Help me Build my New Heli

[Rogan]

Battery - Again, the market leaders are not hard to pick. For me it made more sense to get 3 cheap batteries for my learning phase than burning up the lifetime of 1 expensive one with performance I couldn't use. I have had good success with hextronik batteries from unitedhobbies.com. I have 3S 2200 12C/16C ones and so far (~150 cycles across 3 batteries) they are going strong. If I had to replace them today I would buy their new 3S 2200 20C/30Cs which at $32 are damn good value. If you want lighter weight they also have a 3S 1700 20C/30C which at $28 is even cheaper. Example: https://www.unitedhobbies.com/UNITEDHOBBIES/store/comersus_viewItem.asp?idProduct=2045


If you're using lower power batteries make sure you stay on a small pinion like 11T or they'll probably puff. Mine did - 13T on an AON 3500 - RIP. :(

[Jermo]

Ty sir, I'll look at that .

I'm staying excited!!! just picked up AGNM4365 Align 430L Motor 3550Kv and AGNE35G 35A BL Esc :)

slowly checking off the list.. motor and esc..check!
Jermo

[Jermo]

Question: Over time/repairs what parts do you suggest I buy metal upgrades for? Please list parts and order of imprtance.
jermo

[kgfly]

1) Reinforce the vertical stabiliser - DYI
As a beginner (and even now, but much less often) I was frequently tapping the tail on the ground. The stabilisers are very brittle and would simply snap. My solution was to reinforce the lower leading edge and bottom edge of the vertical stabiliser with some 0.6mm aluminium. This added a little bit of weight to the tail of course, but since then and despite some bangs and several crashes, I have not broken a vertical stabiliser.

2) Metal tail assembly
The plastic tail case is easily broken, I seemed to break mine in every crash. The metal tail assembly costs about he same as 3 plastic ones. After I bought my fourth plastic one I got sick of it and bought a metal one.

3) Full metal head
a) Buying the complete full metal head is cheaper than buying all the bits separately (or at least it was last time I looked).
b) You can buy a lot of plastic head replacement parts for the cost of the full metal head. The huge advantage of the metal head is that it is just so robust that it is very rare they get damaged. This saves a huge amount of time and fuss repairing and retuning the head. I have had four crashes with mine and each time, simply replaced the head on the new main shaft and flew the heli with at most a single tracking adjustment. With the plastic head I found several parts (and always at least one of the mixing arms) would break resulting in a almost complete teardown and rebuild of the head. That meant retuning the head each time.

3) If you cannot afford the full metal head then replace any of the following with metal when they break:

HS1056 Mixing arms
HS1081 Flybar frame (aka cage)
HS1197-72 Rotor housing set
(or piecemeal: HS1142-72 + HS1196-72 I think)
HS1207-72 Seesaw holder
HS1111 Swashplate
HS1201-72 Tail rotor parts (or piecemeal: HS1189-72 + HS1200 I think)

4) Some people like to leave the main blade holders as plastic so that they act as sacrificial parts. While I don't so long as you are running below 2800rpm that's probably OK. The metal blade holders are much more robust so save you the hassle of replacing one or both on every crash.

[Jermo]

Found this color scheme when I downloaded a rexxie for my sim.. thoughts?
http://www.mjsonsite.com/trex_color.gif

Jermo

[spork]

thoughts?

A bit to "festive" for my tastes. But that's why they make menus.

[kgfly]

Ummm,

That's not a TRex, for one thing it has a muffler :roll: I like them bright for good visibility. What sim was it for ?

[Jermo]

it was a download for the realflight 3.5 sim off their boards. The model was made by a user *shrug*. If I can find a better model of the trex w/o buying an expansion pack I'm definately getting it. Mostly looking at the color.

What would you guys suggest? my main concern is keeping the heli visable. I'll be painting it myself (probably take about a week or so from what I read). I'm an engineer so I'm not very artistic. )
Jermo

[kgfly]

jermo,

I am unsure what that heli in the picture you posted is, but it ain't a Trex. Not that it matters in terms of it being an idea for a canopy design.

There is a thread here on helifreak for TRex photos, check it out for lots of different styles and ideas. For me, high visibility is important, as is keeping the investment in the canopy to a minimum since it is sure to get destroyed. I actually made myself a high-vis training canopy from a PET soda bottle. It is incredibly tough, it even survived being run over!

It's a bit ugly and these days I prefer to fly with the nice canopy shown in my avatar, but sadly it doesn't look like that any more. It's mostly covered in clear packing tape to hold it together :oops:

[Jermo]

hehe...whatever works!! :) I really like the avitar somebody has with a shark on it. Reminds me of that shark cartoon char.

