HDX 450 Build Videos will be here

[BarnOwl]

Per, I think your problem might be the ESC. Try the ESC from one of your other birds and see what happens. I am not a big fan of the Otter, had a lot of problems with them. Don't use governor and look at the Otter setup Video (http://video.helifreak.com/?subpath=finless/hdxbuild&filename=otter_esc.wmv).

[broke-again]

My heli hit the ground like a house brick on steroids tonight...im gutted :(

I was only in the air about 30 seconds about 40' feet up when i gave some elevator for some nose up, to bring it back towards me tail in. Almost instantly it jerked and almost went vertical. Then started to drop back, following the tail at a high rate of speed. I gave some forward stick to level off - nothing! I did all i could to get some control, but by now it was useless. All i could do was kill throttle before impact and what an impact it was...it was like a whip cracking.

Damage was extensive and includes _ cleanly snapped feathering shaft, broken carbon fibre tail blade, main rotor carbon fibre blade, bent shaft, bent tail spindle,landing gear, flybar, tail control rod and busted canopy. The frame is intact, which surprised me. Tail servo and gyro all seem ok. pheww

On close inspection it would appear that my elevator servo may have failed just as it received a command. It was down and locked up. Im using HS56's

The serovs only have a few short flights on them, never had any buzzing etc. Does anyone know what would cause such a sudden failure? Also, apart from pre-flight motion/ response checks, is there any way to test a servo for potential problems?

I opened the serve up expecting to find broken gear - but none found.

Oh well, par for the course - but it stings!!!

Words of sympathy gratefully accepted.. :wink:

[TeamTEOR]

Sorry to hear it bro. I was warned last weekend by one of the heli guys to put HS65MG servos in there and never worry about it again. Another guy told me to get a larger tail servo as well. (after the kid goes to bed I will post what tail servo I have mounted up. If I leave the room he will follow).

I am at the point where as soon as it is in the air I will only let it go 5-6 feet in the air to learn how to hover, and basics first. I bet it is going to be way different than my Lama V3.

[Pinecone]

OK, here's the deal. I am currently flying a Blade CP. I am looking to move into a larger helicopter.

I was thinking of a Trex 450XL CDE with the HeliDirect frame and some upgraded swash plate. And over time upgrade it.

Then I read about the HDX. So my question to the experts here is which way go? Is the HDX worth the extra (which it really isn't a lot extra) over the XL for starting out?

I can get the Trex 450L CDE with 430L and 25A Algin ESC for $182, plus the frame kit and swash plate, or the HDX for $349, right now with the Otter ESC and 450 motor, both of which seem to be not the greatest.

Thanks for the help.

BTW has anyone tried the HD 877 digital servo? Looks like it would be a nice tail servo at a good bit less than the Futaba.

[backman8571]

Pinecone

The HDX 450 SE V2 is an assum heli.

I would go with the HD 577 instead of the 877.

Also use the HS56 or HS 65 servo's for the head.

Cheers

Per

[Pinecone]

I have HS56s, so that is fine. Thanks for the tip on the 577. The 877 was interesting due to the light weight.

I also noticed I can get a Trex 450SE CDE V2 on eBay for $370, with 430L motor and Align 35A ESC (without motor and ESC it is $340). How does that play into the decision between HDX and Trex 450XL and Trex 450SE?

Too many choices. :)

[backman8571]

I would still stick with the HDX 450 SE.

Just my view

Per

[BarnOwl]

I have HS56s, so that is fine. Thanks for the tip on the 577. The 877 was interesting due to the light weight.

I also noticed I can get a Trex 450SE CDE V2 on eBay for $370, with 430L motor and Align 35A ESC (without motor and ESC it is $340). How does that play into the decision between HDX and Trex 450XL and Trex 450SE?

Too many choices. :)

If you really can get a 450SE with 430L + 35a ESC for $ 370, I would definitely go for that. The HDX 450 is awesome, but the T-Rex 450 SE V2 is better cnc alu, real carbon fibre frame (Can also have disadvantages) and much more powerful motor/ESC combo. Just take care you get it from a reliable source. HeliDirect is very good in customer service, I wouldn't expect that from an Ebay auction.......

