Axe CP separations and setup journal

[Ray K.]

Okay, so I got the bright idea to run my Axe CP in separations after encountering some problems with the stock parts.

I've decided to go with the all-aluminum head, and there are a few things that I would like to point out for anyone else looking to do the same. I ordered all of the parts, but the mainblock and blade grips are on backorder. It turns out that you must have the CNC mainblock in order to use the CNC slider and seesaw- the aluminum unit will not work with the factory plastic mainblock. So I'll have to wait before I can install that. Also, it should go without saying that it's pretty much required that you apply loctite to the aluminum parts' ball link screws. All of the ball links on my swashplate were hardly more than fingertight when I got it. The flybar carrier, however, works just fine with the stock seesaw, so I went ahead and installed that.

When I completed installation of the swashplate, I went on to make sure that it sat level. In the process of doing this, I checked for freeplay and binding by running the radio and putting various combinations of collective and cyclic inputs on it, and discovered that the anti-rotation pin on the swash was actually "topping out" in it's keeper under full negative collective and full forward cyclic. Not good.

I remedied the problem by making all of the swash links about 2mm shorter than HeliMax's recommendations, and took the pitch links in by a similar amount to get my pitch back to zero degrees at center stick on the collective. I found that there's a "sweet spot" in the link setup, and I was able to make it so that the swash has total freedom of movement under all input conditions. It works fine now.

I also installed a Futaba GY240 in conjunction with an Electrifly C7 speed controller for the tail motor. HeliMax's website recommends a C12 speed controller, but the C7 works just fine, and doesn't even get warm to the touch after a run- even under the canopy and doing nothing but hovering with some piros. Just make sure that you've got the jumper on the speed controller set for "LiPo", and not for nickel batteries, even with the stock NiMH battery pack. The output voltage from the stock NiMH battery is high enough that the C7 will not function unless it thinks it's running LiPo. I've been running it this way for a little bit now with no problems. The gyro works awesome, and was certainly a worthwhile upgrade.

I also have a Park 370 BL Inrunner with a CC Thunderbird 18 ESC that I'm going to install as soon as my backordered DX7 arrives. I suppose that it's possible to run a separated BL setup with the stock 3-in-1, but it would take some crazy splits and a lot of soldering to get done, so I'm just going to wait until the radio arrives. I intend on using the 10T pinion with the motor. My LiPos are also on backorder, so there's going to be a whole other round of mods that I'm going to do.

So I'm running a partially separated Axe CP for now, but I'll be sure to fill you guys in on the rest when all of my goodies are finally here. But to this point, the swash and gyro upgrades have gone well, and have certainly made a difference for the better.

Until next time...

Ray

[USNRIS]

Ray,

I've fried the 3-in-1 on my Axe CP and am thinking of just biting the bullet and getting a Futaba 7C or the new FASST (instead of sinking $85 on a new 3-in1). (I was already thinking of going the separated route anyway) I already have the GY240 and C-12 for the tail rotor. I'm gonna be sticking with the stock head. Can you tell me (1) what the swash type setting should be - is it a 1-s or 3-s, and (2) which servo plugs into which channel on the receiver? If you have any diagrams for the separated setup, that'd be great! Thanks for your help.

Jeff

[Ray K.]

Aw, jeez.... I have no idea!

I have to admit that radio setup is the only remaining great mystery about my separation project. I have a DX7 on backorder with an AR6100 Rx. I can't really say if the setup procedures or vocabulary are the same between a DX7 and your radio, but when I begin that process in 2 or 3 weeks I'll be sure to tell you (and everyone here) everything that I did on my setup. I guess as far as the servo channels go, I would start by duplicating the factory setup, and if that doesn't work right, take a long hard look at some magazine photos or any other photos you can find of other people's setups and see if you can't reverse-engineer it. For my setup, I'm banking on the hope that the manual that comes with the radio is going to have all (at least most) of the answers. If it doesn't, I'm going to be asking about a zillion questions!

Now... you said that you fried your 3-in1. How? I noticed that the battery leads had very poor solder connections to the PCB on my Axe. I've had to repair both the negative and positive sides once each. I'm wondering if the company that produced those PCBs isn't exactly a high-quality outfit. Contracts typically go to the lowest bidder, right?

Again, when I get my radio and start on my setup, I'll let you know in great detail what I end up doing. That's what web forums are for, right? That's also why I started this thread.

