I'm lost

[Sander_Picco]

Realy need help!

I just can't get more than 5 minutes airtime with my pic. I have the following setup:

- 3 cell LiIon
- G-310 main motor
- pinion 10 th.
- stock main gearwheel
- pro tail motor
- alu swash
- cut blades (V-cut)
- bearings on main shaft
- one-way clutch on main shaft
- piccoboard pro
- stock paddles

I have tried and checked a few things, but without result:

- gear meshing pinion-maingear wheel
- uncut blades
- stock main motor
- balanced the LiIon cells
- little pos. pitch on the paddles
- glue the pinion to the mainmotor shaft
- stock battery (NiCad 9,6 V 750MAh)

Are there any options I have mised? I'm thinking of building it back to stock to find out whats wrong.

Please help me!

Sander

[ofels]

</font><blockquote><font class="small">In Antwort auf:</font><hr />

- 3 cell LiIon
- G-310 main motor
- pinion 10 th.


[/ QUOTE ]

Here you go- the cut blades with a 10 pinion and the 310 engine do not fit well together.

The pinion leads to a higher rpm but also enforces a highr torque and thus way more power consumption from the main motor.
Additionally if your blades are cut too much, the higher rpm is needed for takeoff thus a constant high power drain is in effect.

Try the 9 pinion, the 410er motor or consider a brushless engine.
The 410er can handle the torque forces much better with less power consumption.

Oliver

[rdn1153]

Don't use the 410 with a standard PB if you're not using separates. You need the Pro PB to handle the current of a 410 or you'll just burn up the FET's.

[VJH]

Brother #1 is using the 310, 3 LiPo 1020mAh and the 8 tooth pinion and getting 20 minute flights.
How hot does you motor get with the 10 tooth pinion? I think it would be pretty close to damaging temps.

[Sander_Picco]

Thanks guy's for all your advises.

Here are the results:

I tried the G410 motor from my piccolo pro. I use the piccoboard pro, so the current can't be a problem. I got less then 5 minutes flight time. It looks to me the G-410 motor is to heavy for my pic-fun.

I got back to the G310 motor and installed a 8 tooth pinion. Its waiting for its first flight. I will keep you up to date!

Someone said to me it could be a loosen flybar link. Is there someone with the same experience.

New suggestions are always welcome.

Sander

[heloaddict]

ME TOO!

Sander_Picco,

Be sure and check your blade tracking. Poor tracking can easily rob lots of power. I'm running two cells with an 11 tooth pinion and stock main gear with the stock 310 motor and get 14 min out of GE with a 5 min break in the middle of the flight. I would think you should be able to run with an 8 or 9 tooth pinion and easily get 15 - 20 min. What is the mah rating of your battery pack? How much does your Pic weigh? Do you know how much current capacity you are putting back in per charge? Does your Pic have any vibration?

Just happened to notice that you mention a Pic Pro tail motor. Are you doing a DD tail? If the Prop is on backwards that can also cause excessive current draw.


Hope this helps.

Doug

[Sander_Picco]

The capacity of my LiIon is a 1200 MAh. Every time I charge them I put in about 800 MAh.

I dont know how to measure the traking. And I toally don't know how to correct it. Any suggestions are welcome!

Yes there are some vibrations in my fun pic. I havn't find out where its coming from.

I have no DD tail.

My pic weights about 290 gram including LiIon (!!)

Sander

Here's a link to Blade Tracking at Paul's website.

Here are a few more webpages about it:
Blade Tracking
Blade Tracking

If your putting 800mAh approx in after each charge and only getting 5 mins of flying then that equates to an average current draw of 9.6A, that is one hell of a lot. [img]/ubbthreads/images/graemlins/blush.gif[/img]
IMHO even poor gearing and motor combination could account for this.
Also can your liths deliver that kid of current happily? [img]/ubbthreads/images/graemlins/confused.gif[/img]

On my 2 cell set up by heli only pulls about 2.8-3.0A at 8.4v. With 3 cells you should pull less that that.
[img]/ubbthreads/images/graemlins/shocked.gif[/img]