HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Sep 30, 2011, 04:48 PM
Crashing into the sky!
jackosmeister's Avatar
Auckland NZ
Joined Aug 2007
7,174 Posts
Whats wrong with a gearbox? No point calculating much until you know the how much load the prop is.
jackosmeister is online now Find More Posts by jackosmeister
Reply With Quote
Sign up now
to remove ads between posts
Old Sep 30, 2011, 04:55 PM
Livin it UP when Im goin DOWN
Arcteryxxx's Avatar
Norway, Telemark, Skien
Joined Feb 2010
4,255 Posts
No point in ANYTHING unless something is decided upon... If the goal is pure speed...I know 3kW on a square pylon prop would bring a smile to my face....
But I'm more into climbrate and other boring, accounting type specs....
Arcteryxxx is offline Find More Posts by Arcteryxxx
Reply With Quote
Old Sep 30, 2011, 05:07 PM
"The Judge"
sebbe's Avatar
Sweden
Joined Feb 2006
5,758 Posts
Quote:
Originally Posted by Arcteryxxx View Post
The laws of physics will be your constraints anyhow, although even Einstein is challenged these days
Look for battery capacity, ESC and motor efficiency and decide on prop and the necessity of custom made components as you thoroughly document your findings along the way.
The Stryker speed record (Murdnunoc) at 204mph average was achieved by doing things scientifically.. You will never stumble upon a world record by accident. There are too many bright guys in this hobby to make that possible....
sure, you wont break the world record just guessing...

But how may has put a 5s lipo 55c in a fast airframe F5D @3kw using a carbon propp 7x13 made by Marcus ?

How fast has any F5D or Pylon been at yet, 350km/h , 360km/h ?
This is where there is a wall with a normal pylon sqaure propp, if you want to go faster you will have to change sometthing..

I dont think there are so many wackos like me trying these stuff..
well a few in this thread, haha..

I will give it a GO... Once again, what motor ??

maybee ARC 36mm inrunner ?

or better a MEGA 36mm inrunner..
sebbe is online now Find More Posts by sebbe
Last edited by sebbe; Sep 30, 2011 at 05:13 PM.
Reply With Quote
Old Sep 30, 2011, 05:13 PM
Crashing into the sky!
jackosmeister's Avatar
Auckland NZ
Joined Aug 2007
7,174 Posts
28mm inrunner. KPG gearbox. Lot of voltage to get the rpm. Use the voltage luke
jackosmeister is online now Find More Posts by jackosmeister
Reply With Quote
Old Sep 30, 2011, 05:17 PM
"The Judge"
sebbe's Avatar
Sweden
Joined Feb 2006
5,758 Posts
I think Scorpion-fan has something right here:

the real reached speeds are about 75% ("bad" aerodynamic properties) to 85% (very good aerodynamic properties) of pitch speed.
this is the first point - found by using real data, not with only theoretical abstractions.

second: blade tip speed has to stay slower than 0,8mach.
with these 2 data you can find out out, where the "square" prop finds his border.
with less than 0,8 or 0,75 mach you are able to go round these problems just like in f2a.

want you to be faster, you need an oversquared prop.

--------------
sebbe is online now Find More Posts by sebbe
Reply With Quote
Old Sep 30, 2011, 05:20 PM
"The Judge"
sebbe's Avatar
Sweden
Joined Feb 2006
5,758 Posts
Quote:
Originally Posted by jackosmeister View Post
28mm inrunner. KPG gearbox. Lot of voltage to get the rpm. Use the voltage luke
I know, but I want to limit to 5s lipos....
sebbe is online now Find More Posts by sebbe
Reply With Quote
Old Sep 30, 2011, 05:30 PM
Crashing into the sky!
jackosmeister's Avatar
Auckland NZ
Joined Aug 2007
7,174 Posts
Your 40/2 may well work direct drive. Just start on 3S and work up keeping an eye on temperatures and rpm. As long as your loaded rpm doesnt take a big nose dive at a certain voltage point, and you keep the mega cool. Load it up with heatsinks etc, I rekon it'll work.

