Trex 450 SE and general build videos are here

[razer t-rex]

Originally Posted by Charliedontsurf

After a 3 year hiatus, I got my trusty old, battered but rebuilt Trex450SE into the air this afternoon....Hovered 4 packs out with no crashes....Been doing lots with the sim and the CX2 and Mcpx in the house...Question....Why when doing my first ever piros with the 450, did the bird climb about 3-4 feet, and then when I made it snap to the left, it lost about 2-3 feet of altitude? Is there something I'm missing in the set-up, or was it nervous fingers on the collective increasing it or decreasing it? Got a 401 gyro and a mild normal pitch curve programmed (-3 -1.5 0 +5 +10 ) with a Finless Bob throttle curve in normal mode as well...
Any ideas?
Thanks!

it was probably because while spining you were increacing the headspeed so it lifted and if you went the other way it would probably drop

[harleymon]

Bob (Finless)

Thought I would say AWESOME JOB

You have done a wonderful job in helping me with heli setup - very well put together and easy to understand videos - thanks

Mike

[Charliedontsurf]

Hey gang, Rebuilding my Trex450SE, and following CCPM set up videos, can get zero pitch at mid stick, but pitch range is higher on the positive side (full stick), and 2 degrees less pitch at low stick...Which links would I adjust to remove positive pitch from the upper range and add negative pitch on the lower side...Right now it's +12 at high stick, zero at mid stick, and -10 at low stick...I have a linear pitch curve and swash miz is at 50% on a JR 9303 radio....Gonig crazy trying to get the mechanical set up correct...Have 3 new HS65MG servos all set at 90% at mid stick...Any ideas or suggestions would be appreciated.

Thanks!
Dr Franz in NJ

[Jasmine2501]

Originally Posted by Charliedontsurf

Hey gang, Rebuilding my Trex450SE, and following CCPM set up videos, can get zero pitch at mid stick, but pitch range is higher on the positive side (full stick), and 2 degrees less pitch at low stick...Which links would I adjust to remove positive pitch from the upper range and add negative pitch on the lower side...Right now it's +12 at high stick, zero at mid stick, and -10 at low stick...I have a linear pitch curve and swash miz is at 50% on a JR 9303 radio....Gonig crazy trying to get the mechanical set up correct...Have 3 new HS65MG servos all set at 90% at mid stick...Any ideas or suggestions would be appreciated.

Thanks!
Dr Franz in NJ

You will need to adjust all the links to fix this. Basically what's happening is the swash is riding too high through the whole range. SO, you have to reset the center - make zero pitch happen with the swash at a lower point on the shaft. You're going to have to tighten the servo-swash links and loosen the rest of them. Unless I have it backwards...

This is why I prefer the top-down setup method, detailed here...
http://jazzyflight.blogspot.com/2009...er-primer.html

[Dorantana]

Could you do a video detailing the replacement of the mainshaft and Feathering Spindle?
Both of these on my heli are bent and are in need of replacement. I have the parts, just not the knowledge or know how.
Thanks, Doran

[Jasmine2501]

For a Trex? There's lots of videos of that on YouTube, just try the obvious search terms and if you can't find anything let me know.

[Charliedontsurf]

Originally Posted by Jasmine2501

You will need to adjust all the links to fix this. Basically what's happening is the swash is riding too high through the whole range. SO, you have to reset the center - make zero pitch happen with the swash at a lower point on the shaft. You're going to have to tighten the servo-swash links and loosen the rest of them. Unless I have it backwards...

This is why I prefer the top-down setup method, detailed here...
http://jazzyflight.blogspot.com/2009...er-primer.html

Thanks Jasmine!
Very helpful and I'll set the 450 up again using this technique....I just had another mishap this morning- tail boom strike and feathering shaft...

Thanks again for the help!

Franz in NJ

[Charliedontsurf]

Originally Posted by Charliedontsurf

Thanks Jasmine!
Very helpful and I'll set the 450 up again using this technique....I just had another mishap this morning- tail boom strike and feathering shaft...

Thanks again for the help!

