For anyone thats interested I installed the HS65hb servos and they are the smoothest I've ever had on there. Not a bad price either at 21$ something a piece.

Originally Posted by Kevin Greene

My motor is a rather low 2750kv motor that was given to me by a buddy that crashed his Dynam 450...On 3S with this motor on this EXI heli the head speed is rather on the low side...Just now, for grins, I installed a 4S 2200mAh battery and tried it out...It seems that head speed is where it's at, BABY!!!...The heli responded well and JUMPED in hover when I blipped the throttle....The motor was cool to the touch (I'm REALLY surprised how cool this motor is running---NO HEAT AT ALL!!!) and the ESC was so cool that when I did the "kiss" method (touching the ESC with my lips???!!!) the ESC was also barely warm...My old battery pack didn't fare as well as it was puffed just like it did the last time I flew it in an EDF...Looks like I need to get a new set of 4S 2200mAh batts!!!

I use 4s batteries in my 450s (all except 1). for the regular ones I use 1800ma 4S. About 3/4 of an inch forward on the tray. Are you balanced with the 2200 4s? On my stretched 450 I use 2200 and even then it's juuuust slightly nose heavy.

On my 4s 450s I use 2900 and 3000kv motors. So for 2750 I'm sure you're fine with a 12t or 13t pinion. If you start going inverted maybe a 14t. I have 1 more 450 I was thinking of flying on 4S but it has a 2700kv motor and I have a 14t for it.

I say totally up to you whether you think you're ready. If you only have -2 pitch make sure it's not too windy. Or make your pitch curve has a little more negative at the bottom. 40,50, 100 or 30, 50, 100. Idle1 or 2 is great but might be twitchy for someone just learning ff.

What servos is everyone using on their Exi 450s? I'm currently using Exi 213f digital servos all around, but they use alot of juice. My lipo, esc and Castle BEC always are warm after a 4 minute flight. Does anyone see an issue with using 4 digital servos for cyclic and tail? My lipo I think takes a beating, its a Blue Lipo 3s 2200mah 30c, after less than 30 flights, keeping flights to 4 minutes its slightly puffed. Btw my Exi 450 is FBL. Im wondering the best option, buy 3 non-digital servos for the cyclic or buy a lipo with a higher C rating? Thanks.

What is up with brand new servos going out in mid flight with no warning?
Forget my recommendation of the HS65hb servo. I contacted Hitec and it could be 7 to 10 days after they get the servo back before they'll send another out. Not to mention a total rebuild including frame for the heli, which of course I'll have to eat the cost on.
I just got it back in the air.
Do all servos just go out? I mean $21 wasn't that expensive, but it wasn't that cheap either.
The electronics went.
SHEESH!
O.K. I'm done ranting now.

Originally Posted by r/c basher

What servos is everyone using on their Exi 450s? I'm currently using Exi 213f digital servos all around, but they use alot of juice. My lipo, esc and Castle BEC always are warm after a 4 minute flight. Does anyone see an issue with using 4 digital servos for cyclic and tail? My lipo I think takes a beating, its a Blue Lipo 3s 2200mah 30c, after less than 30 flights, keeping flights to 4 minutes its slightly puffed. Btw my Exi 450 is FBL. Im wondering the best option, buy 3 non-digital servos for the cyclic or buy a lipo with a higher C rating? Thanks.

While digital servos can draw more current than analog for sure, your lipo is far more taxed by your motor. Your servos tax the BEC. A higher rated lipo will certainly come down cooler but it won't really change the work the BEC has to do. I run digital servos and don't worry about it.

Digital servos can develop full torque with even the smallest error. Analog servos will develop full torque only after a few degrees of error in the position. Digital flies better on both cyclic and tail. FOr cyclic, it makes hovering smoother and for the tail, tighter as well. As said, it's taxing the BEC more than anything. Warm for BEC and ESC and battery is ok. What is not ok is HOT. I like to define hot as too hot to touch and hold. That's about 140F for most people. If the battery puffs but is not too hot to hold onto, yu may be dragging it too far down. Check your cell voltages at the end of the flight and if sitting there and it's below 3.7V per cell, I"d advise taking shorter flights.

I have only one 450 EXI with analog servos and it's the one with my flymentor on it that I use for heli training others. If you have all digitals and an exernal 3A switching BEC, you should be fine.
which servo went out ? cyclic?

