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doulos24
10-07-2011, 01:36 AM
I crashed my 450 clone today before getting it off the ground!

someone set it up for me in the radio and it was to fast of a throttle curve for me and way to twitchy the thing lifted up 1/2 an inch and the blades struck the ground from behind. I can see I have a twisted tail, the blades are gone, the landing gear broke, the elevator servo stripped, the tail control wire is bent plus the tail support bars broke

my question is how do I check the less obvious like the main shaft, the feathering shaft ,the shaft in the tail to make sure there not slightly bent which could cause another crash???

Larry227
10-07-2011, 02:02 AM
Best way to check the shafts is to pull them out and roll them on a flat surface such as glass. If they're bent you will see it. With the damage you mentioned I say it's a 99.9% chance that all three are bent.

whiskykid
10-07-2011, 09:49 AM
training gear!:face

j32driver
10-07-2011, 10:08 AM
Guess what? You get to do a complete build! :D I'm serious. I'm doing the same thing right now. In order to get the elevator servo out, you pretty much will need to strip the helicopter and pull the right carbon fuse plate off, then pull out the gears, main shaft and head assembly. Then you will need to free the top bearing block from the left frame so you can lift out the elevator servo.

As a prelim inspection:
Main shaft... does the head button wobble when you rotate the head?
Tail shaft... rotate the head to spin the tail rotor. Watch the tail slider assembly really close. Does it wobble ANY at all?
Feathering shaft: Obvious damage will show up as the main blade grips aren't lined up like they should be. Best thing here is to pull the blade grips off, then pull out the feathering shaft and roll it on a perfectly flat surface like a piece of glass.

What about the main gear? Any missing teeth?

Since someone else built this and set it up for you, you will need to download the appropriate Align manual for you clone. If you are running a clone of a Pro with a belt drive, understand the heli is a mash up of 2 different Align birds. Everything is Pro until you get to the tail drive and boom. Those pieces are the same as the 450 SE V2.

Once you figure out what is busted, you get to rebuild. Yours is going to be almost a complete rebuild to include radio setup. You will need to watch and understand the CCPM 1 and 2 vids that Finless did.

This is going to be a long process for you with a steep learning curve. BUT... once you figure out how to build the heli, crashing won't seem so bad.

If it makes you feel any better, I flew my clone about 50 flights before my 1st crash. Then I got 4 flights in before I stuffed it vertically from about 20 feet up. :face

Ask all the questions you need. We are here to help get you back in the air. :cheers

squeky
10-07-2011, 11:39 AM
Feathering shaft: Obvious damage will show up as the main blade grips aren't lined up like they should be. Best thing here is to pull the blade grips off, then pull out the feathering shaft and roll it on a perfectly flat surface like a piece of glass.


A quick check on the feathering shaft is to take the blade off, put a hex key on one side, and turn. If the grip rotates, it's bent.

To the OP, don't blame the throttle curve. Head speed is your friend and will stabilize the heli. Look at other things to tame like flybar weights, expo, and get some training gear!

doulos24
10-07-2011, 02:47 PM
I had training gear on it and I wasn't trying to fly i was trying to check the swash an blade tracking at low rpm but the guy that set up my radio set up the throtle with a steep curve and it tiped over.

j32driver
10-07-2011, 07:08 PM
I had training gear on it and I wasn't trying to fly i was trying to check the swash an blade tracking at low rpm but the guy that set up my radio set up the throtle with a steep curve and it tiped over.

Post up the pitch and throttle curves that the hobby shop guy programmed for you. We will be able to better help you.

doulos24
10-08-2011, 04:26 AM
thro curve 0 50 80 88 99

pitch 0 62 81 86 90

j32driver
10-08-2011, 01:08 PM
thro curve 0 50 80 88 99

pitch 0 62 81 86 90


Throttle curve will work just fine. Your pitch curve, in my humble opinion, is JACKED!

What Transmitter are you using? I would expect that you should have several pitch and throttle curves programmed.

Normal: This is what you will use to take off and land with.
Stunt 1: After you learn how to hover, stunt 1 can be programmed to allow inverted flight.
Stunt 2: Usually just like Stunt 1, but with higher power
Hold: This is the pitch and throttle curves you want when you turn on Throttle Hold. TH will override all other pitch and throttle curves when activated.

Let's start with the NORM throttle curve. With the 450 size, the higher the RPM, the more stable the helicopter is. Find a head speed calculator on line, feed it your info, and get a rough idea of what your rotor RPM is at a given throttle %. A good comfortable RPM for this heli is 2800-3000 RPM. Any slower than that, and you start to loose stability. Any higher, and you wind up with more power than you will really use right now. For now, I'm going to assume that 80% puts you in that range. If that is so, I would make your Norm Throttle curve this:

0-50-80-80-90

Now lets match up a good pitch curve to that. We aren't going to be flying upside down in NORM mode, so we don't need much negative pitch on the blades. 2-3 degrees negative will be plenty. If you have a max of +-10 degrees pitch available, then every 5% in your transmitter equals 1 degree of blade pitch. 50% is the middle of the curve, or 0 degrees pitch. If we want -3 degrees of pitch as the start of our curve, then 50-15 gives us a 35% setting for the low point on the curve. People generally want midstick to be 0 degrees of pitch... translated that means 50% on the curve. Halfway in between 35 and 50 is roughly 43 for menu purposes. That means we now know the 1st three points in our pitch curve:

35-43-50

I wanted the top half of my NORM pitch curve to match in STUNT 1 and 2. I want full travel in those, so that means the next two numbers are 75 and 100. So your NORM pitch curve would look like this:

35-43-50-75-100


Stunt 1 and Stunt 2 are all about having the heli upside down. We want max power and max pitch at the top of the stick, and max power and minimum pitch at bottom stick.

Throttle Stunt 1: 90-80-80-80-90
Pitch Stunt 1: 0-25-50-75-100

Throttle Stunt 2: 100-95-95-95-100
Pitch Stunt 2: 0-25-50-75-100

With this curve setup, you will be able to switch between NORM, STUNT 1, STUNT 2 without the heli making a noticeable jump or jerk while in the air.

The last set of curves you need to program is HOLD. Most people use this as a no power flight mode.

Hold Throttle: 0-0-0-0-0

Your hold pitch curve should probably be the same as the mode you intend to fly most in. If you are just starting out, make it match your NORM pitch curve:

Hold Pitch: 35-43-50-75-100

As you advance and start flying more in STUNT 1 and STUNT 2, you might consider making your HOLD PITCH match your pitch in STUNT 1 and STUNT 2.


These curves are how I do it. Everyone is different and you may like something else better. But these will safely get you in the air.

doulos24
10-08-2011, 05:35 PM
turnigy 9x transmitter is what I have. I'm rebuilding a new 450 as we speak. I didnt trust my ability to rebuild so I started from scratch.Carbon fiber fame all cnc metal tail and head unit same electronics etc. I'm almost to the point where I'm setting up the ccm section proably tomorrow on that.

j32driver
10-08-2011, 08:46 PM
turnigy 9x transmitter is what I have I'm rebuilding a new 450 as we speak I didnt trust my ability to rebuild so i started from scratch carbon fiber fame all cnc metal tail and head unit same electronics im almost to the point where im setting up the ccm section proably tomorrow on that

http://i1132.photobucket.com/albums/m567/chipav8s/url.jpg

Sorry. I just couldn't take it anymore. :D

Gadflyii
10-08-2011, 11:17 PM
Are you just learning to hover?

If so try this:

Normal mode throttle curve
0,35,60,65,70


Pitch curve is ALWAYS the same:

Normal
45,48,50,75,100

All stunt modes:
0,25,50,75:,100


Drop some flaybarless weights on it, use heavy wood blades, daily in +20 EXPO, and your DR to 80%

Instant trainer :)


ZOMG... internets!