Thursday, May 26, 2016

1. Introduction

Updated July 11, 2018
(This blog is written with reference to the 2-bladed head version - BLH3450).

Early in 2016 I purchased my first (pre-owned) Blade 180 CFX that was in need of some minor repairs.  After tearing it all down, replacing worn or broken parts, reading up on the forums, asking all kinds of questions and then rebuilding it, I managed to log over 100 flights in about 2 months.  In doing so I've learned a few things about the heli and it's components:  It's FAST, extremely sensitive to cyclic inputs, and yet VERY configurable.

Most of what I learned wasn't mentioned in the manual or on Horizon's or BladeHelis' websites.  I've also stumbled across a not-so-obvious thing you can do with this heli - fly it with a 2S pack (thus lower RPM) in addition to 3S.  However, you must make some adjustments to the Talon15 outlined here or your heli won't ever get off the ground with a 2S pack.
Now, haters are gonna hate, period.  I'm just being honest here.  First, there's absolutely no reason to continue reading if the thought of taming down a HOT collective pitch 3D RC helicopter offends or pisses you off.  I took some shit years ago for taming my Blade 400, but after speaking to and flying with Dwight Shilling earlier this year (2016) I learned these are the same types of things FAI/F3C pilots do to their helis in order to compete in precision hovering maneuvers.  Go figure - there are other things you can do with CP helis besides smack 3D and redlining their power systems.

Second, there's this:  "It's a flying PIG" ... "It's disc loading is too high" ... "It's lethargic" ... "No way will it  fly at lower head speeds" ... MY ASS!  Sure, if you've bling'd it out with 75+ grams of 'upgrade' metal parts, belt drives, fiberglass canopies, oversized batteries, metal cased/geared/larger servos, 3rd party FBL controllers and ESCs, or Goblin-like fuselages.  If you've done this then I'm afraid you're out of luck.  Your 'customized' heli will need the highest possible RPM just to get airborne.  Lowering its head speed makes absolutely no sense in this case and will only make things worse.  Here's a dead nuts on prediction back from October 14, 2014 regarding the soon-to-be-released 180 CFX from ToddMcF2002 on Helifreak:
  • "The biggest flaw is that it will attract noobs who crash constantly, can't repair properly, buy pointless upgrades and call it a high maintenance money pit.  It is foretold."
Finally, don't think for a minute this heli is 'crippled' or 'bogged down' flying on 2S.  Here she is with a 31g 2S 7.4V 500mAh pack, 3100/3300 RPM.  Sure felt 'floaty' to me:

Enough said.  If you haven't rolled your eyes and left, let's get started!

All CP helicopters can be tamed down by doing any of the following:
  1. Using a pinion gear with less teeth.
  2. Using a main gear with more teeth.
  3. Using a motor with lower kV.
  4. Using a battery pack with fewer cells.
  5. Reducing the main and tail rotor RPMs.
  6. Setting Dual Rates for cyclic and rudder.
  7. Using Expo for cyclic and rudder.
  8. Reducing and adjusting (dual rate-like and expo-like) collective pitch range.
We'll be exploring #'s 4, 5, 6, 7 and 8 here.  A stock heli (or one close to stock) works best as keeping the AUW (All Up Weight) as low as possible will yield the absolute best results.  AUW of a stock 180 CFX is around 190-195g, so that's the goal to keep in mind.

The 180 CFX isn't really a beginner's helicopter in that it is configured with really high head speeds (4000 - 5000 RPM) and incredible cyclic and collective pitch responsiveness right out of the box.  It's ready to fly smack 3D as soon as you get it home and is basically a modern day 450/550/600/700 size flybarless helicopter miniaturized down to a 180 size, minus an auto-rotation gear and one-way-bearing.  However, it doesn't NEED all of that power and responsiveness in order to fly well as other helis do.  It has a LOT of RPM overhead and a LOT collective/cyclic pitch range to make flying smack 3D easier.  It's got a moderate disc loading of 1.86kg/m².  Even better, since it was designed for extreme performance and abuse, it's overall mechanical and electrical design becomes overkill once you slow it down, meaning it's extremely reliable and predictable for those just starting out or those who prefer to not push the envelope.  That being said, some respectable experience in building, setting up, maintaining, repairing and flying collective pitch helicopters is really required to get the most out of this 'fun-size' heli.  This was my first flybarless helicopter and first exposure to Castle Creations ESCs, so I had some catching up to do.

Over the next few pages I'll explain some things that kept me scratching my head at first.  Then I'll show you how to turn this ballistic 3D machine into an easygoing heli you can fly casually in your back yard or take to the field and do some sport and aerobatic maneuvers. We'll go from 3 minute flights to 5, 6, even 7 minute flights.  We'll be doing this without changing pinion gears or motors.  Instead we'll use the heli as it comes stock changing only the battery pack, transmitter settings (throttle curves, pitch curves, dual rates and expo) and re-configuring the Talon 15 ESC.  We'll even set it up so it's easy to switch back and forth between ballistic and easygoing.

Just to be clear, everything in this blog assumes a stock 5800kV motor, with 6 poles, a 10T pinion and a 104T main gear.  Also a stock heli close to the 190-195g AUW with 2S and 3S lithium-polymer packs in the 30-46g weight range.

Stay Safe
Even at 3000 RPM this heli can hurt you, badly.  Remember, the tail blades spin approximately five times faster than the main blades, so when in ballistic mode at 5000 RPM the tail is spinning at 25,000 RPM!  At these RPMs the main blade tips are traveling at 211 miles per hour while the tail blade tips are traveling at 268 miles per hour !!!  This can do SERIOUS damage to the human body.

Please! Be sure to adhere to all RC helicopter safety precautions when operating the Blade 180 CFX.