I'll also post some photos of my Axe when it's done, including detail shots of the mod that I'm going to have to make to the fuse and canopy to shoehorn in the 1250 mAh LiPos that I ordered- but that's for the next post.

Take care, and good luck!

Ray

[USNRIS]

Kinda feel like a dork admitting here, but when I was installing the GY240 and C-12, I plugged the motor connector from the speed control into the 3-in-1 instead of the motor wire plug... smelled the frying electric smell, but the board was gone before I could disconnect. Just one more expensive lesson in life. I've contacted Helimax to see if they have any separation setup instructions (and to see if they'd comp me a new 3-in-1 (never know if you don't ask, huh?)). once I get back in the air, I'll also post setup instructions here.

Later.

Jeff

[Ray K.]

Ouch!

Don't feel too bad. I've made several careless mistakes also. Like not watching my wire management and sawing my tail motor leads in half on the main spur gear. Or the time I went to adjust the gyro gain on the 3-in-1 and accidentally changed the wrong pot.

85 bucks seems like a lot to replace something that's not even really that great to start with. I'd just use it as an excuse to run separations!

Good luck with your setup, and I look forward to comparing notes when we're each done.

Ray

[USNRIS]

Well, a bit of good news! Helimax got back to me (EXCELLENT cust. svc. I must add) and advised that, since I already had the GY240 and C-12, I could just replace the 3-in-1 with an Electrifly C-25 speed control. Only one minor error on their part - the guy was referencing where to plug in the single orange wire from the C-25. No such thing... Anyway, got everything installed and am back up in the air again! Still flying with the stock radio/rcvr while deciding on a new radio. Much easier hovering with the HH gyro! I can get through a whole pack now.

BTW - have you seen the flat-bottomed plasti-blades on the Tower site? I have a set on my Axe and they work pretty well. Seems like the head speed is a bit lower than with the stock woodies, but the increase in lift is pretty substantial.

Oh yeah - one other tip that I read about else where that REALLY works. I took off the heat sink from the main motor and used my Dremel to cut away the parts of the heat sink that cover the cooling holes for the motor. I could really tell the diff in motor temp afterwards.

[Ray K.]

That's good to know about the heat sink- I was beginning to get a little concerned with how hot my motor's been getting.

That's also good to hear about the 3-in-1... the only reason that I was keeping it around was because I was under the impression that all of the CCPM mixing happened somewhere in the 3-in-1. Sounds like I'll be doing my BL upgrade right away then! My LiPos came from the nice man in the big brown truck today, so it looks like I'll be doing more tinkering than flying tomorrow. My stock NiMH battery pack is already beginning to show signs of decreased performance. I'm not impressed. In hindsight, I would have bought some LiPos the same day I bought my Axe!

And what the hell is that mystical orange wire for, anyway?!?!

I have indeed seen those plastic flat blades, and seriously considered getting some. I ended up not doing it for 2 reasons: First, I saw staying with the fragile woodies as motivation to not dip the blades, and second, I figured that learning to fly on symmetrical blades would ultimately be one less transition that I would have to make later. More difficult? Probably. But I tend to have a hard time re-learning something once I'm comfortable doing it a certain way, so I just stuck with the stock woodies.

Now that I think about it, I may still wait to do the rest of my ups. It's gonna be a big job, as all of the wire routing is going to be totally different. I'm going to put my ESCs in the rear part of the fuse to help offset the weight of the 1250 mAh batteries that I got. And I'm going to have to split the fuse apart (again!) to remove the stock motor.... it's a lot of work. I'm thinking if I just wait until the rest of my CNC head pieces arrive, I'll do it all then in one big horrible experience. Swapping the Rx at that point will be a cinch, because I intend on keeping the Rx in the same location as stock.

What have I gotten myself into!?!?!

Later-

Ray

[Ray K.]

I ended up doing the full separations package (less the radio and a couple CNC head bits) last night, and I'm still giddy.

This thing flies AWESOME!

Crazy power, excellent duration (about 12 minutes on it's maiden flight), vastly improved control because of the higher headspeed.... it's a great helicopter now!

I'm going to be doing a detailed writeup very soon, and I'll have some photos too. It's funny, because I was SO worried about being excessively nose-heavy with my huge LiPo pack, but it turned out I was pretty tail-heavy after all. I'm most likely going to tear out the electronics and move them about a little, but it's flying for now. That, and my wire management was less than ideal, and I used way more electrical tape than I should have. Bottom line, it's ugly, and I'd like to clean it up before I take photos.

