Comments

• 

  John September 23, 2014 at 2:09pm

  Gustav, 
  
  It looks great what you did for the gopro.

  You were saying :"" Your OS motor looks to be the closest that I would use, with the two 3S packs in series.""
  
  If it will be in series, then it will be a 6S, isn't it? or you meant in parallel? 
  If it will be 6S, will the motor handle a 6S, because on the description, they are saying 4S?
  
  What flight duration will we get in this configuration? If my total weight will be 4Kg.

  What difference will make if we use a bungee for the take off? will we change the prop then?
• 

  Gustav Kuhn September 23, 2014 at 1:24pm

  My Talon now has a different perspective on the world...

  
• 

  Gustav Kuhn September 23, 2014 at 1:15pm

  Elios,

  Work from 100 Watts per pound of total weight.

  Also, you would want a top speed of say 90 Km/h, for safety.

  You can go up to 12" prop, if you don't use folding props.

  Now calculate for a given pitch of say 6" to 8" you would need what RPM to give you 90 Km/h.

  Also, the Talon is hand launch, you do not have the luxury of a long runway to get to flying speed, so you need enough power and rpm to basically get Talon from 0 to 25 or so Km/h in less than about 5 meters!

  Depending on how hard you can throw!

  In my opinion, if you had to relate to a glow motor,you would need at least a '36 to '40 size.

  My next Talon is getting this motor

  http://www.hobbyking.com/hobbyking/store/__18233__turnigy_d3548_4_1...

  Yes, a bit of overkill.

  Your OS motor looks to be the closest that I would use, with the two 3S packs in series.

  The ESC is a bit of overkill, I doubt if you will draw more than 60A, use a 12X6 prop.

  Do the first few flights without any extra electronic stuff.

  Dave is getting fantastic flights with his setup, I think I'm not too far behind him.

  Both our setups are posted here somewhere..........
• 

  John September 23, 2014 at 11:55am

  Well, I just received the talon now with the extension wing. I am so excited to go and try it in the weekend. 

  I need some help to select the best combination: 

  I have a payload of 750g as cameras, vTX, antennas, APM, telemetry... without counting the batteries. 
  
  I will start to order the motors, prop, and batteries... What is the best combination to get the longest flight duration with the payload of 750g ? 
  
  I will list what I have now with me, if they dont work, tell me which motors and props to buy: 
  
  I have for the moment with me the Pheonix edge 100A ESC and those motors and those batteries: 
  
   Batteries: 2 x 3S 9000 mAh and 1 x 4S 5000 mAh batteries
  
  And motors: 
  
  Motor 1: OSMG9530  http://www.osengines.com/motors/motors/motor-specifications.pdf
  OMA-3825-750 (.30 Size)
  Rotor Diameter (mm): 38
  Magnet Length (mm): 25
  kV: 750
  Watts: 590
  Weight (oz/g): 6.7 (190)
  
  
  Motor 2: Jamara E-Motor Magnum A2820/6

  http://www.conrad.at/ce/de/product/428816/Jamara-E-Motor-Magnum-A28...

  Specifications  Revolutions / v : 1000 
  Internal resistance : 59mOhm 
  Idle current: 2.0A 
  Max A: 37A / 60S 
  Shaft Diameter : 4.00mm 
  Output: 550-Watts 
  NiMH Battery : 8 ~ 14 
  LiPo Battery : 3 ~ 5 
  Propeller NiMH: 11x8 Propeller LiPo : 3xLiPo 11x6 / 10x7 4xLiPo
  Application: 1000-2500g
  
  
  Motor 3: Emax BL2826/06: http://www.toysonics.com/emax-bl2826-06-950rpm-v-outrunner-brushles...

  Features

  • New Emax BL2826/06 950Rpm/V Outrunner Brushless Motor

  • Model: BL2826/06

  • No. Of cells: 3-4 Li-Poly

  • RPM/V: 950

  • Max. efficiency: 86%

  • Max. efficiency current: 20- 30 A (>78%)

  • No load current / 10V: 2.1 A

  • Current capacity 61 A/60s

  • Dimensions: 30x26 mm

  • Shaft diameter: 5 mm

  • Weight: 182 g/6.41 oz

  • Recommended model weight: 2-3.2 kg

  • Recommended prop without gearbox: 13*8; 12*8

  Regards
  Elios
• 

  Gustav Kuhn September 22, 2014 at 11:12pm

  The argument for going to high cell count rests on the fact that at higher voltage you can get the same power/Watts at a reduced current, so less power is wasted as heat in the motor, wiring, esc and battery.

  However, if you double the cell count, you will need to halve the capacity, since a 6S 2000 mAh pack will , roughly, weigh the same as a 3S 4000 mAh pack, and again, roughly, take up the same space.

  My setup just "fell" together, I had a motor from another plane, electronics that can't run higher than 3S, and batteries that also run my Quad.

  And at 7Amps, well, not to much heat generated there.

  But I agree, not the optimum setup.

  @ Gustav, 

  In your configuration setup, you are consuming around 7 Amps using a 3S battery, but if you were using a 6S, your consumption will be the half. 

  Does it mean you will have longer flight with 6S?
• 

  John September 22, 2014 at 6:57pm

  what is your flight duration and flying weight?
• Adrian September 22, 2014 at 6:44pm

  Hi,

  This is the setup that I am going with..

  http://diydrones.com/group/x-uav-talon/forum/topics/xuav-talon-mult...

  I decided to go with a high cell count (6S) to reduce the current and a lower Kv motor.. this reduces the overall current load.

  As dispated power (loss) is related to the square of the current (P = I^2 * R) this will reduce the lost power due to heat dramatically. Halve the current, power loss (esc & battery heating) is a quartered.

  down side.. need more cells..

  Adrian
• 

  John September 22, 2014 at 4:52pm

  Scott, 
  What about the ground clearance with the standard tail, I feel the prop will touch the ground every time it lands. isn't it?
• 

  John September 22, 2014 at 4:21pm

  Thanks Scott, 
  
  I am there on page 8 of 108 :). I still have a long way to finish them. 
  
  Were you able to find a gimbal with pantilt to put it inside the doom? 
• Scott Pritchett September 22, 2014 at 4:12pm

  Right is use 4S. I really recommend you go look at the thread on Rcgroups.  All of my config info is over there.  I use the Cobra 3520/12 820KV motor on 4S, YEP 80A ESC set to 12 degrees timing, fast start, hard brake and freewheeling on. I use a 13x8 APC E prop or an aeroCAM folder of similar size.

  Min, Max and Cruise airspeeds are set to: 13, 22 and 18 meters per second.

  If you use 6S, you'll want a proportionately lower KV motor.