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Burgess
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PostPosted: Mon Apr 13, 2015 1:12 am
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Well spotted there Mark, the top ‘A' links must have been fitted crossed over.

Glad to have been of some help.


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Burgess
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PostPosted: Mon Apr 20, 2015 10:23 pm
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Mark can you give me some feed-back regarding the settings relative to the tail rotor:

#1 Gyro pot settings: Limit and gain percentages
#2 Position of link-ball on the servo arm
#3 Preset pitch angle of the tail rotor when in Idle Up flight mode.

Transmitter Settings for rudder Channel 4 and Gyro Channel 5

If you're using training gear, take care it doesn't throw the heli out of balance. Check the CoG from side-on and nose-on with the training gear in place from side-on and nose-on.
Support/suspend the heli from either side if the flybar control cage.

Side-on, the boom must be dead horizontal
Nose-on, the main blades must be dead horizontal.
Adjust the battery position to rectify.
Even the slightest amount of out of balance will cause the heli to drift-off in some direction.


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Burgess
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PostPosted: Wed Apr 22, 2015 9:15 pm
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Mark, if you haven't yet then invest in a set of training gear and use it during your initial setting-up, it will allow you to see if cyclic needs adjustment check CoG first, if ok then check Aileron and Elevator trims. It will protect the heli during early learning curve lift-off and landings.

Gradually increase the throttle, the heli will become light, the skids lift off the ground and the heli is free to tilt so any cyclic out of trim will become apparent.

As your still learning to get off the ground and back down in one piece, and your not going to need full throttle for a little while.
Re-set the throttle curve to provide a more constant head speed up through the mid-stick position as this is where you'll be for a while.

With a linier pitch curve and a linier throttle curve everything changes very quickly. So what you need for now is time to think and react.
Reset the throttle curve, 00; 45; 55; 65; 75.
You could also lever-off the top end of the pitch curve in Normal flight mode, 55; 62; 75; 75; 75. So with very little pitch variation this will give a much gentler decent. For now you don't really need to be much higher than head height. As the need to think of what to do disappears, revert to linier pitch curve and 100% for full throttle.

Also you need to soften the cyclic control response, either by programming in some Expo (exponential) for the cyclic channels, this slows the servo response to stick input. Or reducing the Aileron and Elevator Endpoints.

Once you've got your heli setup don't be in a rush to go flying high and wide across the sky, you need to do orienteering lift-off and landing with the nose pointing in any direction and that can be a real mind bender, especially Nose-In, so training gear is a great investment.

If you could run to a Spectrum DX6i receiver for the Hausler setting-up would be sooooo much easier and so-to using just one transmitter for both helis. The problem of having more than one type of transmitter and control lay-outs is thinking time delay.

The Flysky CT6B is a real pain as you've to keep hooking up to the computer to reset anything. It's OK as an entry level radio system.

Any clone T-rex450SEV2, the hausler being such, are really good helis once set-up.

After a heli crash inspect all shafts and bearings main, feathering, tail rotor, maybe the motor shaft, and not forgetting the flybar.
A cogging bearing will cause problems.

Cheep bearing can be more trouble than the little saved purchasing them.

Check shafts and booms by rolling on plate glass and if there is literally any distortion then replace it.

So for gears, shafts, and bearing I always purchase Align. OK so they cost more but a smooth running heli is easier to setup and fly.




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marks73
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Location: Leland, NC. USA

PostPosted: Thu Apr 23, 2015 7:17 pm
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I have 2 sets of training gear. One is quite heavy but does have a pivot in the center that allows me to see if the heli is trying to move one way or the other on lift off. It has a plate that slides through the skids and it has the heli about 4 inches off the floor. I use it indoors to check my set up. The other straps to the skids and is much lighter so I've been using it outdoors for flight to conserve the battery.
As for throttle curve, I'll set it up that way. Any recommendations on a receiver for the spectrum?
Feel like I should be paying you tuition! Laughing
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Burgess
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PostPosted: Fri Apr 24, 2015 5:37 am
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We like to help.