But it's coming soon...

Ray

[USNRIS]

Sounds like you're on your way! You getting the higher headspeed out of the new BL motor alone, or did you also change out the pinion? Also, what lipo are you running? I've got a TP 1320 and I'm not happy with the way it fits in the battery bay. I have to put it in vertically and I've noticed that once you get it cinched down with the rubber band, the lower part of the bay has put a couple of little dents in the battery case. I don't think that's any cause for alarm - the battery doesn't overheat or anything. But I still watch it extra carefully. I might do a little mod on the frame to see if I can get the battery bay a little wider.

Have you been able to fly outside yet? It's been fairly windy down here in Tampa so I've been stuck hovering in my apartment living room - and only 3-4 feet off the deck at that. Barely enough to get out of the rotorwash.

Be sure to lemme know when you get your new radio installed!

Jeff

[Ray K.]

I think that the headspeed is a combination of the higher voltage, BL motor, and the pinion I'm using. I've got an E-Flite Park 370 Inrunner, 4100 Kv. I'm using the 10T pinion with it. I calculated that to be 2950 RPM under full throttle and no load, so everything should be fine in real-world flying conditions.

For the LiPos, I'm using ElectriFly 3s 1250 mAh 15C packs. Tower had a buy two deal, so that's what I did. I had to cut away the battery tray from the fuse and stand the battery on edge to get it to fit, and I also got crafty with some CF rod, fuel tubing, and epoxy to make a new battery support. I'll be sure to take some good photos of exactly how I did that. It's working okay so far, but I did have to re-glue one of the rods- it was only poor surface prep that caused the epoxy bond to fail, and I don't expect any more trouble. I also had to modify the canopy a little to make it work, and that involved dropping the nose of the canopy by making new lower mount holes. It took about 2 minutes to do, it fits perfectly, and it lends a more aggressive appearance to the heli, so it's all good.

I did fly outside today for the first time, and it was a little too windy for me, so I had to cut the flight short. It was simply a matter of my lack of experience- I'm sure a better pilot would have been fine. A big gust of wind came up and caused the heli to climb about 20 feet, and took it about 50 feet away from me. It spooked me a bit, but I managed to bring her back down in one piece. I'm going to try again tomorrow, I think. Just depends on the wind. Otherwise, I'm going to continue flying at my work- not much altitude available, but plenty of lateral space. I feel like I need to get more comfortable flying in all orientations before I try to fly in the wind again. Well, at least wind like we had today. It was certainly more than just a breeze! The heli itself coped with the wind just fine, and once I'm a better pilot, it'll be fine. I'm also sure that as the months go by deeper into summer, the wind will calm down quite a bit.

Ray

[USNRIS]

20 ft up?!?! That would've done more than spook me a little. I'd be cleaning out my shorts! I took some photos of my Axe. You can see the mod I did on the motor heat sink.

[Ray K.]

At last, here it is:

Before I dig into exactly what I did for the separations, I would like to point out that I upgraded to Hitec HS55 servos because they're a bit smoother and more powerful than the stockers. I also made my own servo horns with super-tight holes for the z-bends and lubed them up with a little petroleum jelly. They don't bind, but there's no slop in them either. That mod alone was actually one of the more profound that I did in terms of control. I also lowered my swashplate by 1.5 or 2 mm or so, because I found that the anti-rotation pin was topping out in it's keeper under full forward cyclic and full positive collective. I managed to find a sweet spot in the length of the links that allows full freedom of movement under all input conditions. Please note that it's necessary to shorten the pitch links by an equal amount in order to preserve zero pitch at center stick.

I'll start with the wiring schematic, then discuss each part:

http://i37.photobucket.com/albums/e72/klittlesister13/stuff/ebay/heli/Wire.jpg

BATTERY:
ElectriFly BP1250 - 3S 1250mAh 15C LiPos with female Dean's Ultra Connector and wired for balance charging. I chose these because Tower Hobbies had a discount deal if you bought two, and the 910mAh bricks were on backorder- and I'm impatient. They weigh 106g, which is actually 8g lighter than the stock NiMH battery pack. Because of the unusual size and shape of these batteries, I had to modify the fuse by cutting off the battery tray tabs in order to make enough room for the battery to stand on edge. The tabs themselves are not a structural member of the fuse, so there was no harm in tossing them. I also added two "prongs" made out of CF rod and covered with fuel tubing (total cost: about $3). These prongs were then epoxied to the fuse in the little pocket between the upper battery compartment tabs and the forward electronics tray support. I was having some trouble with these, so I ended up drilling holes into the supports above and below the prongs, and then used zip-ties to secure them, and then filled the whole mess up with epoxy. It works fine now. Now, the battery rests on the skid support, and is snugly held in place by the prongs with a rubber band going around it. I also had to modify the canopy to fit around the battery by lowering the nose a little. That was just a simple matter of making new lower mount holes (about 7mm above and 3mm forward of the stock holes), and cutting away some of the lower part of the canopy so that it would clear the skid supports.