Franz in NJ

Jasmine,
2 quick questions.
What do you use to secure the blade grips of a Trex450/500 at zero pitch in the Top down set up technique?

Also, in the blogspot set up page, the gyro set up section, when checking gyro direction, shouldn't the tail slider move away from the tail movement? Finless Bob demonstrated this in his Gyro401 video, and it shows him moving the tail towards him (to the left) and the tailslider moves away from him. Do I have this correct, or am I confused by your description?

Thanks again for the info, it cleared up alot of set up confusion for me.

Franz in NJ

[Jasmine2501]

You want the tail blades to fight your motion. The tail moves in the direction of the leading edges. So, if you move the tail left, the leading edges of the tail blades should move to the right.

[65turbostang]

thanks for all the great vids&tich info. thought i was the worst flyer evevr but just not tuning my heli right . now ran 10 packs in her with no crashes.. finley starting to work on my fig8s not just trying to hover.....thank you!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[bjorgvin]

Does anyone add some glue or locktite on the tailboom before sliding the tail assembly on? Two times now the tail blades has forced the whole tail assembly 90` upwards. Resulting in a crazy piro. Last time it happend some of the screws in the tail assembly got pulled out. Resulting in damaged threads. Now I have ordered align parts to go on my hk450. Maybe I can tighten the hardware some more. And of course a bit of threadlock on the screw that secures the assembly on the boom. I can not remember if I did this last time..

[s0laris]

If its rotating easy try pinning it drill a small hole and use screw to pin it

[Jasmine2501]

Originally Posted by s0laris

If its rotating easy try pinning it drill a small hole and use screw to pin it

That's the best way but you can try a dab of CA glue on the main clamp but also a bit on the stabilizer holder.

[kgfly]

I found a layer of thin tape around the end of the boom usually did the job.

[harryw]

here is a big thank you uncle bob.i've could not done it without the videos.
or was it the vids that made me wanna build my own bird?
anyway a big smile on my face for days after first succesfull hovering.
all the best bob.

[facefirst]

Just like to post a huge thankyou to Finless Bob - I only got into this hobby last summer when I bought a HoneyBee V2 off ebay.

Decided to buy a CopterX 450 to learn about and build over the autumn/winter and the videos and knowledge I got from Bobs vids was second to none.
Also like to thank all you experts who post invaluable info and help to this site which has helped me fully understand everything from the radio setup to heli setup and tips n tricks.
I know I've built something that is solid, well setup and how to safely operate it.

And oh my god how different she is to The Bee - I've only done a couple test hovers for now as the weather is dodgy and I want to take it slow as I'm still a newbie flyer. Cant believe how smooth and stable it is compared to the Bee. The Bee requires quite a lot of continuous input, but the 450 I feel I could just let go of the sticks for several seconds.

[Gapruff1]

Thank you very much bob I've only just started watching your videos ,and they have helped me enormously thank you once again,please keep up the good work

[hopkin]

This is my first build , HK450 ,so I have been studying FB's videos closely and they have been a great aid .I've got to CCPM Pt 2 and now I'm stuck ! At centre stick the swash is level , flybar cage level etc.all fine until I try to level the mixing arm. I have got it level ,but the linkage arm is almost fully wound in ...This means to alter the pitch those links also need to be fully wound in ! If I lower the swash this will give extra adjustment to my linkage rods , but I then move even closer to the lockring AT centre stick I've a 4.5mm gap between the washout base and a 4mm gap at the swash ,so I could move it up but this makes the situation worse! I've measured the problem rods (without ends) and the're correct length. Servo rod and the rod to fly bar cage are set close to the dimensions given in the manual. At the moment it seems I have 2 choices ,set the mixer arm out of level or find a shorter link rod ,unless, of course I've missed something?

[lastofthefew]

Hi All

The blade balancing procedure outlined here in the 101 video ..will it work for 500 size carbon flybarless blades ?

i used it to the letter and when i spooled up bird it shook badly..and the swash began to self tilt ..without blades all is well ..

t-rex 500 pro using Tarot FBL head and 3gx gyro

[Häcksler]

Well, poo!

I just realized the videos are .wmv Windows friendly only files.

My Mac iPad, no likee.