Check your transmitter modulation type (early) DSM2 or DSMX (latest)
here's a link to Spectrum which explains:
http://www.horizonhobby.co.uk/aeroonline/e6spektrum/e6overview/e6_dsmx_about.html
Hopefully yours is DSMX and the Spektrum AR610 6-CH DSMX appears to be widely available shop around for a good deal.

For instance see www.kingslynnmodelshop.co.uk
Not sure what their delivery charges would be for State side.

Spektrum AR610 DSMX 6 Channel Receiver
RRP: £49.99 on offer at Price: £41.90

Spektrum AR610C 6-CH DSMX Sport Aircraft Coated Receiver
RRP: £49.99 on offer at £29.90

Spektrum AR610 DSMX 6 Channel Receiver - Unboxed
SmartSafe technology provides low-throttle failsafe in the event of lost RF signal
RRP: £49.99 on offer at £25.90

One available on ebay for £23.93

Then there is the Orange Rx R615X they're compatible with Spectrum DSM2/DSMX and cost much less.

Tom and Keith both use Spectrum maybe they can make a recommendation too.


Here's a couple of informative videos:

DX6i & CCPM Full Setup Guide Part 1 Setting Up The DX6i
http://www.youtube.com/watch?v=uxWhzYzMEPY

Stick Calibration
http://www.youtube.com/watch?v=o8gU_x3vBBw


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marks73
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PostPosted: Fri Apr 24, 2015 6:54 am
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Yes, Mine is a DSMX. I'll research the receiver you recommend.
I had a feeling there was an easy way to calibrate the transmitter. Thanks for the videos. They'll come in handy. Figure since I have the thing I need to start using it for more than just a flight simulator transmitter.
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marks73
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PostPosted: Fri Apr 24, 2015 8:13 pm
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The ZD720 Gyro is set up as follows:

Delay 70%
Limit 100
DS is ON I'm using a Turnigy S306G=HV Tail Servo
Reverse is normal

I set the tail blade pitch just off center with slider closer to the boom by moving the servo until the tail would stay strait after initial spin up on my trainer that is capable of pivoting in the center. The link ball is attached to where the rod was even height across the boom which was second hole from end of servo arm with the arm 90deg.

Channel 4 is reversed
Channel 4 is end point 80,80 sub trim 0 DR 100,100 Mix 2 is channel 4 to channel 4 at 100 and 100 with switch on.

Channel 5 is end point 100,100 sub trim 0 Mix 1 Source VR B Des 5 100,100

I believe you are correct on some of my hovering issues are due to training gear CoG. My lighter training gear does seem to move around the skids being that it is only tie wrapped on. Maybe I should stick with the heavier training gear that has 2 bolts with wing nuts through a top and bottom plate and holds the craft tight?
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Burgess
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PostPosted: Sat Apr 25, 2015 8:39 am
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Keep with the light weight training gear -keeps airborne weight down- try using zip-ties to anchor/rig-sling the centre of the training gear to the under side of the bottom plate of the frame. Check the CoG from side-on and nose-on with the training gear in place. Support/suspend the heli from either side if the flybar control cage. If anchoring the training gear was successful, the adjust the battery position to obtain good CoG.

The TGY-306G is a fast responding strong digital servo so you can set the Gyro delay to 0%.

Turn transmitter VR(B) CW for Head-hold (Normal), turn CCW for Rates mode (Idle Up).
Set to 2 O'clock to ensure the gyro is in head hold mode before connecting the battery. When the battery is connected the gyro LED should flash during initialisation then go sold indicating head hold. If you turn the knob CCW the LED goes out indicating the gyro is in Rates mode.

In Channel 4, the end point settings controls speed of reaction to Rudder stick movement rather than the travel deflections of the servo, the Limit pot on the gyro does that.

Two things to keep in mind:
i) Ideally the more the servo arm can deflect in either direction, the greater the control resolution will be. So the link-ball need to be about 8mm out from the centre of the servo output arm, and preferably on the outer side of the arm to prevent bind-up on the servo arm hub.

ii) the steering slider must not bind-up against either the tail gearbox or the hub of the tail rotor.


