My 700E DFC PRO HV Build

[HarveyR]

Hi, First good surprise during the build is that the factory assembled main grips were real easy to get appart, the bearings and thrusts just came out with a slight push, allowing me to check the grease and washer order (in fact all was fine)!

I remember that I never managed to do it in my 700E DFC HV build, despite messing around with the oven, freezer, vice, hammer, ...

So, it's on a good start for now. No questions yet.

[JohnTC02]

Never had any issues building my 700 pro or any of my Align birds.

Good luck with the build, your going to love it.

Post any questions then I'm sure someone here will help you out, I'll do my best to help but there are many on here that have more experience than I do.

Enjoy the build.

[Excalibur3]

Originally Posted by JohnTC02

Never had any issues building my 700 pro or any of my Align birds.

Good luck with the build, your going to love it.

Post any questions then I'm sure someone here will help you out, I'll do my best to help but there are many on here that have more experience than I do.

Enjoy the build.

+1 easiest build to date for me as well. Such a pleasure to build.


TS3D#1
NanoCPXBL,TREX550PRODFC,
TREX700PRODFCHV, DX8

[HarveyR]

Thanks for the feedback!

I like to have loads of room to get the ESC to Motor wiring done fine, so I do it early:





PS : How can I insert the pic straight in the post?

[Excalibur3]

You need to use tap a talk if your on a smart phone or sign up for photo bucket.


TS3D#1
NanoCPXBL,TREX550PRODFC,
TREX700PRODFCHV, DX8

[HarveyR]

Hi, not many questions to ask, the build is going smoothly. It's quite impressive the quality of the kit and just how nicely everything lines up for the screws just to fall in without any hassle.

Only thing I pester against is why Align preassemble some parts with threadlock and some without (but with tight screws, so you can't know)... either they should always do it or never, because it's a pain undoing all screws on the main gear assembly just to see all was fine and threadlocked/greased... while the tail hub was tight but not threadlocked.

I'm currently rooting the wires, then I'll be fine setting the link rods and servo arms etc. and getting into the electronic setup (3GX, subtrims, ...).

Maybe first test flight will be for the WE!

[JohnTC02]

For some reason Align likes to keep you guessing when it comes to which screws have threadlock and which don't.

When building new kits it's good practice to remove every screw clean them then replace with threadlock, you will then have peace of mind knowing all screws are fitted correctly plus if they do come loose you can only blame yourself.

It's happened to me when the ball link on the tail came out mid flight, nice forced landing while piroing at a high rate of knots.

If you have any tight bolts then a little heat will help with removing them.

Good luck.

[HarveyR]

Finalising the 3GX setup and I want de finalise servo horn fitting. Should we put threadlock on the servo horn screw? I'm just about sure I've read from time to time that you shouldn't put thread lock on the servo horn screw... but as it's all metal I don't see why not?

What to do....

[JohnTC02]

Personally I always use threadlock when fitting the servo horns, if they come loose in flight then it's game over.

I don't see any reason not to use it, as you say it's a metal thread.

[atkin]

Some servos are prone to threadlock getting into gears. Use "just enough" is my thinking


Sent from my iPad using Tapatalk

[HarveyR]

Well, my build now hits to an end (with threadlock on the servo screws). The heli is all built and setup ready for first flight hopefully this WE!

Still a few things to check. I set my Gryphon BEC to7.7 Volts (I put the 7.4V switch on "on", all others on "off", and then put the potentiometer to maximum, this gives 7.7V as specified in the documentation). I could also have set it to 8.4V (all switches on "off"). But I thought 8.4 is a little risky (maximum allowed value by the HV system, so any surge might exceed)? What are others doing (same goes for Hercules Super BEC, I always use 7.4 and not 8.4).

Last, here are my CC settings, anyone see anything wrong? In particular:

PWM Rate: Outrunner Mode --> I have this on my NoPro DFC, but remember there was debate about what to put (although it is obviously an outrunner)

Governor Gain: Low (15) (*) --> I have "custom 8" on my NoPro DFC because there was discussions about stripping at the time with higher gains. I guess this is history now with teh black gears and that the default 15 is OK?

Auto-Lipo Volts/Cell: 3.2 Volts/Cell (*) --> for some reason I have 3.0 on my NoPro DFC



################################################## #####
# Castle Link Data File
# Created: Friday, April 11, 2014
# Do Not Edit This File By Hand
################################################## #####
Hex55: 85
Brake Delay: .6 sec (Delayed) (*)
Brake Ramp: Immediate (*)
Motor Start Power: Medium (59) (*)
Direction: Forward (*)
Brake Strength: 0%, Disabled (*)
Power-On Beep: Enabled (*)
Motor Timing: Normal (5) (*)
Data Log Enabled: 511
Current Limiting: Insensitive (210A)
Vehicle Type: Helicopter
Throttle Type: Governor Mode
Throttle Response: Medium (5) (*)
Governor Gain: Low (15) (*)
Initial Spool-Up Rate: Medium (5) (*)
Head Speed Change Rate: Medium (5) (*)
Auto Rotate Enabled: False
Governor Mode Type: Fixed
Vehicle Setup - Battery Type: LiPo
Vehicle Setup - Number of Cells: 12
Vehicle Setup - Battery Voltage: 44.4000
Vehicle Setup - Gear Ratio: 9.333
Vehicle Setup - Motor Kv: 520
Vehicle Setup - Motor Number of Poles: 10
Desired Head Speed 1: 1800
Desired Head Speed 2: 1902
Desired Head Speed 3: 2006
PWM Rate: Outrunner Mode
Sample Frequency: 1 Sample / Sec (*)
Cutoff Voltage: Auto Li-Po (*)
Auto-Lipo Volts/Cell: 3.2 Volts/Cell (*)
Voltage Cutoff Type: Soft Cutoff (*)
Current Cutoff Type: Soft Cutoff (*)
Link Live Enable: Disabled (*)
Auxiliary Wire Mode: Disabled (*)
Automatic Data Reset: Always (0%)


Thanks to all!

