HKH-500 build thread

Could not resist the temptation to start building my HKH-500.
To increase the joy of building this baby, I will do a build thread.

I bought the HKH-500 from ebay. It is identical to the HK-T500 except for the canopy, which is a nicely painted fibre glass canopy in my kit.

What's in the box




Bytheway, HK did release a new version of this kit with a full metal head, but the tail unit is still plastic.

From the start I will upgrade this kit with a full metal head and tail, metal main shaft holders, Align main shaft and glass fiber rudder servo mount.

As a metal head and tail upgrade I bought this from Ebay.



Browsing through the HK forum I feel the need to upgrade the main shaft holders to metal. These can be purchased from HK, spare part from new HK-500GT kit.



The main shaft that comes with the kit is made from aluminium. Don’t now what the main shaft is like that comes with the metal head and tail. But to be on the safe side, I've ordered a set of main shafts from Align. (Though the spare main shafts at HK look like steel judging from the pictures, buyers report them to be made of aluminium. So be careful.)

And the last upgrade (for now ) will be the rudder servo mount. This is made of metal. I’ve found several reports of this piece breaking. I could have gone with the HK fibre glass rudder servo mount of the HK-500GT. But instead, I decided to go with the rudder servo mount of the Align T-rex 600 (also fiber glass). This allows me to use a standard sized servo, which means more torque at a better price!

Just got an e-mail this morning that my first order from HK is on its way

Here is what I've bought so far:

For cyclic I will use these servo's, GWS Park HPX Servo 19g/.05sec/3.6kg.



The motor is gonna be the Hobby King 500H Heli Motor 1600kv (500 Class).



Before, I considered using the Turnigy 1800kv motor, which seems to be a very (if not TOO) powerfull motor. But reports of this motor running hot, high Amp usage and balistic head speeds threw me off. Maybe at a later stage I will give it a go.


The receiver (Spectrum AR6200), servo's and gyro will be powered by this TURNIGY 5-7.5A (8~42v) HV UBEC for Lipoly.



The ESC I want to use was out of stock, so I did not order. More on that later.

Not sure about the ESC to use yet.
It definitely has to be one that can be programmed with a card. I just hate ESC-programming via Tx

The choice is between:
The 60A rated TURNIGY Plush 60amp Speed Controller, with burst current up to 80A.
And the 80A rated TURNIGY Plush 80A w/ UBEC Speed Controller, with burst current up to 90A.

The 60A ESC should be fine for the motor I chose. Maximum power draw of this motor is 55A. But on the other hand, what if I would like to upgrade the motor to a more powerfull one in the future?
Then again, HK has plenty of stock on the 60A ESC, where as the 80A ESC is out of stock most of the time...
I think I will sleep this one over ones more.

The gyro will be the DETRUM Head Locked Gyro GY48V. I bought this from Ebay,just to give it a go and it was cheap.

I first tried it on my HK-450 and with a digital servo the tail was rock solid. It was only after I switched the gyro on the HK-450 with a Telebee. That I noticed how nice the GY48V actually is. In the air both gyro’s are as nice. But the GY48V practically holds the tail also during take off! With the Telebee the tail has a much greater tendency to turn to the right.

So my new bird will get the GY48V.

I just love build threads.

Donnie D

The bird will be powered with a Mystery 6S 2800mAh 25S continues (30S burst) lipo, just ordered one (more to come in the future ). Also this one I got from Ebay, cheaper than HK (including shipping).



I also have two 3S 2450mAh 25S continues (30S burst) lipo's from my HK-450. These put in series should also be enough to power this heli.

Since HK in no longer carrying the Deans T-connectors due to legal issues, I ordered some of these XT60 Connectors Male/Female (5 pairs). I will use these in the HKH-500. Let's see how good they are.

Thanks Donny D!

Me too, so I figured I should do one myself

For the tail I am thinking of using this Blue Bird BMS-661DMG+HS Super Fast Digital Servo (MG) 6.4kg / .08sec / 46.5g.

Can't seem to find much reviews on the web though on this servo. Judging from the specs is should be okay. But is it suited to control a heli tail?

Hey guys,

I think I found my tail servo, a Hyperion Atlas DS20-GMD.

