HK 500 GT Build

[Bodizapha01]

Originally Posted by Digger66

I am waiting on my HK500GT to arrive, and I guess a tail assembly replacement is in order. Is the Metal version from HobbyKing/ CopterX any better, or should I just get the Align one and be done with it?

Digger66,

From what I have read, even the metal tails from HobbyKing have their issues. On HobbyKing.com under reviews of the metal tail customers have stated that their grips have come flying off. Im assuming the hardware used in the plastic tail, and metal tail are the same. The screws seem soft and can't handle the load. If you do get a metal tail from HK I would replace all the screws with quality ones. As far as CopterX, I don't know. I haven't looked at them yet. I spent almost $80 replacing the entire tail (-boom) with the Align plastic stuff. I should have spent the extra $30 and just got the torque tube, but I was pinching pennys. I would recomend getting the torque tube which is around $100 out the door or the Align metal tail which I believe will run you around $70 out the door. One other thing have noticed too is my blade tracking always comes apart after adjustment. After doing some research I have found that the mixing arms need to be upgraded to metal, and some even recommend changing the ball links to Align as well. The stock mixing arms are a really soft plastic, and flex under load causing tracking problems. Those you can buy from HK if they are in stock. If not they are only $35 from Align. Anyways, looks like our cheap helis arn't so cheap after all. LOL.

[Digger66]

Thanks for the replies. Yea, the reason I went with the HK 500 was to save a few $$, but in the long run maybe I should have just went with the trex. I guess I will just go for the align tail assembly. I have the CX 450, and no issues with it yet. Even got the alum. V2 head and tail, and have not needed to install yet. I thought I was doing my credit a favour going with the HK500. I`m sure once I`m done with the build, she will be a fine bird.

[Bullitt5094]

Not sure why you would jump to going to Align. I got the CX 500 for 124.00 from Ehirobo. Then ordered digial cyclic servos, digital tail servo, 85amp ESC with programmer and 1600KV motor from Hobby King for $150. So you have a complete all-CNC, CF frame and CF Blade 500 that works for $275. The just add a gyro and receiver. Heck, build two for the cost of an Align kit. It's great when your spare parts is a RTF heli just waiting for you to install a gyro and receiver from the broken bird.

[redgiki]

Originally Posted by shizack

Most of the ones I've heard about flying off were due to the bolt that holds the grip to the hub snapping. Some blades have broken at the root, but that was a while back and rare even then. Usually with gung-hos trying to get away with 3300+ rpm head speed which isn't wise anyhow.

Quoted For Truth (+1, QFT, whatever). The stock HK500GT power system is usually the Turnigy Typhoon 1800Kv, and they ship a 13-tooth pinion with the kit. Using those two together leads to head speeds well in excess of 3,000 RPM.

Drop to an 11 or 12-tooth pinion on 6S LiPo, and you'll be fine. The tail will be solid, you'll be somewhere around 2400-2800 RPM, and I've heard NO reports of an un-damaged HK500GT tail exploding in flight below 3K RPM. I've heard of tails that have chewed into pavement explode at low RPM though...

[Digger66]

That`s the reason I went with the Copterx 450. The heli is good after setup. I was impressed with what I got for the price. I was hoping the 500 would be the same result. I would just hate to have to replace alot of parts to make the heli safe and flyable, that is my only concern. I am trying to keep costs to a minimum on this build, and yet have a decent bird.The servos, motor ,ubec, etc.. will be Turnigy products, less the gyro (gp750) and tail servo (ds520).

[redgiki]

Originally Posted by Bodizapha01

...one of the blade grip bolts snapped, and caused distruction of the entire tail case.

Quick question:

1. What motor were you running?
2. What pinion were you running?
3. What was your head speed?

If I don't miss my guess, it was probably:
1. Turnigy Typhoon 500 1800Kv (some are wound to nearly 1900Kv!)
2. 13-tooth pinion
3. 3200RPM+

Just for reference, I've been flying my HK-500GT on the stock tail now for MONTHS without incident, turning a head speed of around 2800 on a full pack, 2600 on an empty pack. Watch your head speed with this bird, yet again...

[rotorfan]

I do have the turnigy typhoon and did put on a 12t instead of the 13t it came with. got my gy611, but still cant test it Im having a problem setting up mt dx6i this is my first build and my first computer radio.

[belcom]

CopterX 500SE seems like a good kit. I just built it and did a first test hover. There were a couple issues like tail drive gear bearings and tail drive shaft bearings plus the tail shaft needed replacement. Both tail grip and main grip bolts I replaced with stainless steel and all is good. Head has no slop. So far I enjoyed putting it together much more than EXI which was a nightmare.

Originally Posted by Bullitt5094

Not sure why you would jump to going to Align. I got the CX 500 for 124.00 from Ehirobo. Then ordered digial cyclic servos, digital tail servo, 85amp ESC with programmer and 1600KV motor from Hobby King for $150. So you have a complete all-CNC, CF frame and CF Blade 500 that works for $275. The just add a gyro and receiver. Heck, build two for the cost of an Align kit. It's great when your spare parts is a RTF heli just waiting for you to install a gyro and receiver from the broken bird.

[Digger66]

The motor I am looking at is the Tunigy 500 @1300kv. I looked at the typhoon, but I don't think I need that amount of headspeed and power. Any thoughts on the tooth count on the pinion gear for some basic flying? I actually would like to get into some AP/AV with the 500.

[rotorfan]

I get about 2800 with a 12t on the typhoon.