Thanks guys, the motor, battery, BEC, and esc come down only warm so I should be good. The lipo does puff up some after a flight but goes away after a while. This is after a 4 minute flight. I checked the voltage after the flight and if I remember right it was around 11.8 volts or roughly 3.9 volts per cell. My battery is a Blue lipo 3s 30c 2200mah, its not very old either, I'm guessing less than 30 flights in the past 6 months. I'm also using an 11 tooth pinion, I was using a 13 tooth but step down to the 11 to put less strain on the electronics and battery.

Heres my setup-
Motor- Exceed rc Alpha 400 3500kv
Esc- Exceed rc 30 amp
BEC- Castle Creations 10 amp
Servos- Digital D213f
Gyro- Tarot 3 axis FBL system
Receiver- Ar6200
Batt- Blue Lipo 2200mah 3s 30c
Tarot Head
Btw this is the older V2 Exi not the pro. I know my Esc is on the small side but it was what I had on hand when I built my Exi 450, with the External BEC shouldn't I be ok though?

Originally Posted by rocketscience

I use 4s batteries in my 450s (all except 1). for the regular ones I use 1800ma 4S. About 3/4 of an inch forward on the tray. Are you balanced with the 2200 4s? On my stretched 450 I use 2200 and even then it's juuuust slightly nose heavy.

On my 4s 450s I use 2900 and 3000kv motors. So for 2750 I'm sure you're fine with a 12t or 13t pinion. If you start going inverted maybe a 14t. I have 1 more 450 I was thinking of flying on 4S but it has a 2700kv motor and I have a 14t for it.

I say totally up to you whether you think you're ready. If you only have -2 pitch make sure it's not too windy. Or make your pitch curve has a little more negative at the bottom. 40,50, 100 or 30, 50, 100. Idle1 or 2 is great but might be twitchy for someone just learning ff.

My heli isn't nose heavy with my 4S batts...

I'm now waiting on parts---I did something REALLY stupid the other evening...I decided to program in the throttle and pitch curves for Stunt 1 and Stunt 2...I got through the throttle curve programming and realized I made a mistake as I was really in the pitch curve programming...I went all through the throttle curve programming and took a break...I forgot that I needed to go back through the pitch curve programming..I took the heli outside (It's about 11:00PM) and ran the heli up and hovered for a few seconds....I set the heli down but kept the rotor speed up so there would be only a slight transition adjustment needed going from position 0 to Stunt 1...The heli was at 1/2 throttle stick and just about to get light on the skids...I hit the Stunt 1 switch and the heli SHOT STRAIGHT UP and OUT OF SIGHT!!!...Literally in the blink of an eye!!!...I could barely see the glow from the LED on the RX...I hit the switch to go back to position 0 and could tell the heli was falling...I tried to time it so that I could go to high throttle to arrest the descent...I was late and SMACK!!!...

Scratch a set of blades, feathering shaft, one blade grip, one lower CF fuselage sside, main gear, flybar, landing skid, and base plate..It could have been MUCH worse!!!...The tail boom wasn't even bent---Can't figure that one out...I think tht I did manage to soften the landing a little...

Kevin

Originally Posted by Kevin Greene

My heli isn't nose heavy with my 4S batts...

I'm now waiting on parts---I did something REALLY stupid the other evening...I decided to program in the throttle and pitch curves for Stunt 1 and Stunt 2...I got through the throttle curve programming and realized I made a mistake as I was really in the pitch curve programming...I went all through the throttle curve programming and took a break...I forgot that I needed to go back through the pitch curve programming..I took the heli outside (It's about 11:00PM) and ran the heli up and hovered for a few seconds....I set the heli down but kept the rotor speed up so there would be only a slight transition adjustment needed going from position 0 to Stunt 1...The heli was at 1/2 throttle stick and just about to get light on the skids...I hit the Stunt 1 switch and the heli SHOT STRAIGHT UP and OUT OF SIGHT!!!...Literally in the blink of an eye!!!...I could barely see the glow from the LED on the RX...I hit the switch to go back to position 0 and could tell the heli was falling...I tried to time it so that I could go to high throttle to arrest the descent...I was late and SMACK!!!...

Scratch a set of blades, feathering shaft, one blade grip, one lower CF fuselage sside, main gear, flybar, landing skid, and base plate..It could have been MUCH worse!!!...The tail boom wasn't even bent---Can't figure that one out...I think tht I did manage to soften the landing a little...

Kevin

Ouch!

Originally Posted by biker dude

Ouch!

I bought a BOATLOAD of NIB/used parts CHEAP from a guy here on RCG...Almost 100% Align parts...So many genuine/new Align parts that I'm going to rebuild my heli using these parts primarily......I won't be able to post in this thread any more due to having a 90% Align heli......Also included was a NIB 4000kv motor---Good by needing the power of 4S as I have many 3S batts..

