HK 500 TT FBL - Any Good?

[HunkaJunk]

So a buddy of mine gave me a brand new HK 500 TT FBL helicopter, only needs a motor, esc and RX. He has a few of them and was using them for practice, presumably because they were so cheap, he doesn't think much of the HK helicopters.

On inspection, I have a couple concerns:

The main gears seem very soft and flexible. It's going to need some work here because there is a tight spot in the gear train without tail boom even installed yet. It's going to be noisy

Driven tail gear did not line up with main drive gear. I was able to disassemble the tail drive assembly and move the gear on the shaft to make it line up with the drive gear fully.

The main blades it came with are horribly balanced.

It has a ZYX flybar-less unit, and I got the interface with it. are these any good? There seems to be some people having good luck with them on, I was intrigued by the ability to use just a single Spektrum satellite RX.

At this point I think I'm going to use this helicopter as a FBL learner, I'm reluctant to invest a lot of time or $$ into it based on the overall quality of the thing.

[Abenn]

A while back I bought an HK 500 TT flybarred. I'd heard about tail issues so, before I flew it, I installed a complete Align tail unit which I had as a spare for my T-Rex. Then I tried to test-fly it, but the vibration was so bad that I gave up after 10 seconds. The blades had been carefully balanced, so I think the vibration was a combination of poor bearings, maybe out-of-round main gear, and other poor tolerances.

So, in went a spare head unit, main shaft and bearings, and main gears that I also had as spares, and it's been flying great ever since The main thing is I haven't touched the torque tube or its gear sets, and I haven't noticed any issues there.

[DCflyer]

Originally Posted by HunkaJunk

So a buddy of mine gave me a brand new HK 500 TT FBL helicopter, only needs a motor, esc and RX. He has a few of them and was using them for practice, presumably because they were so cheap, he doesn't think much of the HK helicopters.

On inspection, I have a couple concerns:

The main gears seem very soft and flexible. It's going to need some work here because there is a tight spot in the gear train without tail boom even installed yet. It's going to be noisy

Driven tail gear did not line up with main drive gear. I was able to disassemble the tail drive assembly and move the gear on the shaft to make it line up with the drive gear fully.

The main blades it came with are horribly balanced.

It has a ZYX flybar-less unit, and I got the interface with it. are these any good? There seems to be some people having good luck with them on, I was intrigued by the ability to use just a single Spektrum satellite RX.

At this point I think I'm going to use this helicopter as a FBL learner, I'm reluctant to invest a lot of time or $$ into it based on the overall quality of the thing.

Your observations and general attitude toward that machine are spot on. It is a cheap heli. There is lots of things that are considered sub-par on it. The head and tail assemblies are usually not very well machined and therefore not balanced and people replace those with Align units.....especially the tail. You may get lucky and not need to. A test spool with no blades will show major vibrations if they are no good.

The bearings in these heli's are also quite bad. They must be ABEC 1 bearings because they need replacing very early on. In fact, since the heli is currently stripped down from what I understand, it may be a good time to replace the bearings in the major assemblies such as the mainshaft, torque tube, grip bearings etc. Its very easy to do and not very expensive.

The ZXY FBL is certainly capable. There is a dedicated support forum for it here so you can learn more there. I wouldn't invest for another FBL in such a machine. An Align 500mx motor, decent ESC like Castle or YEP, and the ZXY should make for a good trainer.

Just make sure the airframe is up to snuff before you go buttoning up the heli fully.

And get yourself a quality set of main and tail blades. Good blades make all the difference in a smooth running machine. A set of Zeal's should do the trick. They should be very well balanced out of the box (may need a piece of tape just to make them perfect, but that's it).

You can't argue with a free airframe. Get it flying and don't worry too much about putting the best parts in it. It will fly pretty much the same. Just make sure to do a series of test spool ups with no blades at various headspeeds to make sure there is no ill tendancies or bad vibrations, etc. Should be good to go.

[Gladius]

The ZYX works just fine. I've had one on my 500 for about a year and a half, and never had any issues with it. The FBL Systems forum has a sticky on setting one up.

If you want to replace your head and tail unit for cheap, try using Tarot parts. Quality is on par with Align, but you can usually get them for cheaper.

[HunkaJunk]

I picked up a used E-Flight ESC from a Blade 500 at the LHS, got a Blade 500 motor coming because it was less expensive, bought a RX, 2800 mAh 6S battery, and I also replaced the main and autorotation gear with Align gears, that seems to have taken care of the tight spot and blatant noise in the gear train.

[HunkaJunk]

Well, after replacing several parts while chasing some pretty obnoxious vibrations, I think I finally have a good flyable helicopter, it took some more parts to get it where I consider it flyable, it's smooth as silk now.

1) As posted above, the main gears were replaced with Align gears, I used the helical cut main gear, with a 13T pinion.

2) The TT tail gears were of inferior quality, causing severe vibrations. tail gears were replaced with Align parts.

3) The TT drive gears were also no good, causing tooth skipping and finally sheared a couple teeth off during a slow spool up. Also replaced with Align parts.

4) I was unable to track the main blades properly until I noticed that the finish was de-laminating on one of the main blades. I put a set of Edge blades on it and the problem was instantly fixed, proving that I had a sound setup. I'm guessing that this HK blade was damaged in shipping at come point, or just a poorly made blade.


I'm running the head at 2500 in NORM and 2650 in STNT1 and STNT2, it's smooth as silk and sounds fantastic with the Edge blades on it. my ESC does not have a governor, but it should be fine for now, seeing how I'm not a big 3D pilot.

I did some hovering and made some minor trim adjustments, it was pretty windy today so I'm pleased with it so far.