http://i37.photobucket.com/albums/e72/klittlesister13/stuff/ebay/heli/fusemod.jpg
http://i37.photobucket.com/albums/e72/klittlesister13/stuff/ebay/heli/batterymount.jpg
http://i37.photobucket.com/albums/e72/klittlesister13/stuff/ebay/heli/leftoverall.jpg
http://i37.photobucket.com/albums/e72/klittlesister13/stuff/ebay/heli/canopymod.jpg
http://i37.photobucket.com/albums/e72/klittlesister13/stuff/ebay/heli/still2.jpg

GYRO SETUP:
I pretty much followed HMX's instructions to a T, except I used an ElectriFly C7 ESC instead of a C12. The tail motor draws very little power, and even my C7 is overkill. I've heard of folks using GWS 2A ESCs with no trouble. I used a Futaba GY240 gyro as suggested, and was able to find one online for $100. Not bad for a HH gyro! I have my gain set to about 70%, and that seems to be about perfect. The wires coming out of the gyro face the right side of my Axe, for the simple reason that it simplifies the wire management. The Rx lead from the gyro goes into Ch. 4 on the Rx, and the servo lead goes to the C7. It's VERY important that you pull the red wire's pin out of the ESC connector! You'll smoke your gyro if you don't! I even went so far as to trim that wire back all the way to the ESC, and then capped it off with some heat shrink tubing. I mounted the C7 as far forward as I could on the right side of the electronics tray for balance purposes. In addition to the Dean's Micro Connector soldered to the output leads of the C7, I put a Micro connector on the input leads as well to make maintenance easier. The blue wire from the C7 is the negative lead, and the white wire is the positive. That connects to the tail motor extension wire the same as it does in the stock configuration. I kept the stock tail motor/rotor setup as is... for now. I'm thinking about doing a DD (maybe even BL) setup, but I'll write about that when I do it. Further setup and initialization instructions can be found at HeliMax's website (www.helimax-rc.com).

http://i37.photobucket.com/albums/e72/klittlesister13/stuff/ebay/heli/tailesc.jpg

MAIN MOTOR AND ESC:
For the motor, I used an E-Flite Park 370 Brushless Inrunner 4100Kv with the 10T pinion. In this configuration with LiPo power, you'll get a headspeed of 2870 RPM at full charge (12.6v) and full throttle, and 2528 RPM at nominal charge (11.1v) and full throttle under no load. Under real-world flying conditions, it's likely a couple hundred RPM less, but it's still right where you want it. I used the stock purple Axe heat sink on the motor, but it took some of the old kung-fu grip to squeeze it down into shape to fit the motor. I also had to trim the upper corners of the outermost fins on the heat sink because they were interfering with the fuse slightly. A little bit of Dremel love, and the job was done. The motor fits perfectly, and after setting the gear mesh there's still room to spare for adjustment. For the ESC, I went with Castle Creation's Thunderbird 18 Brushless Controller. It's relatively inexpensive, ready to go out of the box, simple to use and adjust, small and light, and Castle has a great reputation. There's no way that the motor can draw enough power to overwhelm this ESC, and it's been hardly warm to the touch after a flight. There was literally no setup required on this unit- truly plug and play. I mounted it in the lower aft portion of the fuse, so that it would be nice and close to the motor, and have plenty of airflow over it. Putting it there also made battery connection easy, and it was also part of keeping the Axe balanced.

http://i37.photobucket.com/albums/e72/klittlesister13/stuff/ebay/heli/heatsink.jpg
http://i37.photobucket.com/albums/e72/klittlesister13/stuff/ebay/heli/esc.jpg
http://i37.photobucket.com/albums/e72/klittlesister13/stuff/ebay/heli/esc2.jpg