[leapfrog]

Hummm... just finished my HDX 450SE... and flew it today on it's maiden flights... took a bat or two to get it all trimmed out... and I must say... it flys *much* like my T-rex 450SE... actually, maybe even a bit *more* hands-off... it is a really stable bird, that does rock and roll when you let out the reins... I scared myself a bit when goofing off (and not watching closely enough - I was talking to another flyer) - but dang if it didn't recover through a bit of a low arch... but the 430L pulled it out nicely.

I bought the kit without the motor, and added: an Align 430L, an Align 35A ESC, and an Align RCE-500X gyro (sounds like an Align commerical, doesn't it)... like Bob, I mounted the gyro under the tail block - but I built a custom mount out of plexi, and secured it with double-sided tape and a velcro safety strap that passes through the mount and over the boom. I also trimmed the standoffs off the balls that mounted to the servo horns - as Bob suggested (I built a little jig to hold the ball straight and level as I dremel'd the standoffs down). The link throws are nice and straight... I *really* like the true 120° layout of the servo mounts on this bird.

Positives: head geometery, CG management, tail configuration (it's *all* metal with bearings), fit of the parts out of the box.

Negatives: no documentation, parts availability (but with the rex stuff, may not be an issue), canopy molding (there were thin parts I had to reenforce - and I did rather modify it to be more like the rex with a lower nose opening, and I opened the side ports for cooling), and the alignment of the main tail gear (I'm prolly gonna replace the main gear set with the Rex "finned" set anyway)...

All in all, I like this kit. The results, a nice stable - rather "fun flying" bird. It's got "oomf" with the 430L, and the blades were almost perfectly balanced out of the box (although I hate black blades - they disappear). Recommended kit - with Bob's build vids.

Who an I to recommend the kit? Nobody. Really. I'm an "average" heli flyer... I do fly daily, though... And I see fun in the near future with the MDX... that's all.

[a cook]

:glasses2:
Check out this micro heli,I am waiting on mine comming from the far east
but according to reports this is based on the t-rex comes with full metal head , gyro, servo's , 420 brushless motor , lipo battery etc looks the part.

[backman8571]

If you guy's like a neat heli look at HeliDirects new one the HDX450 FSE

http://www.helidirect.com/product_info.php?cPath=30_35_63&products_id=1530

Really good frame, battery cover, new look and plane cool.

Soon a new version, will be out that is the C frame, a mix of the SE frame and the HDX 400 and it is a belt drive like the HDX300 and 400 but in a 450 frame.

That is so cool

Per

[Finless]

FYI, I have both frames in hand and will be doing some vids on assembly of the frames only.

Bob

[broke-again]

Not sure what i think about the new frame - it's different thats for sure. From the pics it looks like the motor is inverted and id be worried about the way it and the servo's would be exposed if you did happen to crash.

[dutch_anykey]

Hey @ Broke again..

Crashed my hdx also again...remember that i wrote about my last crash...this is the 3 time in a row with the same behavier...also the spindle shaft snapped at 2 places right at the mainblade grips.. I was also bringing it down from a higher point (+/- 20 metres) And exactly the same problem again...slow spin of the tail, no control...Its getting me mad !!!! dont know what it is....striped servo gears again...i'm replacing the servo's now, i ordered the futaba digital servo and 3 hs65MG's hope they will arrive soon.
But it keeps me busy figuring out what the problem really is...Maybe someone can help ??...
The thing that i'm thinking of now.. each time one of the linkage rods connecting to the main blade grip (connection between mixer arm and main blade holder) is pulled into 2 peaces... could it be that the force on this thing when coming down fast is to big and snaps it in two peaces? (ofcourse its stupid from my side that i didnt check it after the first crash...i just screwed it together again and it looked fine....) I'm gonna order some new ones because i pulled it in to 2 peaces by hand, just to check how much force they could stand...offcoarse the trhead is worn out now...

Well at least i hope that someone can describe me from experience what the reaction of the heli is when one of the two linkage arm of the mainblade grip comes loose.....so no control over one blade....

thanks,

Maurice

[broke-again]

slow spin of the tail, no control

Whats your belt tension like? If it appears ok, check the belt drive system. Hold the tail blade grips and gently rotate the main rotor blades clockwise by hand. Apply gentle pressure only. You should feel the tail try to rotate instantly. If there is any slipage or play you will soon see / feel it. Other than that check the gyro function and all connections to your TX.

