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Nov 24, 2008, 12:40 PM
1.21 Gigawatts!
Steph280's Avatar
Thread OP
I think the mushy tail issue they talk about on HF was the servo travel not going to the max due to some setup issue? Not sure, didn't read all of the posts.

Anyway the tail on 250 is really sensitive to your collective pitch range. Ideally you want -10/+10 and maximum -11/+11. Any more than that the tail will lose holding power and give. I keep my max pitch at -+10 and tail is holding fine. I posted my settings on HF:
- gyro gain 35% AVCS mode on 14MZ
- servo ball distance 7mm. I plan to move it to inner most hole at 5mm and increase gain.
- 750 settings : 1520us, DS, Rev, Limit set with no binding, Small heli, 0 delay
- which gyro tape: stock
- c/f tail rod or not: stock metal rod

And to avoid the static issue on the old 500, I also sprayed my belt with WD40.

John, that antenna looks awfully close to motor/ESC. try relocating to the rear end of heli.
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Nov 24, 2008, 12:42 PM
1.21 Gigawatts!
Steph280's Avatar
Thread OP
Quote:
Originally Posted by RCBABBEL
Excellent review work Steph280!

What shops have these in stock?

Who do you guys buy from in the US?

Thanks,

rc
They seem to be in short supply right now. Look around on the popular online vendors, or place a pre-order with them. They get snatched up pretty fast.
Nov 24, 2008, 10:43 PM
I'm just a 2.5D Pilot
rickgode's Avatar
Steph280, what do you (or anybody for that matter) use when you have screws that go into plastic?

Ricky
Nov 24, 2008, 11:49 PM
1.21 Gigawatts!
Steph280's Avatar
Thread OP
You mean as far as thread locking compound? or tool used?

You could use a drop of CA, but it will be difficult to remove in case repair is needed. I don't use anything for self tapping screws. Just make sure you don't over tighten it. These screws are tiny and soft, they can easily strip if too much force is applied.
Nov 25, 2008, 01:27 AM
I'm just a 2.5D Pilot
rickgode's Avatar
Thank you. Yes, I meant thread locking compound. I love the intricacies. So far I"m having a blast just taking everything apart and putting it back together with loctite. So far, everything already had it.

Now here goes a stupid question, forgive me if my terminology isn't correct. Do you glue/loctite/red stuff bearings to the shafts that go through them? Or is just a press on fit?

I was playing with my little MCX which had a couple of bearings that the main shaft went through, I lubed them up and also put lube on the shaft as I was inserting it through the bearings, then I remembered something I Read in the TREX 250 instruction manual about using the R48 (red stuff) on bearings. At first I thought, "huh, I thought bearings were supposed to move" Even on my Brushless Blade CX , I lubed the inside of the bearings where the shafts went through. Am I not supposed to be doing this? Is it a bad habit?

I'm sorry if these have been answered before, but I have never built anything that had so many bearings and moving parts before.

Thank you.

Ricky
Nov 25, 2008, 10:40 AM
1.21 Gigawatts!
Steph280's Avatar
Thread OP
The idea of applying loctite inside the bearing is to prevent the inner race from spinning freely. It should remain stationary with the shaft/axle so the bearing outer race is the only thing that's turning.

While it's ideal to apply loctite to every single bearing's inner race, in reality it's difficult to do in a small heli like this. And amongst all the helis I've had, only one had the bearing inner race spin and cut a grove onto the main shaft, but that was a 22cc gasser with tons of vibration. So it's probably not needed.

But if you absolutely want to put some loctite on the inner bearing race, I would focus on 2 spots: the two main shaft support bearings, and the two tail shaft support bearings. Use a needle to apply the loctite and be very careful not to get any into the bearing itself.
Nov 25, 2008, 10:44 AM
Plastic Buddha
aftica's Avatar
...
Last edited by aftica; Apr 23, 2009 at 08:31 AM.
Nov 25, 2008, 11:42 AM
Put a Quark in it!
nexgen's Avatar
This is just a thought, you may have already tried this.