LOW VOLTAGE WARNING SYSTEM:
I used an HR POLY-X warning system here. It's not a necessary piece of equipment, but I'm the type of guy that likes peace of mind and cheap insurance. Axes don't have the ability to autorotate, so it's good to know when you're running low on juice. That, and I don't want to ruin my LiPos by running them too low. I picked this unit because it's got a visible and audible alert. I got this from my LHS for about thirty bucks. Much like the main ESC, this piece was ready to go out of the box, with no adjustments or setup required. Just like the tail ESC, I put a Micro connector on it to make working on the heli easier. I mounted this in the same manner that I did the tail ESC, only on the other side of the tray. In the pic, the black cylindrical thingy is the speaker for this system.

http://i37.photobucket.com/albums/e72/klittlesister13/stuff/ebay/heli/batterywarning.jpg
http://i37.photobucket.com/albums/e72/klittlesister13/stuff/ebay/heli/rxtopview.jpg


All in all, I would have to call this a very successful project! It's not very often that something I built works exactly the way it's supposed to the first time, but this one did. And I've got to say, my Axe is a whole new machine now! Plenty of power, great flight duration (12-15 minutes), and improved cyclic and rudder control. If any of you have any questions, please feel free to ask, and I'll answer them as best I can.

Good luck!

-Ray

p.s.- I'll be doing my DX7 setup soon, so keep watching if you're interested!

[Ray K.]

Okay, I got my DX7 the other day, but it's going to be a little bit before I can post about it. They sent me the Airplane version instead of the Helicopter version, and I had to send it back all the way across the country (Washington state) to exchange it. I sent it out the Friday before Memorial Day, so I'm expecting it back pretty soon. I did notice that the AR6100 Rx is freaking TINY and very very light. So small and light, in fact, that I'll probably have to re-wire the whole bird and re-position some things to maintain balance. My current configuration is a little tail-heavy, and the new Rx will probably make it unacceptably tail-heavy. So I think that the main ESC will probably wind up under the canopy, and I may also move the low-voltage warning to the back of the fuse. Don't know exactly yet, but I'll take some photos of how it ended up.

[USNRIS]

Ray - you up and flying with the DX7 yet? I just picked one up today. So far, I've got all the servos in the right channel and going in the right direction (had to reverse a couple). I'm really curious as to what your throttle and pitch curves are set to. Any other settings would be helpful too (seems like I've got way too much throw on the collective - the swash bottoms and tops out on the stock DX7 programming).

Hope all is well...

[USNRIS]

As a post script to the above.... also seems like there is WAAAAAAYYYY too much expo dialed in on the cyclic. On the old stock radio, I had to make minimal stick deflections to get he control input I wanted. With the DX7, I have to move the sticks really far from center. Thanks bud!

[Ray K.]

THE DX7 IS UP AND RUNNING!!!!! (finally)

It took me a little while to figure out how to bind the Rx (AR6100), but once that was done, it was a piece of cake. I was going to use the servos that came in the combo pack for my radio, but it turns out that they wouldn't really mount right, and the horns wouldn't jive with the swash links. So I just stuck with my Hitec HS55s, and they're working great. After several test flights, this is the recipe for my secret hot sauce:

CH. 1: Main ESC (Normal)
CH. 2: Left servo (bottom rear) (Reversed)
CH. 3: Front servo (Reversed)
CH. 4: Gyro (Reversed)
CH. 5: unused
CH. 6: Right servo (top rear) (Normal)

SWASH MIX:
3 servo / 120°
Aileron: +100% (to enhance cyclic response)
Elevator: +100% (to enhance cyclic response)
Pitch: +40% (to relax collective response)

THROTTLE CURVES:

Normal Mode:
Exponential Off
Point L: 0.0%
Point 1: INH
Point 2: 50.0%
Point 3: INH
Point H: 100.0%

Stunt Mode 1:
Exponential Off
Point L: 100.0%
Point 1: INH
Point 2: 50.0%
Point 3: INH
Point H: 100.0%

Stunt Mode 2:
Identical to ST-1

PITCH CURVES:

Normal Mode:
Exponential Off
Point L: 27.0% (gives me about -4° on my setup)
Point 1: INH
Point 2: 50.0% (makes 0° on my setup)
Point 3: INH
Point H: 100.0% (makes about 11° on my setup)

Stunt Mode 1:
Exponential Off
Point L: 0.0% (about -11°)
Point 1: INH
Point 2: 50.0%
Point 3: INH
Point H: 100.0%

Stunt Mode 2:
Identical to ST-1

THROTTLE HOLD:
Identical to both stunt modes, and the throttle is set to 0.0%. I have it activated by the T-Hold / Rudder D/R switch. It doesn't really matter if this is active or not with an Axe (because they can't autogyro), but I use it more as a "set up" mode than anything. Only because I'm lazy and don't like to disconnect my motor from my ESC every time I want to check my settings or make an adjustment. It's much easier to just flip a switch.