[Bodizapha01]

Originally Posted by redgiki

Quick question:

1. What motor were you running?
2. What pinion were you running?
3. What was your head speed?

If I don't miss my guess, it was probably:
1. Turnigy Typhoon 500 1800Kv (some are wound to nearly 1900Kv!)
2. 13-tooth pinion
3. 3200RPM+

Just for reference, I've been flying my HK-500GT on the stock tail now for MONTHS without incident, turning a head speed of around 2800 on a full pack, 2600 on an empty pack. Watch your head speed with this bird, yet again...

All my electronics are Align. DS510'S on the cyclic and DS520 on the tail. The motor is the stock align (1600kv) with a 13t pinion and stock 60 amp esc on 6s. Not sure what the head speed actually was. I purposely went with the 1600kv because of post about the problems with the HK500GT tail system. I was very thurough with my build and never once nicked a blade or even touched a blade of grass with my tail. The bolt snapped with the helicopter still on the ground. I was able to put about 4 packs through it mainly hovering and some forward flights. I didnt want to do to much because I was afraid of a tail failure. In all honesty I was surprised after four packs that it did fail. I was starting to have confidence in it. This is a well documented problem with this helicopter but I am glad to see some are working out. Just wish it was mine.

[Bodizapha01]

Here are some pics of the tail. These were taken right after it happened. The pic with the tail on the ground was exactly where it landed. The heli spun 180 degrees and that's how it ended up.

[redgiki]

Wow, the head of the bolt sheared right off.

Nice photo documentation. EXCELLENT to see some proof of what's failing in these situations: the bolt's too soft. I always thought the failure mode was the whole bolt pulling out of the tail shaft (stripping threads) from overtightening of the tail combined with excessive head speed.

I'm going to go swap out my bolts with Align bolts from my spare tail tonight. Holy cow! Good work! Cheap fix for a little insurance.

[OB1 Kenobi]

While waiting for my ESC (Turnigy Tz85A) I ordered the metal tail set because I was afraid this (tail explosion) would happen to me.

I am no crash investigator but it would seem the retaining screw snapped off the tail rotor hub. So I think good HUB and good set SCREWS are a must. The weakest link appears to be substandard screws.

The screws that come with this kit are really BAD. One will notice this immediately as the socket heads round off easily even with a decent hex driver. REPLACE as many screws as you can with stainless or similar quality and throw away the stock ones. Don't forget to throw away the stock grub screws too. They can prove to be a pain. I know.

I still think with good tail setup (ie. Spartan DS760, BLS980 cheap prices from HK), metal mixing arms (Tarot part from Ac-Rc) and good screws, my first 500 will be best value for money. A few dollars more and the law of diminishing returns comes in. It just sits there right between crappy cheap on one hand and unnecessarily expensive on the other. Just right, dialed-in cost wise.

[Bodizapha01]

Glad I could help! I was very surprised how very similar the Align and HK plastic tail grips, blades, and case looked. Almost identical but I do also believe the plastic in the HK is softer as well. I would bet the HK metal tail assembly with good screws and the Align hub (for added assurance) would be a great solution.

[Bodizapha01]

Redgiki,
Are you still using the stock plastic mixing arms and/or the stock blades? My blades won't stay tracked. The heli is butter smooth with a soft lift off but once I give it a little throttle they come apart. Forget about idle up. Were talking Edward scissors hands when that switch is flipped. I can land, let it settle, spool up and lift off and they retrack but as soon as it gets some head speed it off.

[joeyhatch11]

You guys ever think of using Tarot replacement parts? There half the cost as Align and just as tough. I buy all mine from AC-RC.com. Although coming from HK there here within a week and that's normal shipping too, only $10. EMS is a bit more but you'll have your goodies in 3 days. I bought a 500 clone from Valuehobby.com for $75, replaced the tail assembly, rotor head and main blade grips with Tarot parts and it's been rock solid. I love my clone. From lack of waiting I bought some Align tail booms, main shafts and feather shafts but once I received my Tarot replacements, I see and feel no difference between them. Here are some pics of the clone.

[DerClown]

Guys, tell me, where to get that Align hardware pack for tail ? I'm also about to buy HK 500CMT kit
So I'm afraid of the tail explosion and etc.

[mark.w]

hi
joeyhatch11

if you dont mind me asking the tail you brought i also recently purchased an identical head and tail in black and silver of ebay, all has been well untill recently i smashed my helli up. rechecking thing the last few evening i decided to check the head and tail.

To my horror i found that the thrust bearings on tail were nearly all missing par a few like 4. did check my head and also found bent thrust bearing rac with bearing missing and washers that are realy poor in quality and outer bearing race channel were bearing run far to deeper grove were bearing sits and runs causeing the outer bearing race to wear on inner bearing assy. have replaced now with align parts.

Just wanted to mention this to incase you may have the same issue if the parts you have have come from the same manufacture.

Mark

[joeyhatch11]

Clown, check out AC-RC.com. You can buy Align parts or Tarot parts for the 500. The Tarot parts, as you'll see, look spot o to the Aligns and perform just as nice but at half the cost.

Mark, when I had to replace my tail assembly, all I ordered was the Tarot tail case. The tail blade grips I was able to reuse from the kit I bought at Valuehobby.com. I took a really nasty spill and bent the orginal aluminum frame all to hell. I've since replaced the frame with the Tarot silver graphite as you can see from the pics. All the thrust bearings, both head/tail, have been great and so has everything else. If anything replace the thrust bearings with the Align's rather than risking another problem by getting cheap replacements.

Here's the tail I bought. http://www.ac-rc.com/product_info.ph...6o99a4ivlrb660