Kevin

We've finally had some decent weather so I've been able to get the EXI 450 out a few times.
Yesterday, first battery, I was in the air for about 30 seconds to a minute - just hovering and making sure everything looked right. For no reason at all she shot straight up, then did a 360, banked right and started to go down. I fought with it for what seemed like half an hour (my brother say 30 or 40 seconds), I could almost gain control, then it just did it's own thing again. It ended in a crash - broke one blade, bent the flybar, and broke a few plastic pieces on the head (finally get to use that metal head I've had for a while).
I don't find anything loose, control rods were still all in place - I don't see any physical problem problems that look like a cause. Any idea of what might happened?
I'm about 3 miles from McChord AFB - any chance they have caused interference?

Originally Posted by karlik

We've finally had some decent weather so I've been able to get the EXI 450 out a few times.
Yesterday, first battery, I was in the air for about 30 seconds to a minute - just hovering and making sure everything looked right. For no reason at all she shot straight up, then did a 360, banked right and started to go down. I fought with it for what seemed like half an hour (my brother say 30 or 40 seconds), I could almost gain control, then it just did it's own thing again. It ended in a crash - broke one blade, bent the flybar, and broke a few plastic pieces on the head (finally get to use that metal head I've had for a while).
I don't find anything loose, control rods were still all in place - I don't see any physical problem problems that look like a cause. Any idea of what might happened?
I'm about 3 miles from McChord AFB - any chance they have caused interference?

what rx and tx you used. what is esc and any external bec used?

Originally Posted by karlik

We've finally had some decent weather so I've been able to get the EXI 450 out a few times.
Yesterday, first battery, I was in the air for about 30 seconds to a minute - just hovering and making sure everything looked right. For no reason at all she shot straight up, then did a 360, banked right and started to go down. I fought with it for what seemed like half an hour (my brother say 30 or 40 seconds), I could almost gain control, then it just did it's own thing again. It ended in a crash - broke one blade, bent the flybar, and broke a few plastic pieces on the head (finally get to use that metal head I've had for a while).
I don't find anything loose, control rods were still all in place - I don't see any physical problem problems that look like a cause. Any idea of what might happened?
I'm about 3 miles from McChord AFB - any chance they have caused interference?

2.4 gHz or 72 mHz???...There's always a chance but I doubt it...Due to your close proximity to the heli your signal should have been strong...I've seen reports with guys experimenting on 72 mHz to see if one radio could affect another and the results were that the radios had to be pretty close to one another to affect the host radio...Closer than you would expect...

Spektrum 2.4 radios choose two open frequencies and if one is affected it switches to the other...Futaba 2.4 uses frequency hopping...

Have you done a range test???...If using 72mHz the crystal could have been vibrating in the RX...TX could be putting out variable power...

Batteries fully charged in the TX???...RX getting full voltage and not browning out???

I would start with a range test---If OK then I would do another range test with the heli bolted down and run through several power settings with the antenna down (72 mHz) or in range test mode (2.4 gHz)...If flying 2.4 gHz I would re-bind the TX to the RX...What RX are you using???...I have over 20 Orange Rx's and have never had a problem with any of them but yours could have an intermittent problem...

Low voltage to the RX could be an issue...Do you have a voltage logger???

Start troubleshooting with these suggestions and let us know what you find...

Kevin

2.4 - I haven't used my 72 stuff for years.
Range test is fine. After repairs and while the motor was unplugged I tried to re-create and everything was fine.
Using a 2801 - after the crash I used the same xmitter on my ufly for about an hour.
I was flying in a little secluded park all alone - any other rc stuff would have been miles away (there's only enough room here to practice orientation and not much more).

Originally Posted by karlik

2.4 - I haven't used my 72 stuff for years.
Range test is fine. After repairs and while the motor was unplugged I tried to re-create and everything was fine.
Using a 2801 - after the crash I used the same xmitter on my ufly for about an hour.
I was flying in a little secluded park all alone - any other rc stuff would have been miles away (there's only enough room here to practice orientation and not much more).

same question I asked before. what is your esc and if it /w built-in bec. or you external bec. what are cylic servos and tail servo. motor.....

most low amp esc /w built-in bec is linear type and heated up easily. Some built-in bec may not even provide enough current for all servos under peak load, cause voltage drop and rx brownout. your 450 is fbl? some pilot reported fbl unit like 3gx re-initialize by itself for unknown reason and cause crash.......

can you post more info on your heli hardware so that we may look at..