REVO MIX:
All values set to 0.0%. If I didn't have a heading hold gyro, I'm sure that I would have used this feature, but the GY240 does it's job just fine.

PROG MIX:
I have no use for these yet, so they're all INH.

TIMER:
Mine's a count-down set for 12 minutes.

DUAL RATE & EXPONENTIAL:
I'm set for Linear across the board, as well as all dual rates being set to 100%, which doesn't really matter, because all D/R switches are set to INH. I tried a little expo at first, and really didn't like it. All AUTO D/R and Expo settings are INH.

TRAVEL ADJUST:
All are set to 100%, except for Aileron and Elevator, which are each set to 110% in both directions. Between the swash mixes being set to 100% and the end points at 110%, I got the amount of cyclic travel that I want.... for now. I'm thinking that I may actually take the end points out to 115%. I got so used to having pretty sharp response with the stock radio that it felt funny to me to have the cyclic so vague.


The actual process of the mechanical setup on my Axe was pretty straight forward. As soon as I got the Rx to work with the Tx, I simply centered the gimbals (no trim), and set my servo horns as close to 90° as I could. Then, I used sub-trim to make them exactly 90°. From there, I adjusted the length of the swash links to make it so that the flybar slider was centered in it's slot on the rotor hub- keeping the swash level, of course. At that point, I adjusted the pitch links to get the blade pitch as close to zero as I could with the swash and slideblock in that position. Finally, I went back to the sub-trim screen and fine-tuned the swash height to get exactly 0° pitch at 50.0% stick. With the aluminum head (I decided to keep the plastic blade grips, though), it appears that +/- 16° of pitch is available. I set mine up for 11° in either direction, and it works pretty well. It's very responsive, and I did that on purpose to force myself into developing better collective management skills. Some people may find it a little sharp. As a side note, my throttle curves with the Park 370 make the headspeed *much* higher at hover that it would be with the stock motor. I noticed that there is hardly any penalty in flight duration, and the higher headspeed seems to make for a more stable bird. It also seems to sharpen the cyclic response a little.

This setup is probably going to change as my skill level improves, but it's a basic and easy setup that works well enough for now. It's likely that I'll be giving it more collective range as I become a better pilot, and it's not hard to imagine that I'll dial in some more cyclic authority also.

I ended up having to move the main ESC under the canopy after all. I'll take some photos of how it all turned out, and I must say that I'm much happier with the wire management this time than I was with the wire in the photos I posted earlier. I guess last time I knew I was probably going to be moving some stuff, so I didn't try very hard to make it pretty.

If you have any questions, please feel free to ask. I'm all about trading ideas and information!

Good Luck!

Ray

[mashburncs]

Ray K and USNRIS,

I am a brand new member, new to heli's, and have an AXE CP on the way. I am currently training on a simulator. Both your setups appear to have replaced the stock 3 in 1 E board, kept the stock receiver, and added seperate ESCs and HH Gyro. My biggest question, which I cannot get a straight answer to from Helihotline, is whether your setups will work with the stock 5 channel transmitter that comes with the AXE CP. My other question is, with the stock transmitter, what do you think the stock throttle and pitch settings are with stick in the middle, and at both extremes, in normal mode and in idle up.

Thanks,

mashburncs

[Ray K.]

Welcome!

The stock transmitter works just fine, so long as you keep the stock receiver, too. I flew mine like that for a few weeks while I was waiting for my DX7.

As far as the pitch and throttle curves with the stock radio, I'm not really sure what they were. I was in such a rush to install the new radio that I didn't measure them! As far as the pitch curves go, I would say that they're probably in the neighborhood of -3°/+10° in normal mode, and -10°/+10° in idle up, with 0° at center stick for both. The throttle curves are likely to be 0% at low stick, 50% at center stick, and 100% at high stick in normal mode, and 100% low, 50% center, and 100% high stick in idle up.

I'm not certain of any of these numbers, but that's how it appeared to be on my radio.

Good luck, and welcome!