I agree about the time in the canopy. I've actually considered just leaving it stock with the decals but figured paint repair is part of the fun :) . It also helps me work on my artistic ability (or lack thereof :D ).
Jermo

[spork]

Kenneth, is that a little-boy heli, or a little girl heli? :mrgreen:

[Jermo]

Oh..and I was thinking without the flames since I'm artistically challenged..
jermo

[Jermo]

woot!
I think I am down to needing:
Tail servo
Lipo Batteries
Misc Tools
Spares

I'm ahead of schedule ;)

I can start assembly on the 25th of December!!
Jermo

[Jermo]

ok..Tail servo question.

HS56 was suggested because of my radio (non digital). If I'm not mistaken the Rx goes to the gyro (gy401) which feeds the tail servo. Wouldnt' the Gyro dictate the kind of servo? ie... 9650 instead of an hs56? I missed that in my re-read so I'm at odds... I do eventually plan to update my radio but it will be a while.

Jermo

[spork]

If I'm not mistaken the Rx goes to the gyro (gy401) which feeds the tail servo. Wouldnt' the Gyro dictate the kind of servo?

Yes, I believe it would.

[Pinecone]

At this time no radio is truely digital. So any servos will work with pretty much any radio.

The GY401 gyro does have a setting for digital tail servos, that mean that in that use a digital servo is desireable. But many people have and do fly with an analog tail servo.

And yes, the tail servo plugs into the gyro, which plugs into the Rx. The radio tells the gyro what you want the tail to do, and the gyro commands it. Sort of a fly by wire in full scale.

[Jermo]

ok...well the HS56 is much cheaper than the 9650. As a beginner will it matter? I'm still struggling to hover side in so it will be a while.
Jermo

[spork]

ok...well the HS56 is much cheaper than the 9650. As a beginner will it matter?

Nope.

[Jermo]

ok, Ebay has been good to me and folks here on Helifreaks are really helping me out in a major way (TY No_Gassers_Here, Microman, and Penrod for help with gear!).

I'll be working with:

1. T-Rex 450XL HDE Kit
2. DX6 (I broke down and got it since ebay stuff sold)
3. HS65MG x 3 main control servo's
4. F9650 x 1 for the tail
5. GY401 Gyro (with Ricks mount for under the boom)
6. 2100 20C 3s batteries from united hobbies (I'm a little uneasy about ordering from china but based on posts it should be ok).
7. X-Peak 3 Plus lipo charger (um..needs 12VDC PS..good thing I'm a ham and have
those laying around :D wonder what current it needs? mmm... 35A ought to be plenty :shock: ..hehe..I have a small 3A model from RS too..)
8. Deans (knock offs)
9. T-Rex carrying case (keeps my lovely bride happy to have my "toys" put up when not in use :wink: )
10. CA thin
11. Hobby Knife
12. Jewlers set
13. Velcro
<edit>
14. Align 35 5v ESC
15. Align 3550 Motor
</edit>


Items I think I still need:

1. Spares
[list:a71fde290c]
2 x 325 wood blades
2 x pkt of main shafts
2 x main gears
2 x pkt of feathering/spindle shafts
2 x pkt of blade grips
1 x outdoor first-aid kit

2. CA Thick
3. Paint
4. Thermal Epoxy (for ESC Fix/Mod)
5. Metal Vertical Stab
6. Metal tail pully (part number? I'll have to hit the drawing/manual if it's online)
7. Lipo alarm (I'll build mine from RS parts... I probably have most parts on hand..about $10 or less if I have to buy all parts).
8. working paper towels? Bob (Finless has them in his vids..I need to find out where they come from).
9. Heat sink for motor???
<edit>
10. Blue threadlock
11. Blade balancing tape
</edit>
[/list:u:a71fde290c]

Wish list:

1. Metal head


anything missing/wrong? rememeber I'm new (no official mentor either).


Jermo

[Pinecone]

Blue Loctite.

Also Fut S3154 is nice on the tail, at least so far. Micro digital servo.

For woodie blades, I really like the ones from Tech Model Products. $28 for 3 sets, our choice of 315, 325, 335 and colors (mix and match).

Of the last two sets I installed, one was spot on for CG and balance, the other set was a bit off, CG was maybe 1mm different between the two blades.

And I would say get more blades. I went through two sets in two flights. :( But it was flights 18 and 19 on my Trex.