RSS Facebook

RCMF

*

RCMF Donations

Enjoy using RCMF? How about a wee donation to help us keep you in the style to which you've become accustomed?

Welcome, Guest. Please login or register.
December 12, 2018, 06:04:10 AM

Login with username, password and session length

Articles

Author Topic: Electric Autogyro project  (Read 1803 times)

0 Members and 1 Guest are viewing this topic.

Offline paulinfrance

  • Trade Count: (0)
  • RCMF Ace
  • ******
  • Thank You
  • -Given: 0
  • -Receive: 25
  • Posts: 1,937
  • Liked: 281
  • Country: fr
  • I'm so new it hurts!
Re: Electric Autogyro project
« Reply #40 on: November 21, 2018, 16:57:46 PM »
I have just published a 1 minute video ( so not to bore you ) of how I think the teeter head works,,,  :uk:


https://youtu.be/8VqmccIbvcg
Mode 2 THE only way to fly


Offline paulinfrance

  • Trade Count: (0)
  • RCMF Ace
  • ******
  • Thank You
  • -Given: 0
  • -Receive: 25
  • Posts: 1,937
  • Liked: 281
  • Country: fr
  • I'm so new it hurts!
Re: Electric Autogyro project
« Reply #41 on: November 23, 2018, 09:34:41 AM »
Rain and No wind is making me a bit desperate,,  :embarassed: running up and down the runway zigzagging like an idiot  :-\ so in desperation I added some scrap balsa to increase the tail surface  :embarassed: it has been covered since with red film,,
Mode 2 THE only way to fly

Offline Bigtradioman

  • Trade Count: (0)
  • RCMF Flight Lieutenant
  • **
  • Thank You
  • -Given: 1
  • -Receive: 4
  • Posts: 17
  • Liked: 2
  • Country: gb
Re: Electric Autogyro project
« Reply #42 on: December 02, 2018, 10:33:34 AM »
I have just come across this build thread and would like offer some guidance gained from 4 years of building and flying gyros which I started with building the Rich Harris RPG. Your design is similar to the Cranefly. Watching the hops video I would suggest the following mods. Increase motor downthrust. Suspend the model from the rotor spindle and Look for a hang angle of between 15 and 18 degrees. Trim in left rotor roll of around 5 degrees for the first hops. Our most successful rotor profile is the ClarkeY modified by drawing a line from leading edge to trailing edge to give a flat bottom and SHARP leading and trailing edge. Assuming both blades weigh the same, we balance for a cg lengthways that is on the centre of lift of the blade profile. This is usually around the thickest part of the profile. This is key to give the blades equal  lead and lag, you will understand the importance of this. Also with 2 blade designs you need far less pitch and roll movement to prevent over control which will stop the blades. Another requirement of 2 blade set ups is to increase the tip weight of the blade to reduce coneing and increase the gyroscopic effect of the rotor. This often means the blades struggle to get up to speed, hence the need for pre rotators. Lastly if a model goes nose vertical on lift off it is nearly always because of too much lift, rolling left is always due to insufficient lift. Hope this helps.


Sent from my iPad using Tapatalk


Offline paulinfrance

  • Trade Count: (0)
  • RCMF Ace
  • ******
  • Thank You
  • -Given: 0
  • -Receive: 25
  • Posts: 1,937
  • Liked: 281
  • Country: fr
  • I'm so new it hurts!
Re: Electric Autogyro project
« Reply #43 on: December 02, 2018, 12:12:47 PM »
Thanks for your well needed input, :af
               I haven't tried blades with a pointed leading edge or weighted, maybe the next step, I have put a pair of my older gyro blades on it which have a lot longer cord and have flown on a lot of my autogyros, but waiting for some decent weather, also I might order a helicopter gear wheel for spinning the head up.
  I did put a bit of right trim on the head and it does take off nice and straight, my last flight it did go well for around 50 metres, mainly due to reducing the amount head roll by 50% and increased engine down thrust, but probably overpowered as when I tried to gain height with full power it went skywards 'again' and rolled over into the ground.
Mode 2 THE only way to fly

Offline Bigtradioman

  • Trade Count: (0)
  • RCMF Flight Lieutenant
  • **
  • Thank You
  • -Given: 1
  • -Receive: 4
  • Posts: 17
  • Liked: 2
  • Country: gb
Electric Autogyro project
« Reply #44 on: December 03, 2018, 08:11:25 AM »
What are the dimensions of your blades? To give you an idea on a whippet or whippet derivation we are using a 3 blade set with modified clarke y, 60 mm wide x 6 mm deep x 40cm long with no shim. We are in the process of developing a 3 d printed sectional blade.
On my biggest gyro, a DAG 60, with a weight of 14lbs I use the same section blade, 70mm wide, 10mm thick, 1 meter long. No shim. https://youtu.be/hdCaa-UGBSE

Another video by a mate Rich Harris the designer of the RPG et al testing a teeter head https://youtu.be/fxPxKqnJIUk


Sent from my iPad using Tapatalk
« Last Edit: December 03, 2018, 08:17:25 AM by Bigtradioman »


Offline Bigtradioman

  • Trade Count: (0)
  • RCMF Flight Lieutenant
  • **
  • Thank You
  • -Given: 1
  • -Receive: 4
  • Posts: 17
  • Liked: 2
  • Country: gb
Re: Electric Autogyro project
« Reply #45 on: December 03, 2018, 08:16:45 AM »
This is thread by a mate, Steve Jones in the U.K. Gyronuts on 2 blade set ups. I have to confess that personally I have never been too successful with a 2 blade gyro conversion but many have. https://www.rcgroups.com/forums/showthread.php?2640846-Atom-Autogyro-Blade-setup


Sent from my iPad using Tapatalk

Offline paulinfrance

  • Trade Count: (0)
  • RCMF Ace
  • ******
  • Thank You
  • -Given: 0
  • -Receive: 25
  • Posts: 1,937
  • Liked: 281
  • Country: fr
  • I'm so new it hurts!
Re: Electric Autogyro project
« Reply #46 on: December 03, 2018, 11:30:56 AM »
Thanks,
    I will have a look when it rains,,, my home made 2 bladed heads have always worked may I say 'well', but my 3 bladed ones have always been a headache.
Mode 2 THE only way to fly

Offline paulinfrance

  • Trade Count: (0)
  • RCMF Ace
  • ******
  • Thank You
  • -Given: 0
  • -Receive: 25
  • Posts: 1,937
  • Liked: 281
  • Country: fr
  • I'm so new it hurts!
Re: Electric Autogyro project
« Reply #47 on: December 07, 2018, 08:38:57 AM »
The rain has stopped and a cross Wind at the model club, perfect for a flight, well it wasn't to be  :-\
the blades that were on my last gyro were cut down to fit and spun up well in the first few metres but that was it  :embarassed: it went from a fairground death ride to what Mr Dyson would have been proud to call his lawnmower,,  ::) the wider blades wouldn't give any lift, probably because they were too large and heavy, and not spinning up, one of the large blades weighs in at 85 grams and the thinner ones at 48 grams each.
Mode 2 THE only way to fly


 

BloQcs design by Bloc
SMF 2.0.2 | SMF © 2011, Simple Machines
SMFAds for Free Forums
TinyPortal © 2005-2012
Page created in 0.14 seconds with 49 queries.