Fun, Learning, Friendship and Mutual Respect START  HERE

Go Back   HeliFreak > R/C Helicopter Support > Scale Helicopters > Power Systems

Power Systems Power Systems Discussion

LinkBack Thread Tools Display Modes
Old 02-19-2014, 05:38 PM   #1 (permalink)
Registered Users
Posts: 3,698
My HF Map location
Join Date: Nov 2011
Default Blade length, Main gear and pinion

As I am going to be using my Trex 550E V2 in a scale body
I have a set of beautiful 560mm CF blades about an inch longer than stock and would like to use them.

Anyone know of a calculator available for calculating load and current requirements
gear and pinion selection for blade length?

I'm not going to be doing 3D with it so I figure running a little longer blade in the 2000 RPM range should give the helicopter plenty of lift? But I'd like to keep the motor wound up so it's not bogging or drawing excessive current

Any advice would be great.
Petrolia Ontario Canada.
Electric, MCPX-BL,450X, Trex 550E Nitro Hirobo SCEADU Evolution 50

Last edited by Imzzaudae; 02-19-2014 at 07:31 PM..
Imzzaudae is offline        Reply With Quote Quick reply to this message
Sponsored Links
Old 02-19-2014, 09:03 PM   #2 (permalink)
HF Scale Support
Posts: 3,962

Join Date: Jan 2010

Hi. You are currently running the 16t pinion and 170t main gear as normally equipped on the V2's I presume. Also, you have the1220kv motor as supplied. The smallest practical pinion you should use is the 13t with the gearing and motor you have. Your alternative is to lower the kv of the motor to something around an 890kv rating and keep the pinion or drop it by one tooth to the 15t. For scale application of a 550 chassis, 2000 rpm is much too high and most will use anywhere from 1450 to 1600rpm at the most. Using 560mm blades will also put more load on the gearing and you might find that the tips of the blades could, in an extreme move or hard landing, make contact with the tail rotor blades. I run 550mm blades on a Jet Ranger and they have enough clearance from the tail rotor. In fact, I just measured the distance from the tail blades to the bolt hole and it is 550mm. In other words, even I need to mind my hard landings or the mains could clip the tail blades if they happen to exactly line up. Hope this helps.

Keyrigger is online now        Reply With Quote Quick reply to this message

Quick Reply

Register Now

In order to be able to post messages on the HeliFreak forums, you must first register.
Please enter your desired user name, your REAL and WORKING email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself. Use a real email address or you will not be granted access to the site. Thank you.
Email Address:
Where do you live? ie: Country, State, City or General Geographic Location please.
Name and Lastname
Enter name and last name here. (This information is not shown to the general public. Optional)
Helicopter #1
Enter Helicopter #1 type and equipment.
Helicopter #2
Enter Helicopter #2 type and equipment.
Helicopter #3
Enter Helicopter #3 type and equipment.
Helicopter #4
Enter Helicopter #4 type and equipment.


Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Copyright © Website Acquisitions Inc. All rights reserved.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.

SEO by vBSEO 3.6.1