I am ready for putting the training gear back on, and doing some hopping and sliding tests in the big clubhouse on the slick linoleum floor. This will allow me to trim out the new tail without danger of crashing.

I may not go DD on the tail if this works as well as I think... :Stay

[Ray K.]

As far as the whole continuing to run thing, I just kind of dealt with it on mine. It wasn't really enough of an irritation to me to try to solve. For the programming part, I just unplugged my main motor from it's ESC and left the "rudder" channel set up as it was intended. Then, by using full right / full left rudder inputs, I was able to program the ESC.

I'm not sure why BL ESCs have this run-on issue and standard ESCs don't. Strange.

Anyway, let me know how it does once you start to really fly hard on it. Mine appeared to be okay until I really started loading the tail up and pushing it hard... but I was also using a DD setup with a "mild" prop. If this brushless tail system appears to work nicely without the DD, I may do that in the future too. I just want to see if I can't get it to work properly with the DD first.

Good deal!

-Ray