Next Set the tail rotor Neutral Position:

Energise the receiver after the gyro led goes solid,
Release the servo support clamp screws just enough to permit the servo-support assembly to slide along the boom till the angle of the tail rotor blade to about 5 positive pitch.
The leading edge of the upper blade facing to your left when viewed from behind. Use your pitch gauge set it to 5 degrees positive pitch and place onto the blade so as to aline the top of the gauge with the boom. Tighten-up the servo-support assembly clamp the screws.
Check for any bind-up against the gear box and reset travel via the gyro limit pot if needs be.


Dynamic test
Reconnect motor leads, set VR(B) to 2 O'clock,
energise the receiver,
when gyro has initialised rotate VR(B) to 12 O'clock (LED out)
Spool-Up,
If the nose turns right ease the rudder servo assembly backwards.
If the tail waggs quickly increase the Gyro Delay percentage in small steps until the tail holds steady. Tighten up the servo support boom clamp screws.
Power down disconnect the battery, reset VR(B) to 2'O'clock and reconnect the battery let gyro initialise then turn VR(B) til the LED gos out spool-up just enough for the heli to become light on the training gear. If the CoG is directly under the main shaft, the heli should begin to move to your right, this is normal. Counter with a light touch of right cyclic and increase the collective the heli should lift and the tail should hold steady. Ease the collective down and the tail should remain steady as the heli sets down.

Spool-up again heli till light on the gear and in contact with the ground, and give gently try the rudder control left and right, the tail should respond with out delay. Try increasing the amount stick movement, if the tail responds too quickly then reduce the end points to slow it down.




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marks73
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PostPosted: Sun Apr 26, 2015 6:39 pm
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As to the endpoints of channel 4. Are the left side numbers for left rudder speed and the right ones for right? Or do I need to keep them both the same value? What is a good setting to train by until I can get the feel for this touchy transmitter.
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Burgess
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PostPosted: Mon Apr 27, 2015 2:33 am
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Yeah, channel 4 endpoints...left for left, and right for right, yes have both at the same value. Keep then at 80/80 and when you've got the CoG dead under the main shaft and zero fore-aft, left-right drift, spool up and get the heli light on the training gear and gently feed in progressive rudder-stick input. If the helicopter wants to accelerate into a fast spin, reduce both left and right values by say 10% to 5%, repeat if needs be to what you feel comfortable with.



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marks73
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PostPosted: Mon Apr 27, 2015 8:05 pm
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I'm about done on the rebuild. Turns out that last crash did more damage than I first saw. When the bird came down on its tail and then its side I saw the bent tail boom and flybar. Turns out it also:
bent the feathering shaft
Chewed the drive gear
Broke the motor shaft clean off
I've got the spare parts and have it almost ready to place back on the trainer for balancing and the transmitter changes.
I'll let you figure what this months tuition payment should be. Very Happy
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marks73
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PostPosted: Sun May 03, 2015 5:29 am
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Finally finished this rebuild. Awoke to a clear and windless morn with 2 grandsons pointing out the same and "Can we try it today?!!!" been raining here for three days.
Replaced the motor off of the spare clone I bought from a man on ebay who admits he didn't know who made it either but it was almost identical to my Hausler other than an all metal rotor and tail assembly.
Installed a new tail boom, feathering shaft, and balanced up my last set of new blades (the Align 325 fibers) and checked COG after tie wrapping the training gear down.
I had went over all the screws while rechecking the level of the swashplate. Verified 5.2 deg on tail blades and good + and - pitch on mains .
So, power it up in head hold and then turn VR B to about 12 O'clock and put in rate. Rotten rascal wants to tail spin slowly but continuously to the left and full body drift left and back at same time.
Only using the sub trims I was able to stop the backward drift and most of the to the full body left but unable to stop the tail spin left.
Field adjusting the tail servo to try to stop the left tail spin and at least get it to go to the right a bit without giving up all tail pitch positive was unsuccessful and the left full drift of the body returned. Gave up after about an hour of not being able to control it after getting airborne and a steady hover. It acted like it wants to start to flip onto it's right side at about 3 feet high.
Is it possible knowing the main frame has 4 parts on the sides that I have skewed the frame screws? I can't find any cracks. Seems the only thing I haven't checked out yet after the initial power up crash?
The Spektrum receiver came in the mail today and the Emax servos will be the last pieces I need to assemble the Align Pro and I believe they'll be here Monday. I have the new Assan GA250 gyro that was recommended as well.
Should I just park the Hausler and Flysky and begin anew with the Pro and the Dx6i?
Frustrated rebuilding the Hausler though no damage done today. Very Happy
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Burgess
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PostPosted: Sun May 03, 2015 10:04 am
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Well done Mark if you've managed to liftoff and land the Hausler while out of trim that has to be a big plus. Setting-up and dialling can be very frustrating, it's all part of the learning curve, SO stick with it.