[HarveyR]

So, got it spinning in the garden today (with no blades) to test and setup the ESC and stuff... Always a nice moment doing the final bench tests in the garden under the sun.

Everything seems perfect, it spins real smooth and quiet at 1900 RPM (which is what I plan to do the first flight at, as I used to fly my 690 at 1950, I figure the blades been a little bigger, I should spin a little slower)...

I spent quite some time setting the pitches and stuff up to get it all real perfect and symetrical.

First test flight will likely be tomorrow!

[bradi]

Originally Posted by HarveyR

Finalising the 3GX setup and I want de finalise servo horn fitting. Should we put threadlock on the servo horn screw? I'm just about sure I've read from time to time that you shouldn't put thread lock on the servo horn screw... but as it's all metal I don't see why not?

What to do....

Two weeks ago while hovering at 5 ft I had servo horn screw back out on my new dfc pro. It rolled over onto its side causing $180 in damage. I was positive I put thread lock on but didnt notice any on the screw during post crash inspection. I might have forgot to clean the servo horn screw before putting thread lock on...dono.

[HarveyR]

Sorry to hear about your heli.... I've put the thread lock on and I'll be checking the screws tomorrow after quite a bit of "dry spinning" today (ie spinnng without the blades).

I wonder if it could be good practice to dry spin for a LiPo or two (ie no blades), in essence I was initally doing this to check the RX / ESC settings (fail safe, TH, idle, SetRPM, ...) but I extended the tests a little thinking it was after all a good occasion to leave it "run in" and check the thing after just to make sure nothing is going loose. Of course it"s never the same as the real flight, but it does shake it in quite a bit (messing with the controls at 2000 RPM).... However, be careful to do it by short periods because it heats a little as no blades means no wind.

[HarveyR]

Well that's it, first two flights done and all is fine, it's incredibly quiet and smooth, really nice, and the new canopy and fancy skids (I too the 800E PRO skids just for fun) make it look different than the 700E DFC.

Only thing I don't understand is why on my 700E DFC HV I have 35% AVC Gyro gain (futaba CG10) and on the 700E PRO HV I have 55%... They both work just fine with their respective settings, but they are very different. The PRO was no good at 35%, it was doing slow wags, so not enough gain, while the DFC was doing fast wags at 55%, so too much gain. Anyone know if there could be a reason for these quite different Gyro gain settings?

[ddj74]

Different servos and different motor.

[rcflyerheli]

Originally Posted by bradi

Two weeks ago while hovering at 5 ft I had servo horn screw back out on my new dfc pro. It rolled over onto its side causing $180 in damage. I was positive I put thread lock on but didnt notice any on the screw during post crash inspection. I might have forgot to clean the servo horn screw before putting thread lock on...dono.

I don't use threadlock, and I made a significant change as soon as I started running the metal gear full size servos. I ordered a pack of 3mm x 6mm socket head screws and 3mm star lockwashers.

I hate those phillips head screws. Just a royal pain to use compared to the socket head screws. The star washers provide a good lock on the screw head and I haven't had one get loose in 3 years.

[HarveyR]

Originally Posted by ddj74

Different servos and different motor.

The servos are the same... the motor is indeed different, so are the blades (700mm instead of 690mm)

Can anyone else confirm that they have noticed significant différences in gain adjustment between the 700E DFC HV (35%) and the 700E PRO DFC HV (55%, and maybe higher, I'll be readjusting on next flight)?

[HarveyR]

I'm looking at the CC logs and all seems fine... Ripple has a peak at 2.49 and averages 1.66, does that seem safe?

[HarveyR]

About the ripple, got my answers here:

https://www.helifreak.com/showthread...39#post4903139 -->
CC's statement (when they use to post here) was that ripple should be under 10% of the average pack voltage. 5% is even better.

I'm guessing you have a 12s or ~50V, so 10% would be 5V, and 5% would be 2.5V. Sounds like you are in good shape.

and here http://www.rcgroups.com/forums/showthread.php?t=1101016 --> Ripple voltage is a measure of the DIFFERENCE between the voltage of the battery during the "off" PWM time, and the "on" PWM time (the difference between the battery voltage when the motor is on vrs the battery voltage when the motor is off... when running at less than full throttle.)

There really isn't a "right" and "wrong" (or "bad" and "good") but it gives the user a method to determine how well different batteries are working in an application. For example, if you see 6V average ripple voltage with one battery, and 4V ripple voltage with another, it's a good bet the battery with the 4V ripple is handling the currents required by the motor much more effectively than the battery with a 6V ripple.

As the ripple voltage goes up, the input capacitors have to work harder -- and consequently get hotter. So the rule of thumb is the lower the ripple voltage, the better the battery and wiring.