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Old Mar 19, 2009, 04:45 PM
Yes I looped the MSR post 5388
EatAtJoes's Avatar
Joined Nov 2008
2,537 Posts
Quote:
Originally Posted by cruiser_kid
"HK-450 Goes Down In Maiden Test Flight! Government Cancels Contract. Rookie Test Pilot Survives, But Is Canned As Soon As He Hits The Ground."

Well, things didn't go quite as well as I'd hoped. The heli wouldn't lift off the ground without either going nose left or nose right almost immediately. I'm using the GY401B gyro (mounted underneath battery tray) and messed around with the gyro sensitivity settings in the radio a bit but it didn't seem to make a difference. One thing I noticed going through all of the pics on the thread was that some of you have the tail blades mounted with the thinner, curved edge facing forward, and some of you have the thicker (what I would consider "leading"), straight edge facing forward.

Now, I never thought to ask this on the forum, but I just assumed that my tail rotor should spin forward. However, looking closely at some of the videos, it appears that it actually spins backwards, which would explain the thinner curved edge facing forward since it would be the trailing edge in that case.

Anyway, long story short, on one of my hover attempts the training gear caught the ground and before I knew what was happening the heli had tipped over and basically disintegrated itself. Destroyed both main blades, the flybar, one flybar paddle, the pitch and aileron servos, both servo arms, main drive gear, feathering shaft, tail boom, and both tail rotors. It's a good thing I bought two of these helis!

I'm starting the rebuild process but thought I'd better confirm the direction of the tail rotor. Does it spin forwards or backwards, and which way should the blades be mounted? Also, if anyone has any good tips on starting point settings for the pots and switches on the GY401B those would be much appreciated. My tail servo is a Futaba S3154 so I've got the DS switch set to ON. I also just read that if using a digital servo, the DS pot should be set all the way to 0. Is that correct? What about the DR switch and the Limit pot? I'm using a DX7 radio and have no idea where to start with the Gyro Sensitivity Settings. What rates should I start with? What about the F. Mode settings?

I know, lots of stupid newbie questions and I should have asked them before attempting to fly the first time! ANY and ALL help/suggestions/advice here would be greatly appreciated. I've got one more shot at this before I have to start buying more stuff!

the tail rotor simply needs to come up into the wash of the main rotor blades, imagine the tail rotor blades being flat horizontally and picture the downdraft of the main rotor, you simply need to go opposite this down draft so your tail blades need to go up into that wash.

So from a stand point lets say you looking "from" the centre of the heli back towards the tail, then the tail rotation has to spin from the very back position (the furthest away point from you) then down to the ground then up towards you (the closest spot to you) then continue over the top till it reaches its start point again being furthest away from you.

The gyro sensativity on the Dx7 has to be from 51% to 100% this puts it into heading hold mode. start at around 72% and go up till you see tail was at hover then back it off little by little till it stops wagging.

Your pot your refering to is the travel range, Im a little confused with the question, basically the pot on the gyro is for the travel on your tail servo, this needs to be carefully adjusted, hmmm perhaps you need to look at BOB FINLESS's videos to see all the setup you need to do, also look at the Dx7 guide for trex 450....

let me know if you cant find those setup videos and I will see what I can do to assist
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Old Mar 19, 2009, 06:53 PM
Not a six pack
rocketscience's Avatar
USA, IL, Chicago
Joined Jul 2008
5,237 Posts
Quote:
Originally Posted by Hal_The_Hacker
i can post a pic if its any help or if you are interested?
Nah, I have since replaced the hxt900s with mg-14s and those DID just slide right in.

Thanks for the offer though.
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Old Mar 19, 2009, 07:06 PM
I Can Fly An FP Inverted!
Hal_The_Hacker's Avatar
Teddington, Middlesex, UK
Joined Jun 2008
1,536 Posts
just finished getting my heli ready for the maiden

these blades are SOOO unbalanced, three pieces of tape it took!!!

anyway, back to the point, can someone post their pitch and throttle curves please.
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Old Mar 19, 2009, 07:11 PM
I enjoy the voices
Lead Wings's Avatar
Perth, Australia
Joined Apr 2007
481 Posts
Quote:
Originally Posted by cruiser_kid
"HK-450 Goes Down In Maiden Test Flight! Government Cancels Contract. Rookie Test Pilot Survives, But Is Canned As Soon As He Hits The Ground."