Remember to post your numbers. I have a 16/40/1 that has been pencilled in for something silly fast too ( maybe Yuri's new project )
jackosmeister is online now Find More Posts by jackosmeister
Reply With Quote
Old Sep 30, 2011, 06:27 PM
One Idiot is plenty...
Dbox's Avatar
Planet Earth
Joined Jun 2005
5,114 Posts
Quote:
Originally Posted by jackosmeister View Post
something silly fast too ( maybe Yuri's new project )
I am working on it.
Will be available coming winter
Yuri.
Dbox is offline Find More Posts by Dbox
Reply With Quote
Old Sep 30, 2011, 07:08 PM
Crashing into the sky!
jackosmeister's Avatar
Auckland NZ
Joined Aug 2007
7,174 Posts
Was planning on trying 5S tommorrow, weather is packing in though

Roll on summer..


Any pics and details of the UberX Yuri?

Is it feasible to make a 30mm nosed X for F5D power systems? Even a carbon nose extension that could be stuck on would make fitting an F5D system easy.

Oh and I still want a really light "sport" X too.


Want want want
jackosmeister is online now Find More Posts by jackosmeister
Reply With Quote
Old Sep 30, 2011, 08:10 PM
One Idiot is plenty...
Dbox's Avatar
Planet Earth
Joined Jun 2005
5,114 Posts
New fuse plug sits on separation board for about three month by now.
I simple have no time for anything ,including my own "X".
Fortunately/unfortunately weather is going South and I will have more time for the projects.
Yuri.
Dbox is offline Find More Posts by Dbox
Reply With Quote
Old Oct 01, 2011, 04:29 PM
"The Judge"
sebbe's Avatar
Sweden
Joined Feb 2006
5,758 Posts
Jacko, first I have to decide wich plane,, maybee the X isnt the most ideal plane for my project, I think the PILF will be faster (more aerodynamic).. but thats 400 euros just for the plane, and I have not yet starting to build my Stiletto, my Xplane or my VIPER, I just buy and buy and never build them, haha,,,,, What my problem, maybee I should not buy more fast planes..

we will see, I also think the mega 40/2 could be a good motor for my thoghts..
sebbe is online now Find More Posts by sebbe
Reply With Quote
Old Oct 01, 2011, 04:38 PM
200mph +
sykotic's Avatar
New Zealand, Manawatu-Wanganui, Palmerston North
Joined Sep 2010
930 Posts
When are you taking preorders yuri?


Flew the x with the tail sorted yesterday. Sweeeeeeeeeeeeeet plane.

Need to put in the 5s already Jacko :P
sykotic is offline Find More Posts by sykotic
Reply With Quote
Old Oct 01, 2011, 05:08 PM
Crashing into the sky!
jackosmeister's Avatar
Auckland NZ
Joined Aug 2007
7,174 Posts
I dunno how the pilf is more aerodynamic sebbe. Go build and fly ya X and then ask yourself that same question

The X is THE best flying go fast plane I have, it tracks like its on rails, but feels very precise and nimble at the same time. Also feels epically strong in flight, havent seen the wings bend yet

Glad you got your sorted Brad, ready for a race now?
jackosmeister is online now Find More Posts by jackosmeister
Reply With Quote
Old Oct 01, 2011, 05:20 PM
Crashing into the sky!
jackosmeister's Avatar
Auckland NZ
Joined Aug 2007
7,174 Posts
BTW, What does F5C involve? Maybe we should give it a go
jackosmeister is online now Find More Posts by jackosmeister
Reply With Quote
Old Oct 01, 2011, 05:54 PM
200mph +
sykotic's Avatar
New Zealand, Manawatu-Wanganui, Palmerston North
Joined Sep 2010
930 Posts
Isn't it the same as F5B but with different plane size limits and watt limits?
sykotic is offline Find More Posts by sykotic
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Blade MCP X - owner's thread rchelijc Micro Helis 12978 Jul 01, 2014 11:15 PM
Discussion MCP-X thread for people that dont have a MCP-x axelen Micro Helis 186 Apr 01, 2011 01:17 AM
Data mCP X (non chat) setup and tips owners thread Cable Guy Micro Helis 9 Mar 12, 2011 11:50 AM
Build Log Build Log - ARK X-500 series build thread cfrank2005 Electric Heli Talk 30 Jun 29, 2009 12:27 PM
RBC A-4 Skyhawk build thread X.X Willmsy Electric Ducted Fan Jet Talk 6 Nov 22, 2005 10:01 PM