The feathering shafts will break under high impact, which in a way is a good thing as it stops the transfer of energy to the rest of the heli and thus reduces damage. I can Guarantee that your main shaft will be bent too - make sure you swap it and check the two main bearings, damage is often impossible to see on bearings, but if they are damaged you may hear a slight clicking as they are rotated.

I have no experience of how the heli would handle if the rotor linkages seperated, would suspect that they seperated due to the crash.

Keep your chin up and with every crash comes wisdom!

Good luck

[dutch_anykey]

Yep, its no tail control...so spinning very slow. and also going down...more collective doesnt seem to work when it happens....
strangly enough the main shaft is o.k....that was one of the first things that i checked after every crash. no bend in the mainshaft at all !! wich is pretty amazing because on my other heli's its practically the only thing you can be sure of.
tension of the belt is o.k. not slipping at all. pretty tight....

It's frustrating that it's crashing on its own....if it's going to crash i want it to be my fault !!! :bomb: at least during inverted or some other manouvre...not by going going down tail in :lol:

Thanks for the help, i'll keep you posted and update if i found the cause.

cheers,
Maurice

[Russ]

I had slow spin of the tail problem Turned out the brass fitting on the tail slider was coming out of the bearing. It was hard to find because by pressing the rudder to the right would cause it to slip back in but left stick would cause it to slip out again causing a slow spin.

[broke-again]

I had slow spin of the tail problem Turned out the brass fitting on the tail slider was coming out of the bearing. It was hard to find because by pressing the rudder to the right would cause it to slip back in but left stick would cause it to slip out again causing a slow spin.Assuming you did, how did you fix this problem Russ? Maybe you could tell us in case anyone else encounters the same thing.

Thanks

Bill

[dutch_anykey]

@Russ

Thanks for the tip!!! Will check it this evening.

I'm also curious about your solution.

best regards,
Maturice

[BarnOwl]

I changed the Sonix V2 tail that came with the kit while back for an Align alu SE tailcase. It is a lot better.

At the start of this thread you see pictures of my HDX tail blown apart. At that time I recieved a new tail from HeliDirect (Great service!) and at the same time I ordered a complete Align alu tail. I put both tails on two T-Rexes and flew them the same amount of packs.

The Sonix tail looks very impressive, but in the long turn Align wins clearly because of simpler design (less moving parts) and better alu. Especially the tailshaft is WAY harder than the HDX one.

Certainly worth the investment!

[Finless]

Same here.... Align tail due to parts availablility and it is more rugged. The longer shaft on the sonix tail is just too easily bent! If it is bent at all when you spool up expect the tail to explode.....

Bob

[dutch_anykey]

Hi guys,

Guess what.....i checked the tail unit...i was able to slide off the brass fitting by hand...not much force needed :arggg: Thanks for the tip Russ !!!! i really apriciate this :) You prabably saved me from some near future crashes :)
Suddenly i dont feel too well about that sonix tail....It hast cost me 3 crashes :bomb:

O.k. i realize its all part of the game...but something like this is not funny....
Better invest in the align tail unit...

thanks guys :hug:

[backman8571]

Bob.

What about that you create a fix it video for the tail????

Per

[BarnOwl]

There is another thing I found out about the tail GEAR unit: Several times now I experienced a bad vibration in the tail. After checking I saw the alu front pully (The part on top of the tail gear that drives the belt) wobbling heavily from side to side causing this vibration.
First I thought it was the shaft so I exchanged the whole tailgear unit, which is an incredible bastard of a job to to, because you have to take just about the whole after section of the frame apart.

Now this is the thing: It is NOT the shaft but the alu pully that bends!!!

Somehow this pully is hollow and just bends out of alignment with high rpm's.
Surely you can easily change the pully for another HDX alu one but the same will happen again in a short time. Actually when I put a new one on and spinned the thing up I already noticed some out of alignment!

So I took off a plastic Align tailpully and slided it on the shaft with a bit of CA. The thing is straight as a spear again, vibrations gone!

So an easy fix for this problem here.............

[Finless]

My HDX originally did not have the "slow down" gearing... I have since replaced the HDX tail drive shaft, little gear, and pulley to the Align one so I could use the lower align slowdown main gear. Works great and got rid of the pulley wobble as well.

Bob