Ray

[mashburncs]

Ray K,

Your estimate of the throttle and pitch curves are plenty good, and are just what I was looking for. Also I needed a confirmation that separations would work with the stock transmitter and receiver without the 3 in 1 E board. Helimax could not give me any type of useful answer. They did not appear to know whether the stock transmitter would work without the E-board, because they were unclear as to whether the pitch and throttle curves were controlled entirely by the transmitter or were mixed in the 3 in 1 E board.

I still have many hours on the simulator before I dare try to fly the model. Flying the simulator is very difficult, even with no wind, as the controls seem very sensitive. I know that I can reduce the gain on the simulator to reduce the sensitivity of the controls, however, I really don't know how sensative the model is, so I don't want to make the simulator to easy to fly.

Thanks very much.

Curtis

[Ray K.]

Curtis-

I feel your pain with the sim thing. I, just yesterday in fact, finally got around to getting a sim. I'm running Reflex XTR, and as far as I can tell it VERY closely approximates what you can expect in real life. I was stunned at how "real" it is! I'm using about 15% exponential on the aileron and elevator controls, and that seems to be pretty close to the real McCoy.

You did right getting a sim first. I got the heli first, figuring that baptism by fire would be my best bet. I can tell you right now that I would have saved a few hundred dollars in repair costs by getting a sim at least at the same time I bought the heli. I think to this point, I've killed 8 sets of blades ($20 a set), 4 tail rotors ($6 each), a fuselage ($25), a tailboom ($15), countless blade grips ($4 a set), a flybar, 2 flybar carriers, 1 set of skids, and many other little parts.

On the other hand, though, there's nothing like flying the real heli. If you can hover on the sim, it's time to try it for real. There are other factors that go into flying the real thing that a sim can't.... simulate. Like sweaty palms, a sudden mechanical failure, a bug in your ear that won't go away, a sudden and powerful gust of wind... the list goes on. I don't regret flying my Axe one bit. Sure, I could have saved some money, but experience isn't free.

Don't be afraid to crash. It's going to happen whether you want it to or not- it's just part of being a heli pilot. As you become a better pilot, you'll crash less, and that's why sims are so valuable- it substantially reduces your repair bill. But there's also something to be said for actually working on your heli. You'll have a better understanding of how it's put together, and it makes troubleshooting easier when you know what you're working on. And all things considered, an Axe is one of the cheapest helis to repair, so don't be afraid to fly it. Just take it slow, and don't get too upset when you do crash it.

I wish you could have seen the grin on my face the first time I got a solid hover- you'll know what I'm talking about when it happens for you!

Take care!

Ray

[mashburncs]

Ray K.

Thanks for the encouragement. I actually bought the Axe CP for my 8 year old son, but we are both training on the simulator, and will both be flying (and crashing) the chopper. He is actually better on the simulator than I am.

I am using RC Helicopter Simulator v1.9 from www.alphamacsoftware.com because that is the only helicopter simulator that will run natively on the MAC. Long story, short, but after using Windows for many years, UNIX, LINUX, and trying out MAC OS X, I fell in love with MAC OS X, and got rid of all of my PC stuff, and switched to MAC about 2 years ago. I have an old G4 MAC, so I cannot run Windows natively, that limits my simulator to RC Helicopter Simulator only. However, the simulator feels very real to me, it takes into account the helicopter weight, moments, and lift characteristics to model the motion, and it doesn't look bad either. I am trying to fly the Raptor helicopter, because it is most like the AXE CP, compared to the other helicopter choices currently available in the sim. It is still real enough for me to crash because I get going to fast, get disoriented, thus move the control sticks the wrong way, or get the chopper to far away from me to tell what its orientation is, and again move the sticks the wrong way, and drive it into the ground. The only drawback that I can really tell about the simulator, is that it doesn't let me simulate throwing the idle up switch instantly changing the throttle and pitch curves. But that limitation doesn't effect me at this moment, because I cannot fly in normal mode yet.

Thanks again for everything.

Curtis

[Iceman140]

Curtis-

I feel your pain with the sim thing. I, just yesterday in fact, finally got around to getting a sim. I'm running Reflex XTR, and as far as I can tell it VERY closely approximates what you can expect in real life. I was stunned at how "real" it is! I'm using about 15% exponential on the aileron and elevator controls, and that seems to be pretty close to the real McCoy.