I'm starting the rebuild process but thought I'd better confirm the direction of the tail rotor. Does it spin forwards or backwards, and which way should the blades be mounted? Also, if anyone has any good tips on starting point settings for the pots and switches on the GY401B those would be much appreciated. My tail servo is a Futaba S3154 so I've got the DS switch set to ON. I also just read that if using a digital servo, the DS pot should be set all the way to 0. Is that correct? What about the DR switch and the Limit pot? I'm using a DX7 radio and have no idea where to start with the Gyro Sensitivity Settings. What rates should I start with? What about the F. Mode settings?

I know, lots of stupid newbie questions and I should have asked them before attempting to fly the first time! ANY and ALL help/suggestions/advice here would be greatly appreciated. I've got one more shot at this before I have to start buying more stuff!
I can highly recommend the Lazy Susan method for getting your gyro sorted - it is much easier to fully test your gyro before you get into the air.

Lazy Susan's are pretty cheap (less than $10 if you hunt around - you don't need a fancy one - or steal from the kitchen).

Put the chopper on the Lazy Susan, then put some weights more than 3 kg/6 lb on the skids and make sure they can't come loose or the skid can't pop out, stand back then wind it up - if your gyro isn't working it will quickly show up. You can then easily play with gain etc, and can also test how well the heading hold is working, the left/right control and how quickly it stops and holds.

Just make sure you have throttle hold on or disconnect the battery if you are goig to tinker with the manual gain on the gyro. Also disconnect the battery and re-connect if you make any major changes so the gyro re-initialises.

It won't be exactly the same as in the air, but better to find if you have a problem before you get that gravity thing too involved and find you have a problem - and a heli trying to destroy itself at the same time!
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Old Mar 19, 2009, 09:13 PM
Registered User
Joined Sep 2007
666 Posts
Quote:
Originally Posted by Hal_The_Hacker
just finished getting my heli ready for the maiden

these blades are SOOO unbalanced, three pieces of tape it took!!!

anyway, back to the point, can someone post their pitch and throttle curves please.
Just use the ones from the Trex SA manual from Helifreak. These worked for me out of the box.

I know what you mean about the main blades, I ordered two kits one they were fine. The other had two different tips on the blades and was 5mm shorter than the other one. Im waiting for a response back from HC on a replacement set.

Cheers
Brett
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Old Mar 19, 2009, 09:26 PM
Registered User
mhills51's Avatar
kansas city
Joined Feb 2007
11,882 Posts
Quote:
Originally Posted by Lead Wings
I can highly recommend the Lazy Susan method for getting your gyro sorted - it is much easier to fully test your gyro before you get into the air.

Lazy Susan's are pretty cheap (less than $10 if you hunt around - you don't need a fancy one - or steal from the kitchen).

Put the chopper on the Lazy Susan, then put some weights more than 3 kg/6 lb on the skids and make sure they can't come loose or the skid can't pop out, stand back then wind it up - if your gyro isn't working it will quickly show up. You can then easily play with gain etc, and can also test how well the heading hold is working, the left/right control and how quickly it stops and holds.

Just make sure you have throttle hold on or disconnect the battery if you are goig to tinker with the manual gain on the gyro. Also disconnect the battery and re-connect if you make any major changes so the gyro re-initialises.

It won't be exactly the same as in the air, but better to find if you have a problem before you get that gravity thing too involved and find you have a problem - and a heli trying to destroy itself at the same time!


If both heads are setup correctly (yours and the heli) as long as you don't panic you can set the heli right down with no problems. I have three time taken off with everything reverse with out a any problems. But for the guys without the heads set that is a good idea.
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Old Mar 19, 2009, 10:59 PM
Barnwell, SC
Barnwell, SC
Joined Sep 2004
834 Posts
my HK450#2

I finished #2 tonight and did two batteries under the porch light to set the trims and gyro. Ready to rock and roll tomorrow. I call this my hk-align hybrid since it has some Align stuff in it. It has the tail drive set, metal motor mount, Align 430L motor and 35G esc, SA canopy and Align 325 woodies. Running a Telebee gyro, HXT900 cyclic servos, E-Flite 7.5g digital heli servo on the tail and Spektrum DX6i with AR6100. This kit had better screws but the blades had different tips and I was missing the canopy grommets. Even at that, I consider this kit a tremendous value.
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Last edited by hfenn; Mar 19, 2009 at 11:30 PM.
Old Mar 19, 2009, 11:32 PM
Barnwell, SC
Barnwell, SC
Joined Sep 2004
834 Posts
my 450 fleet