This standard sized digital servo also runs on 6.0V with the following specs:
speed = 0.05 sec/60 degr; dynamic torque = 2.0 kg/cm; holding torque = 4.0 kg/cm

I just love the metal gears.




Finless Bob used this servo in one of his builds, I can't find the video where he actually flies the heli, only the tail servo mounting video. In this video he mentiones that the gears are nice and tight, so not much slop!

I found this mod, to prevent static charge from building up in the tail. A static discharge could cause the Rx to malfunction.
This is only a problem with heli's using a belt to drive the tail. Torque tubes do not build up static charge. And mainly it concerns the bigger models, there are some reports over at the HeliFreak-forum on static (dis)charge problems with the T-rex 500.

To prevent static build up you have to (electrically) connect the two belt-pulleys.
Since I am gonna use a full metal tail box, I only need to connect the bearing of the tail drive pulley to the metal tail boom, using a small piece of cupper wire.
Better to be safe than sorry, I will implement this mod in my build.

Like shown on the left, in the picture below. Photo was taken by Gabor of the HeliFreak-forum, credits for this mod go to him.

Okay, so I thought it over and decided to go with the TURNIGY Plush 80A w/ UBEC Speed Controller.

It's in backorder at Hobbyking, so I'll just need to wait...
Ordered some bits and pieces at the same time. Silicone Wire 12AWG to make a serial cable for two 3S Lipo's, and spare parts for the bird itself. What goes up must come down

So this ESC it is:


Funny thing, this picture at HK is called hw_p80a.jpg. Does this translate to HobbyWing Pentium 80A. I would say the specs, shape and compatiblity with the programming card strongly suggest this.

another option for some will be this 80A Hobbywing ESC, it doesn't include a built in BEC but you don't want it to anyways, but its only $53. I use them on both of my ES600's and Blazemob also uses them on his HDX 500 and also his ES600. Soft start isn't the best but the ESC's really are great, my one is a year and a half old and still works great, Hobbywing's rule. I also use the Turnigy's but the Hobbywings are usually almost the same price and just a little better in my mind

$53 - http://www.hobbypartz.com/ho80abrescwb.html

Hey,
I bought that blue bird servo for my e-smart tail. But I didn't try it yet

Hey P3tras,

I saw a message at HK that wondered whether it was really a digital servo. I checked the Blue Bird website, here the servo is mentioned as standard servo and not as a digital servo. (anything in the your servo manual that would suggest otherwise?)
Anyway, that is when I decided to play it safe and go for the Hyperion servo.
It will arrive in today
But still have to wait for the T-rex 600 rudder servo mount....

Just received the Hyperion Atlas DS20-GMD servo in the mail

That is one nice and sturdy looking tail servo! Very quiet (not even the buzzing sound that the Hitec digital tail servo on my HK-450 makes) and fast servo. I am happy

Can't wait to see how it holds the tail!

Okay, I have started building

First the conversion of the plastic to the metal rotot head.



I immediately ran into two problems
1) The metal head came without the plastic radius arm on the wash out arms. So I need to use those from the plastic rotor head. These are fixed to the plastic wash out arms with two screws that go into a metal cylinder. Unfortunately this cylinder rotates within the plastic washout arm. So I can only remove one of the screws, without having to destroy the plastic washout arm in the process.
2) Movement of the swashplate around the central ball is NOT smooth (see picture below).
I contacted the seller on Ebay. I hope he is willing to replace the swashplate.

Hey Mozzy, Do you think you got a "returned" rotor head by mistake?

Hey Chief,

Don't know whether it was a "returned" rotor head. It looked new, no scratches.
The seller agreed to send me new swashplate. From what I understood from his/her Chinglisch it is send directly from the manufacturer.
Did not receive it yet.

The fat Mystery 6S Lipo does not fit underneath the canopy without some mods.
For starters I lowered the battery tray.

Replaced the plastic main shaft holders with metal main shaft holders (spare part for HK-500GT).

The width of the cyclic servo's fits the HKH-500 frame perfectly. But it lacks length, that's where the adapters that come with the fit come in handy.



I needed one adapter per servo to get a good fit. For the aileron and pitch servo the adapter needs to be put at the lowest part of the hole.
Two holes were drilled in plastic adapters to mount the servo's to.

In the picture below the bottom adapters are not modified.