You did right getting a sim first. I got the heli first, figuring that baptism by fire would be my best bet. I can tell you right now that I would have saved a few hundred dollars in repair costs by getting a sim at least at the same time I bought the heli. I think to this point, I've killed 8 sets of blades ($20 a set), 4 tail rotors ($6 each), a fuselage ($25), a tailboom ($15), countless blade grips ($4 a set), a flybar, 2 flybar carriers, 1 set of skids, and many other little parts.

On the other hand, though, there's nothing like flying the real heli. If you can hover on the sim, it's time to try it for real. There are other factors that go into flying the real thing that a sim can't.... simulate. Like sweaty palms, a sudden mechanical failure, a bug in your ear that won't go away, a sudden and powerful gust of wind... the list goes on. I don't regret flying my Axe one bit. Sure, I could have saved some money, but experience isn't free.

Don't be afraid to crash. It's going to happen whether you want it to or not- it's just part of being a heli pilot. As you become a better pilot, you'll crash less, and that's why sims are so valuable- it substantially reduces your repair bill. But there's also something to be said for actually working on your heli. You'll have a better understanding of how it's put together, and it makes troubleshooting easier when you know what you're working on. And all things considered, an Axe is one of the cheapest helis to repair, so don't be afraid to fly it. Just take it slow, and don't get too upset when you do crash it.

I wish you could have seen the grin on my face the first time I got a solid hover- you'll know what I'm talking about when it happens for you!

Take care!

Ray

Love all the Axe info you've given Ray. One thing the Sim gives you that real flying don't. A taste of more heli's. Some many heli's. So few excuses for "accidentally" ordering one. It's still easier to ask forgiveness than it is to ask permission.

Keep flying.
Ed

[Ray K.]

Okay, I crashed again last night.

But it wasn't my fault, I swear!

The reason that I'm putting this under this thread is because this last crash has inspired me to build Axe CP version 3.0.

What happened was this: I was doing some stall turns, and things were going pretty well. I may not have been getting *totally* vertical, but it was vertical enough to be called a stall turn. Anyway, I was on the forward approach to the maneuver, and I noticed that my tail was pretty twitchy on the way in. Thinking nothing of it, I went ahead with the maneuver, and was totally committed to it (read: the helicopter was nose up and vertical) when... MY FREAKING TAIL MOTOR DIED!

So my heli lost all yaw control 10 feet off the deck and went plummeting to it's death in an uncontrollable spin. And, of course, being in a total panic I didn't have the presence of mind to flip the throttle hold switch. So the heli hit the ground tail-first and with the throttle at about 70%. I mangled my tailboom, cracked my tail motor mount, and destroyed a blade and it's grip all on top of the dead tail motor, of course. Ironically, the tail rotor itself survived the ordeal intact... because it wasn't spinning! The crash would have been pretty funny if I wasn't so pissed about it. I hate mechanical failures.

So I'm going with a brushless tail motor. I was going to go direct drive also, but no one had parts in stock. So I'll be rockin' a Great Planes Ammo 12-30-3850 BL tail motor with a GP Silver Series 8A controller, hooked up to an 8T pinion driving the stock tail rotor assembly. I figure that the improved power in the tail will be better able to cope with the BL main motor, and BL motors last forever if you take care of them.

I say that this will be Axe CP v3.0 because I'm also going to be totally re-doing my fuselage. This means that my battery mount system will be different, and the way that I'm going to be mounting both of the ESCs is going to be different from what I did before- totally different.

As usual, I'll be doing a full writeup of the whole affair and I'll take some photos too. I expect that this will be the last version of my heli, so I'll be sure to make this an extra-good writeup.

Parts should arrive by Thursday....

-Ray

[mashburncs]

Ray,

Sorry to hear about your crash, but excited to see your new rebuild. As you know, I am a complete noob with RC helicopters, however, I have a good deal of experience with real aircraft design. If I were you, I think I would take this opportunity to get the c.g. exactly under the main rotor shaft if at all possible, and if not, I would prefer the c.g. to be slightly forward, as opposed to aft of the main rotor shaft. This position should give real good flying qualities both normal and inverted, with additional forward stability if the c.g. is slighty forward of the main shaft.

I have also read some cautions about using a brushless tail motor due to supposed reaction lag being greater than brushed motors. However, I would probably try it myself just to see if it really was that significant to make the heli more difficult to fly.

Keep us posted.

Curtis

[VBDave]

Why not stay brushed and use the direct drive method posted all over? Using a GWS? plane prop directly mounted to tail motor and motor mount inverted to face the other direction...

Wish I had the link. my bad..