Try to up the headspeed. More headspeed=more tailspeed=more tail authority. Also you wont need as much pitch with higher headspeeds so climbouts wont require as much torque taht the tail would have to counteract.
Nov 25, 2008, 11:55 AM
Heli Hooligan
Quote:
Originally Posted by aftica
the tail is not reliable though. it is mushy...no authority, wags gently to and fro whilst hovering, and won't hold on a punch out. i have tried EVERYTHING on the various forums to no avail. it is flyable, but no better than the B/L blade cp/cp pro that it replaces in my fleet.
Waggy tails are a problem that can occur on any heli and can be caused by a number of things, including...

1. Binding in the tail mechanics. Check the pitch slider and blade grips all move smoothly.

2. Too long a servo arm. Try a hole further in and see if it helps.

3. Gyro/tail servo wires bunched together with ESC wires. Run the gyro and tail servo wires along a seperate path away from the ESC wires.

4. Dodgy bearins can emit RFI. It could be the motor bearings too. Listen for a high pitched pinging sound.

5. Static hits from the belt. Some silicone oil on the belt might help. Jason Krause claimed to use WD40 in one of his videos.

6. Faulty Rx. Yes, I had a wagging tail problem on one of my helis and it turned out to be a faulty AR6100. I proved it by swapping in another AR6100 from another heli.

With 3 to 6 the tell tale signs are the servo twitching. Take the blades off and spool up with the heli clamped down. Hold the boom still and if the tail servo twitches then the problem could be one of 3 to 6.
Nov 25, 2008, 12:20 PM
Plastic Buddha
aftica's Avatar
...
Last edited by aftica; Apr 23, 2009 at 08:32 AM.
Nov 25, 2008, 12:45 PM
Registered User
ForceFedDSM's Avatar
Quote:
Originally Posted by aftica
thanks guys. but like i said...i've tried it all, and more! i have owned and set-up many, many helis and this is the only one given me any real grief.

the tail mechanics are sloppy on this heli, and i know that is a problem... just can't figure out how the pros have overcome this, as i am assuming they are all the same kits?

head speed does sound a little low compared to teh vids, so that must be the bigger pinion (16T) they have access to... as again i assume the motors and esc's are all the same.

so i'm waiting on a bigger pinion, a fix for the sloppy tail section, or one of the factory guys to let loose on the ''secret''
Over on HF some of the owners are finding that the tail blade holders feel fine at rest, but when they disassemble them, they find the bearings are loaded with loc-tite. Remove the bearings and check them, if they have loctite in them clean and resuse or replace if you can get spares. Try that out and see how you make out. My kit came in today and I plan on checking them before I leave the store.

Jared
Nov 25, 2008, 01:17 PM
Plastic Buddha
aftica's Avatar
...
Last edited by aftica; Apr 23, 2009 at 08:32 AM.
Nov 25, 2008, 01:22 PM
1.21 Gigawatts!
Steph280's Avatar
Thread OP
Have you reprogrammed your ESC? If you are not getting the headspeed you want, it may be that the ESC throttle curve is not hitting the top with your radio. Every radio has different throttle travel range.

I run my throttle (non-governor) at 90%. Small heli like these need high headspeed to have enough tail authority. Wondering tail just seems to be a sign that it's not getting enough power (RPM) at the tail. After about a dozen or so flights, my tail is not any more sloppy than any other Align heli. So you might want to look into what's lose and try to correct it.
Nov 25, 2008, 02:08 PM
Put a Quark in it!
nexgen's Avatar
aftica, what is your pitch range? too much pitch (perhapse to compensate for not enoug g headspeed) will cause too much torwue, and the tail will kick out on pumps. Enough headspeed and you shouldn't really need more than +-10, and the tail will have more authority.
Nov 25, 2008, 02:50 PM
On RCG Vacation - Part 107
blade strike's Avatar
Brotha aftica -


I could really start posting some quotes that you made regarding other heli's that you were bashing on but I think I will pass

Oh well we are all in the same boat, there are some issues with the tail, Simple as that!!!
Last edited by blade strike; Nov 25, 2008 at 02:58 PM.


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