General Project HK450GT

[Tony]

As some of you know, I purchased back my old HK450GT from Sam (Breez400) adn have been flying the crap out of it. Well, today I received my order from amainhobbies with a LOT of parts for it, and another 450 to be named later.

The parts for the HK450GT are as follows

Helical main gear
3.17 helical pinion 11T (low head speed, but the motor is underpowered so adds more torque to the head)
auto gear
tail drive gear
front tail boom mount (solid v3 mount, nto the block with seperate drive gear holder)
belt
tail boom
tail shaft

All of that stuff is Align. As I always say, if you have to replace anything, do it with Align if you are working on a clone. Adn that is what I'm doing. I decided to go with the helical gear mostly because I had 3 coming, and I was only going to use one. Plus, the pinions are cheap. Speaking of the pinion, they are aluminum and VERY light compared to the brass that came with it.

The reason I'm doing this is 1. the drive gear that it came with was oblonged and not runnign true. But, I couldn't find the drive gear that I needed, so I converted this over to teh v3 drive system and block. Best of all, it's a direct swap.

I should have ordered the Align one way sleeve that goes in the one way and also in teh auto gear. When I go to replace this auto gear or whatever, burn up a one way, then I will order the sleeve. I had to take a hammer to this one just to get it to fit. not exactly ideal lol.

Another reason I'm doing this is I think I'm too used to TT heli's and the way they free spin. And I wanted to put a good belt on this thing to test it. After I put the align belt on it, it was TIGHTER lmao. Talk about a fail. But, the belt needs to break in and get rid of the bends that it had when packaged. We will see how it does.

My next step is to replace all fo the bearings. Now I know I said I was going ot keep this all clone, but I just couldn't do that. I have to have quality and that is what I'm doing, making this a quality bird. Just wait until you see the next one hehe. I think you guys will like it if you are still into building clones.

I will post pictures after I'm done with it adn show you all of the parts that I replaced, and yes, a flight video as well. For now, here is the before flight video. It's just a random video that I shot of the heli when flying it around.

Remember, this is the before video that I just picked at random.
Flying & Glasses Audio Test - YouTube

 

[Tony]

Video is uploading now.

I may be changing the one way bearing sooner than I thought. I just went to put the blades in the holder, and the one way was locked to the auto gear. I think that is why it stopped so quickly when I landed it for the last time. You will see in the video.

I'm liking what I'm feeling, but it still needs to be dialed in. I need more cyclic pitch, that's for sure. The tail is solid, and the only gear wine you hear is from the auto to tail drive gear. Teh main gear makes almost no noise, it's quite nice!

 

[Tony]

Alright guys, here is the video with the new parts. The only noise this thing makes now is the auto to tail drive gear as posted above. I'm loving the sound of it. Now, with the bigger teeth of the 121T main gear, it's ready for more power. I have a motor on the way that I'm going ot test (have not used one before, they are pretty new) and if they work good, this one is getting a new motor/esc as well. It needs a LOT more power.

Finally I was able to get my fingers to work to bust off 3 flips with this bird. Tail blew out a bit on the first one, but the second and third one was pretty good. Need some more collective management to keep it at a steady altitude.

Here is the video!

HK450GT After Rebuild First Flips - YouTube

 

[Tony]

Here are the parts that I replaced.

 

[Tony]

Just did some calculations on my gear ratio. I had a 13/150 on there before and that comes out to an 11.538 gear ratio. Now, I'm running an 11/121 with a ratio of exactly 11:1. I calculated head speed at 11.1 volts on a 3500kv motor, and the new gear "should" be spinning the blades at 3531rpm at 100%. I don't think it's spinning that fast lmao. But it should when I get my new motor. Wait, the new motor is only 3400kv. That would bring me down to 3430 rpm at 100%. I think that would work. Now, I just need some servos with enough grunt to do all fo the stupid things that I'm about to do haha.

 

[Tony]

Figured out why there was no change in head speed from normal to both idle up's. I Had my Tx set on a flat curve in normal mode. It was 0 40 75 75 75. Well, when I set the ESC up, it saw 75 as full throttle. And would not go any higher. Wow, I have been flying at 100% throttle this whole time. I have since lowered it down in normal to 0 50 50 50 50, IU1 is 70 70 70 70 70 and IU2 is 100 100 100 100 100. This should make a bit of a difference on teh next flight lol. Talk about a moment...

 

[Dirk]

That's looking good Tony. Is't it amazing what a difference the helical cut main gear and pinion makes to the noise factor? On my align you mostly hear the blades and the tail rotor.

What do you call your heli now? FrankenLign? LOL

 

[Tony]

The auto to tail drive gear is now the loudest part of the heli. And I think I'm calling it the RCH 450. This is the helicopter that you see in teh flight school after all lmao.

 

[Dirk]

RCH it will be christened then!

I wish Align would bring out helical gears for the 450 as they do on the 700. The bird will be super quiet. I do think the " noisy" tail drive is probably what saved me from a bloody mid-air with a flock of geese yesterday. They have no regard for the "right of way" rules!!!

 

[Tony]

They have helical gears for the 450, i put them on. Or are you talking about helical auto and tail drive gears?

 

[Dirk]

Yes, helical gears on the auto and tail drive gear. I have the helical gears on the main and motor pinion.

 

[Tony]

Talking about this and watching the HeliMasters live on the internet makes me want to do some flying lmao. Too bad it's pitch black out side lol.

 

[Tony]

Well I just found out wht my one way locked up... no flying for me for a while... suckage!

 

[Tony]

And here is the result of trying to remove it from the auto gear. A brand new align gear, trashed by a clone sleeve. I should have known better...

 

[Karubah]

Can you push the metal piece out and replace it with one from another old gear that you might have lying around? It looks like it must have bound up to do that sort of damage.

 

[Tony]

SUCCESS!!! Just needed a bigger hammer! Now to find the sleeve to replace this one...

 

[Derek]

ya gotta love bigger hammers! well done, Tony! It wasn't the most "technical" approach, but sometimes to get the "effective result" you just have take "technical" and toss it out the window, lol.

 

[Karubah]

I knew you could do it.!!

 

[Tony]

Can you push the metal piece out and replace it with one from another old gear that you might have lying around? It looks like it must have bound up to do that sort of damage.

I wish it was that easy. The one way sleeve goes inside an aluminum sleeve that is on the inside fo the plastic gear. This is what makes Align gears better than the clones. The clones skip the aluminum and just go to the sleeve. This causes warping that can and will warp your gears and cause binding. However, with teh right size piece to fit on teh inside and a larger hammer, I was able to beat the piece out and save the gear, I think. I won't know until I get my Align one way, if I get one. I might just stick to my plan and keep this one all clone. Even though I want to put everything Align on it.

ya gotta love bigger hammers! well done, Tony! It wasn't the most "technical" approach, but sometimes to get the "effective result" you just have take "technical" and toss it out the window, lol.

Yup, the saying goes, "There's no problem a bigger hammer can't solve" lol.

 

[Tony]

Here she is with her new shoes. Love the pro style skids. Its starting to get a lot of align parts in it lol. So much for keeping it all clone. I will be taking the align main gear and pinion off though.