HDX 450 Build Videos will be here

[Essie]

Hi everyone,
Trex 450 SE.
can anybody please give me some advice on how to secure the tailcase to the tailboom. The idea of one little screw being in charge of the tailcase frightens me somehow.

On my 450XL the tailcase has that protrosion where the tailboom's hole must fit in. Apparantly this is not the case for the SE.
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http://www.helifreak.com/album_mod/upload/d37ef654dd2678cfce5fe2f72f6a87ec.jpg
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http://www.helifreak.com/album_mod/upload/77c7ecc838df5f7c1552defa9168d351.jpg
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http://www.helifreak.com/album_mod/upload/78c34a8c45000a737eab6224ad915fb0.jpg
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Thanks-Essie

[leapfrog]

Hey Essie... yep, you're correct. Just the one screw pinches the tailcase to the boom. Most wrap a single wrap of lightweight tape to the boom to give the tailcase a bit more bite. I didn't and it holds just fine (well except for that one really spectacular tail-first impact... but that's another story).

[BarnOwl]

After months of flying with the HDX Sonix head the control levers that connect to the swashplate becomes really sloppy after a while and you cannot change the bottom arms as you can by Align. They might be alu, instead of the plastic arms from Align, but the pins that hold them wear out and cause an immense amount of play in the up- and downward control of the swash.

Furthermore the Sonix (HDX) swash threads holding the balls is in my case worn out.

My conclusion on the HDX/SonixV2 alu: It looks great and it is a bit cheaper but Align CNC alu is a LOT better quality.

Finally I ended up with a complete Align Alu heli except for the frame.

Another thing is the HDX booms: The booms I recieved from Helidirect (Carbon as well as alu) all have a slightly smaller diameter then the Align booms. In my case all HDX booms could NOT be tightened properly and I needed tape to make them solid.
The Align booms are a much better fit.

In the end my conclusion is that IF you are considering to save a few bucks and get the HDX 450 instead of the T-Rex 450 SE I would get the T-Rex now. The HDX is a very good value but the Sonix parts don't live up the expectations because I found out the Sonix alu is just weaker than the Align alu.

[Essie]

Thanks, I will sure try the tape.

I've seen some guys put a machine screw right through the whole casing and boom with a lock nut on the the other side, but the tailbelt eventually DOES touch that screw and wears down the belt FAST. Not the route I will go.

I find it difficult to believe that it is the best Align could come up with, considering the rest of the heli. I've written of a few helis and most (if not all) of them was pilot error. But then I have seen the number 3 in our country totalling his SE and I have a sneaky idea that the tailrotor casing rotated in midair.

[BarnOwl]

Essie: To avoid confusion would you please post your questions about the ALign T-Rex SE in the Align 450 forum?

It is already confusing for a lot of people what the difference is between 450 SE/HDX 450 SE. This is the HDX 450 SE forum......... :wink:

[Essie]

Thanks BarnOwl, will do so. Just one Q, where exactly is the 450 SE forum? I cannot find it...

[leapfrog]

Hey BarnOwl...

I've just about completed the head re-work on my HDX... all new stainless, and the links are an Align set that I've spent about an hour on sizing... each now fits very well to it's respective ball. No play, and very free. I swear, the head all seems much more free in general now. I checked that washout linkage, and there is some looseness on mine... but not too bad.

How many flights do you have on your bird?

[leapfrog]

Essie,

Here is the tech forum (http://www.helifreak.com/viewtopic.php?t=12455) for the Rexes - including the SE...

[Russ]

I agree with Barnowl. I have replaced most of the cheap HDX parts with Align parts. the sonix tail came apart on me shortly after I got the heli. I too have had head issues. The bearings did not fit into the bearing blocks on the tail drive unit and the lower main gear was warped. None of which Helidirect did anthing about. And now its $10 buck for 3 tail shafts. The money I have spent replacing parts on the HDX 450 would more than cover a Trex se.

[BarnOwl]

Thanks BarnOwl, will do so. Just one Q, where exactly is the 450 SE forum? I cannot find it...

Except for the Finless tech forum most common questions for the T-Rex 450 are answered in the Align electric 450 forum:

http://www.helifreak.com/viewforum.php?f=77

[Helibum]

Hey Barnowl i'm a little confused did you buy a HDX450 complete Heli or did you just buy the aluminum HDX parts for your TREX cause thats what it kinda sounds like.