I have from r-l a Trex SA, SE, HK w Align stuff and an HK on the cheap. I'm luvin the 450's. Been doing loops, flips, rolls and nose-in and now want to tackle inverted. I think I have some back-up now!
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Old Mar 20, 2009, 02:38 AM
Registered User
Maryborough, Australia
Joined Dec 2007
170 Posts
Just finished putting mine together. Spun it up in the shed and hovered beautifully. Blades track with no problems at all. I might take the blades off and balance them though as i was in a hurry to see if it would fly
Might have to order another or 2 i think.
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Old Mar 20, 2009, 06:38 AM
Registered User
baltimore, md
Joined Dec 2008
453 Posts
Quote:
Originally Posted by hfenn
I have from r-l a Trex SA, SE, HK w Align stuff and an HK on the cheap. I'm luvin the 450's. Been doing loops, flips, rolls and nose-in and now want to tackle inverted. I think I have some back-up now!
nice squadron you have there. I bought 2 HK's myself, but only 1 is flying and the other has been robbed for parts. the 2nd HK will fly as I have the copterX head that I can put in it.
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Old Mar 20, 2009, 09:11 AM
Registered User
Strathmore, Alberta Canada
Joined Jan 2004
848 Posts
parts

hi all I just ordered this and the motors recomended are back ordered can anyone recomend another . the turnigy and the hk motors are the ones i'm talking about

as well the recomended tailservo is no longer available the 2216 servo i think it was

any help on the motor selection would be great
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Old Mar 20, 2009, 10:27 AM
Registered User
skunkworks2006's Avatar
Michigan
Joined Nov 2006
2,712 Posts
It seems that someone at HC did not expect so many kits being sold to equate with lots of parts being sold.
Inventory of many of the parts is in the negative. I hope they get new stock in soon. I'm just glad that T-rex parts are compatible even if they do cost more.
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Old Mar 20, 2009, 10:45 AM
Not a six pack
rocketscience's Avatar
USA, IL, Chicago
Joined Jul 2008
5,237 Posts
Quote:
Originally Posted by nickrage
hi all I just ordered this and the motors recomended are back ordered can anyone recomend another . the turnigy and the hk motors are the ones i'm talking about

as well the recomended tailservo is no longer available the 2216 servo i think it was

any help on the motor selection would be great
A friend is in the same situation. helidirect has some budget motors in the HDX section. 1 of them (3550kV) has mostly positive reviews so that might be a good choice.
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Old Mar 20, 2009, 10:54 AM
I Can Fly An FP Inverted!
Hal_The_Hacker's Avatar
Teddington, Middlesex, UK
Joined Jun 2008
1,536 Posts
I was finishing setting up my heli last night (balancing blades, checking throws etc.) and i checked the belt tension, it was as per the t rex manual when i pulled out the boom, and so i tightened it as so, then i did the 'belt slippage test', you hold the head still and twist the tail till the belt slips, judging by the amount of force it takes determines if your belt is tight enough.

well, long story short - the damned gear slipped on me, before even an initial spool up, man am i PISSED.

i had to tear the lower half of the frame off to get to the damned thing, i did the ol loctite trick, except i used a file to roughen the shaft because i dont own a dremel.

waiting for it to set, time /belt tension test will see how it holds up.

does anyone know an actual figure for blue loctite to set? i loctited it at about 1am this morning (GMT), wondering if it will be set by around 7pm or so....
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Old Mar 20, 2009, 11:39 AM
Registered User
Joined Nov 2008
313 Posts
Quote:
Originally Posted by Hal_The_Hacker
I was finishing setting up my heli last night (balancing blades, checking throws etc.) and i checked the belt tension, it was as per the t rex manual when i pulled out the boom, and so i tightened it as so, then i did the 'belt slippage test', you hold the head still and twist the tail till the belt slips, judging by the amount of force it takes determines if your belt is tight enough.

well, long story short - the damned gear slipped on me, before even an initial spool up, man am i PISSED.

i had to tear the lower half of the frame off to get to the damned thing, i did the ol loctite trick, except i used a file to roughen the shaft because i dont own a dremel.

waiting for it to set, time /belt tension test will see how it holds up.

does anyone know an actual figure for blue loctite to set? i loctited it at about 1am this morning (GMT), wondering if it will be set by around 7pm or so....
I would wait 24 hours. No point in risking further damage.
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