First check over the main rotor assembly very closely.
Verify the that length of the B link-rod pair -washout mixing arms to flybar control frame- are set to identical lengths; and from the paddle end-on the frame is at right angles to the main shaft.
Important, the paddles MUST be absolutely parallel to each other and at right angle to the main shaft.
So ensure cyclic sub-trims are 0% and Trims are central.

Drop the main blades off if you've used tracking tape on the blades, then index at least one blade holder so you replace the blades in the right blade holders.

Next check the main rotor for adverse interaction.
Disconnect two motor leads:
Energise the receiver, after gyro has initialised in Head-Hold, set one paddle to Port support the flybar loosely between finger and thumb, and in Normal flight mode slowly move the collective up through the half stick position and slowly back down while observing the paddle, which should remain completely horizontal. Do likewise with the paddle straight ahead.

Deflections when the paddle is to port: if the leading edge goes up the heli will tend to drift backwards, if down the drift will be forwards.
Deflections when the paddle is straight ahead: if the leading edge goes up the heli will tend to drift leftwards, if down the drift will be rightwards.

Next: focus on getting the tail to hold steady. Only need to get light on the training gear or just free of the ground.

As your using that Turnigy digital tail servo set the ZD720 delay right down to 0%, energize the receiver with the gyro in HH, revert to rates mode and spool-up. If the tail fast-wags increase the delay in small amounts till the wag just stops.
Adjust the position of the tail servo assembly along the boom in very small amounts till the tail hold steady.
Tighten-up servo assembly boom clamp screws.
Power off and energize in head hold and normal flight mode.
Spool-up and as the heli comes light it should slide/move to the left, but not forward or backwards, use elevator Trim (not Sub-trim) one click at a time to correct.

If you cannot sort it with the Flysky, then install the Spectrum receiver and free yourself from the need to hook-up to the computer to make changes.
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marks73
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PostPosted: Sun May 03, 2015 7:15 pm
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I misspoke of subtrims. I actually meant transmitter trims. The right stick trims appear to work well with only a few clicks between stopping forward and backward movement and the drifting left I ran out of trim. The left stick rudder trim however seems to do as it pleases.
I will say the grass was a bit high for the balls on the trainer and they did at times hang up in it. We did keep moving it to clearer spots though as we kept trying to work out a good hover.
Just how many feet of movement is considered a "good hover"
I felt like I had good blade tracking. Though I must admit I forgot to change to the pitch curve you recommended. I'll do that as well as the other things you recommend tomorrow while the kids are at school and see if I can't get this thing straitened out. Been a challenge but a great learning tool. And the boys (12 and 7) seemed to learn quite a bit as far as power off, adjust, throttle hold, tx power, battery power, head hold rate mode, and safe distances to test. Especially the 7 year old. As we walked back home he said "We were so close. You'll get it"
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Burgess
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PostPosted: Sun May 03, 2015 8:59 pm
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At this stage keeping in a six-foot circle And being able to set it down in one piece is doing Really WELL!!

As you dial-in the heli and your hand/eye coordination improves the circle will begin to shrink smaller and smaller, a really good hover in no wind conditions, is heli static on station hands free...but that takes time...maybe next week Wink

Drifting to the left, RC helicopters do this when in close proximity to the ground, due to what's refereed to as ‘ground effect'. However, check the Aileron and Pitch servos for lost motion in the gear-trains; check that the servo arms are held fast to the servo output shaft; check the servo to swashplate link rod eyes for play too.



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