Jim. :glasses2:

[Helibum]

Hey Bob have you gotten the compatability list from Steve yet I also would like to know which parts will fit.

[Russ]

Hey Helibum just noticed your from Tampa. I'm right next door in O-Town.

[BarnOwl]

How many flights do you have on your bird?
I didn't count them, over a hundred I guess.......


Hey Barnowl i'm a little confused did you buy a HDX450 complete Heli or did you just buy the aluminum HDX parts for your TREX cause thats what it kinda sounds like.
Jim. :glasses2:

I bought the whole HDX 450 SE set.

[ps61785]

The motor shaft dia is different on the HDX300 (2.3mm) HDX450 (3.17). Measure with calipers to see what you have. As for Kv ratings, i understand that the KV rating is how many revolutions the motor will produce per volt applied. E.g a 3800kv motor - 11.1v battery = 3800x11.1=4,218 rpm (no load-zero pitch) Compared to the HDX450 3000kvX11.1=3,330 Rpm


The RPM figures are really 3000*11.1=33300RPM and 3800*11.1=42180RPM. Just thought that i would post a correction.

[ps61785]

Barnowl,

I have an HDX450 but the head seems to be fine. The wash out linkages seem to be all ball bearing supported where needed. Did helidirect possibly change the head that they are using to build these Helis. I am having no problems with the arms for the wash out base. Can yoy tell me exactly where you noticed the problem. Thanks.

[Helibum]

Yes that was going to be my next question. Hey Barnowl can you post some pics of the problem areas, i'm not exactly sure which parts you are talking about. Thanks


Russ I noticed we are close to, small world maybe we can get together sometime and go flying.

Broke Again, thanks for the info on the batteries just purchased two batteries and a charger from the guy also got the balancer to all for $130 allthough I did not read your post all the way threw before I went there I may have been able to get the stuff a little cheaper oh well I still am happy with the deal. Thanks again.


Jim :glasses2:

[BarnOwl]

I am sorry about the confusion, the slop is in the metal pin connecting the two parts of the control lever as shown in the circel on the picture. I had about 5mm sideways movement on the bottom resulting in unresponsive pitch control.
Hope this makes it clear.......

[ps61785]

I am sorry about the confusion, the slop is in the metal pin connecting the two parts of the control lever as shown in the circel on the picture. I had about 5mm sideways movement on the bottom resulting in unresponsive pitch control.
Hope this makes it clear.......


They must have changed the head that they use or changed the design of it because my head has a screw instead of the pin and a bearing for the arm attached to the washout base where the screw goes through it. My swash is also different. Also, I have a full blue swash plate. It appears that the one above has a part that is silver or black.

[Russ]

Russ I noticed we are close to, small world maybe we can get together sometime and go flying.

Sounds good Helibum let me know when.

[Russ]

PS61785 wrote

The RPM figures are really 3000*11.1=33300RPM and 3800*11.1=42180RPM. Just thought that i would post a correction.

I think those numbers are a little high. Given a 3000kv motor,11.1v battery and a 11t pinion and 150T main gear and an efficiency rating of 80% the Rpm's should be around 2200. The 3800kv given the same parameters should be around 2600. With a 13t pinion it would be a round 2500 and 3200 respectively, I think.

[ps61785]

Oh they were quoting headspeed and not Motor speed. I miss understood that part. Yes those figures seem to be correct. Sorry for the confusion.

[leapfrog]

Yep... looks like I have a later head from that one too, BarnOwl (same as ps61785)... mine has a screw in it also... and the play is 1.22mm at the link end (laterally) on one side, and 0.93mm on the other side - with 77 flights on it.

Here is my head... notice the screw (http://www.helifreak.com/album_showpage.php?pic_id=13118)

Seems to me that they are working the "issues" out of this bird... the later versions seem to be addressing the issues... not good for the early birds, though... I'm planning on the maiden flight tomorrow after replacing the aluminum balls with the stainless, and new links all resized (getting some of the stock balls off was an "adventure" in itself) - and I removed the "useless" ball on the front of the swash... I thought of screwing something fun in it's place, but I guess I didn't have the energy after all the work.

[BarnOwl]

Ok, that's good to hear, I got one of the first sets, so if they are improved, all the better.........

[Helibum]

Hey Finless any idea when you may get the list from Steve. The compatability list that is between the Trex and HDX450SE. Thanks and great videos by the way!


Jim. :glasses2: