The official 600 stretch mod thread

[Luvmyhelis]

Originally Posted by oilfieldtrash21

As far as the main gear goes, is the KDE Mod 1 700 heavy duty 115T with the main gear case adaptor for the 600 the way to go?

Yes, I can't seem to kill mine. But blew through stock gears.

[oilfieldtrash21]

Sweet! That was the answer I was looking for. That pretty much covers the last few things I was questionable on ordering the right parts. This should make my project bulletproof, mechanically anyway. Thanks for all the help guys! Pics to come soon.

[Luvmyhelis]

Originally Posted by oilfieldtrash21

Sweet! That was the answer I was looking for. That pretty much covers the last few things I was questionable on ordering the right parts. This should make my project bulletproof, mechanically anyway. Thanks for all the help guys! Pics to come soon.

Just make sure you install the 3rd lower bearing main shaft mod if you plan on doing anything beyond mild sport? It is a fairly easy mod to do. Or the main shaft will twizzle around in the stock two bearing mains and you can still strip even the Kde gear.

What happens is the pinion mesh changes from tight to loose due to main shaft wag. The stock location of the two main bearing supports allows the gear to move around, especially with stock bearings. And it doesn't take much at the right moment for a pitch related move to coincide for the main shaft to lean over far enough for a large gap gear interface.

You really do need a lower bearing support UNDER the main gear to stabilize the gear set, or even the pinion pressure itself will try and push the gear away from the pinion interface. On a 600 some guys get away with leaving this area stock, but the moment you stretch it. It adds more stress specifically in this area. As the added torque applied magnifies the effect.

Once you do this the entire drive train settles down. I also use high end abec 5 to 7 bearings in my setups. 0 slop. Quiet!
Bob's RcTek three main shaft supports with angular bearings also works unbelievably well here.
No more Align cacophony chatter gear noise anymore. You will be quite surprised at how quiet your heli gets after doing this and using the Kde gear.

[oilfieldtrash21]

Originally Posted by Luvmyhelis

Just make sure you install the 3rd lower bearing main shaft mod if you plan on doing anything beyond mild sport? It is a fairly easy mod to do. Or the main shaft will twizzle around in the stock two bearing mains and you can still strip even the Kde gear.

What happens is the pinion mesh changes from tight to loose due to main shaft wag. The stock location of the two main bearing supports allows the gear to move around, especially with stock bearings. And it doesn't take much at the right moment for a pitch related move to coincide for the main shaft to lean over far enough for a large gap gear interface.

You really do need a lower bearing support UNDER the main gear to stabilize the gear set, or even the pinion pressure itself will try and push the gear away from the pinion interface. On a 600 some guys get away with leaving this area stock, but the moment you stretch it. It adds more stress specifically in this area. As the added torque applied magnifies the effect.

Once you do this the entire drive train settles down. I also use high end abec 5 to 7 bearings in my setups. 0 slop. Quiet!
Bob's RcTek three main shaft supports with angular bearings also works unbelievably well here.
No more Align cacophony chatter gear noise anymore. You will be quite surprised at how quiet your heli gets after doing this and using the Kde gear.

The kit I have, and I know how many feel about it, is the HK600. It already has the 3rd bearing. I got the kit for basically free so I couldnt pass it up. Ive replaced every moving part with align stuff. I ordered the upgraded 700 TT tail assembly and when I got it the bag said it was an 800 upgrade for the 700N, 700E, etc. It has 800 on the boom. Ive read that I would need to cut 40mm from the 700 boom to work with the 600. With this one it looks like I will have to cut 52mm to allow the TT gears to mesh. I was under the impression I was getting a 700 TT and boom when I ordered it, I guess I didnt read the fine print. I started assembling parts and realized I dont have the front TT bearing support so now thats on order. I'll look into the RcTek parts, I've read nothing but good things regarding quality and fitment. Are you getting those bearings from boca? Ive always gotten my bearings from avid when i was still racing but they were mainly rc car & truck bearings.

[Luvmyhelis]

I had to cut that boom down also when I did my stretch. But it worked fine. The material they use in the boom is rather soft and it is prone to flex badly when in use. Make sure you don't land hard either! I doubled up my boom support rods and it controlled it much better. I source bearings wherever the deals are to be honest. I have had pretty good luck with just about all the suppliers.

I have done a few builds using the older KDS framed heli which also has the lower bearing. And the quality of parts was right off the HK shelf. The swash was total garbage, and I had to replace most the bearings right off the bat plus the gears, TT boom junction support, and tail assy. Still, it worked. And flew well.

Plus I found something out. The main area where align has really improved their quality is in their new tail with the dual slider. I was pleasantly surprised.

[runesb]

Basickly whats realy crap in Aligns kits. MAIN GEARS.
Just build a 450 dominator, overall its a wery good quality, exept the main and auto gear and swash. only had issues with theyr 450 swashes..

What Align writes v2 on is quite good stuff. Especialy theyr Newly designed tail assy`s its a superb produdct.

[Luvmyhelis]

Originally Posted by runesb

Basickly whats realy crap in Aligns kits. MAIN GEARS.
Just build a 450 dominator, overall its a wery good quality, exept the main and auto gear and swash. only had issues with theyr 450 swashes..

What Align writes v2 on is quite good stuff. Especialy theyr Newly designed tail assy`s its a superb produdct.

Bro, throw a Microheli cnc milled delrin main on that little beast. I ran those on all my 450s earlier. And it really cleaned up the mess.

[utrinque]

Originally Posted by utrinque

10mm main shaft is ok for 700. Compass 7HV has 10mm.

12mm is ok for 800. Align offers stretch kit for T-Rex 700.

I am going to stretch Assault 700 DFC to 800mm. Align drive train fits.

https://www.helifreak.com/showthread.php?t=584038

[oilfieldtrash21]

Ok, I got a lot of my parts in and trying to assemble the main shaft and gears. I ordered the rc-tek hub that uses the 700 main gear, KDE 115T MOD 1.0 main gear, Align 131T M 0.8 tail gear and OWB shaft part# H60139A. When installed as intended, the main and tail gear touch before the holes ever line up between the main shaft and OWB shaft. I've tried every possible combination and nothing works. My original intentions were to order the KDE hub. The page for that part on helidirect had a list of parts that would work. I ordered what was suggested by KDE except I went with the RC-Tek hub instead. Surely the KDE and Rc-tek hubs are machined pretty close to be interchangable or I might be totally wrong in assuming that. Any ideas?

[Luvmyhelis]

Originally Posted by oilfieldtrash21

Ok, I got a lot of my parts in and trying to assemble the main shaft and gears. I ordered the rc-tek hub that uses the 700 main gear, KDE 115T MOD 1.0 main gear, Align 131T M 0.8 tail gear and OWB shaft part# H60139A. When installed as intended, the main and tail gear touch before the holes ever line up between the main shaft and OWB shaft. I've tried every possible combination and nothing works. My original intentions were to order the KDE hub. The page for that part on helidirect had a list of parts that would work. I ordered what was suggested by KDE except I went with the RC-Tek hub instead. Surely the KDE and Rc-tek hubs are machined pretty close to be interchangable or I might be totally wrong in assuming that. Any ideas?

The KDE gear needs to be spaced so that it sets between the tail drive gear set upper gear and lower gear set. The space is pretty small. It all depends on where your middle main shaft bearing support is seated. I have had a couple helis I had to move that upward with. And my recent one where I had to add two small 10mm x .020 spacers above the gear to make it fit right. Also I have relocated the tail boom support that holds the tail drive gear set around to help fit these. You have lots of options to make this work.

[338federal]

Hi stretch dudes. I have 600E pro with stretchkit. I have tested to fly with 690mm blades and it is awesome and very stable. Sometimes the skids shakes a little. With 625mm no shake. I am gone test with the same rpm like i tested with 690.
Some dudes are writing about 700 head and the hole package. Maingear, shafts and so on. What parts do i need. Specified, i am dumb Swedish old grumpy man almost 40.

[oilfieldtrash21]

Hey guys! Been a while since I posted on my build. I got most everything installed and the gear issue worked out. I ended up going with the Robird G31 for the gyro. I ordered a motor for the bird, http://hobbyking.com/hobbyking/store...ter_Motor.html

just because they had it for $76 vs the $250 for the scorpion 4035-530Kv. I just wanted to give it a shot. Well I get the motor in and the box it came in has a sticker on the bottom with with a part# and lists it as a scorpion 4035 530Kv. The specs are identicle to the scorpion. Is this a true scorpion motor only silver instead of gold? Havent installed it yet, still have to trim the frame for it to fit. I was just shocked to see "scorpion" on the box. Anybody have any thoughts on this?

[Luvmyhelis]

Originally Posted by 338federal

Hi stretch dudes. I have 600E pro with stretchkit. I have tested to fly with 690mm blades and it is awesome and very stable. Sometimes the skids shakes a little. With 625mm no shake. I am gone test with the same rpm like i tested with 690.
Some dudes are writing about 700 head and the hole package. Maingear, shafts and so on. What parts do i need. Specified, i am dumb Swedish old grumpy man almost 40.

Man, so sorry. I just now saw this post. My apology for no one answering. Naw, the 600 head is more than enough. I have run half a dozen different styles. Just run a non dfc head for the stretch. The main gear will def need to be beefed up or you will most likely strip it on easy pitch related moves. Align does not build great gears. Kde mod 1 15T gear and their hub. Rc Tek also makes a fantastic hub for this. I run the longer nitro shafts or the HK version. I prefer CF booms so run the 700 version. It is easy to run the 700 TT systems. And as seen def run the lower third bearing support. That is just about it.

Originally Posted by oilfieldtrash21

Hey guys! Been a while since I posted on my build. I got most everything installed and the gear issue worked out. I ended up going with the Robird G31 for the gyro. I ordered a motor for the bird, http://hobbyking.com/hobbyking/store...ter_Motor.html

just because they had it for $76 vs the $250 for the scorpion 4035-530Kv. I just wanted to give it a shot. Well I get the motor in and the box it came in has a sticker on the bottom with with a part# and lists it as a scorpion 4035 530Kv. The specs are identicle to the scorpion. Is this a true scorpion motor only silver instead of gold? Havent installed it yet, still have to trim the frame for it to fit. I was just shocked to see "scorpion" on the box. Anybody have any thoughts on this?

They do still carry old Scorp stock there! And they may be selling HK mass produced versions but not allowing their name to be used. Also hover and they will offer it at $76.35. Nice deal. So I wouldn't doubt you may have gotten one. Congrats if you did.

[Atomic Skull]

Originally Posted by SidewaysLS4

Any good source of 1/4" wide XL pulleys that will adapt to the Align drive gear/shaft, and a 1/4" wide 5mm ID pulley for the tail shaft (using custom length 5mm rod stock for my T600 belt tail housing)

9T 1/4 XL pulley for 5mm shaft.

http://www.hobbyking.com/hobbyking/s...ly_Metal_.html

9T 1/4 XL pulley for 6mm shaft (should fit 6mm TT tail rotor shaft).

http://www.hobbyking.com/hobbyking/s...ulley_Set.html


Note that the new "DFC" belt unit uses a TT mounting sleeve with the bearings removed so there is enough room for a belt with a 9T pulley despite the narrower opening.

Also the DFC belt unit has slider geometry issues so converting the TT unit to belt driven is probably a better option if you want the 2 sided slider. See this thread for details on the problem with the new belt unit:

https://www.helifreak.com/showthread.php?t=612542

[oilfieldtrash21]

Had my first test flight with the stretch, had a couple issues. First, no matter what I tried I could not get the 780mm blades to track true. After several attempts, it seems that the vibration was too much for the gears in the Hyperion DH20x's and cracked the output gear on 2 of the servos. Not sure if the tracking issues was from the blades being "cheap" but I went ahead and ordered a set of 810mm Align blades. The 780's balanced out perfect but wouldnt track, not sure if the blades were the culprit or the align rotor head being used with rjx grips. There was some play between the align head and rjx parts which I shimmed up to get as close a possible but still had problems or it could have been some what due to the servos or a combination of all 3. Not really sure but to eliminate any future problems I ordered the rjx rotor head and metal gear trains for the hyperions. As far as the HK "scorpion" motor, runs very smooth and seems to have enough power to swing the 780's goverened at 1800, 1900 and 2000 rpm. I tried to set the rpm to 1600 in the castle software but it was too low to be governed and it was noticeable when the esc was constantly hunting for rpm. Not to mention the esc was getting too hot for my comfort at that rpm. I was running a 15t pinion but I put in an order for 12-14t pinions. Overall I was impressed and excited/scared on the first spool-up, this is my first "large" bird and im hooked!! The rotor wash from just a hover was mindblowing, considering my main bird is a t500 with 470mm blades on 6S. I can see this addiction is going to only get worse. Parts should be delivered today, so I will be getting pics up that I've been promising. Between 2 weeks offshore, having to go out of town for training when I'm onshore and normal husband/daddy duties only leaves me time to work late a night. Thanks guys for all yall's input on helping get this baby airbourne for the first time. Couldnt have done it without the wealth of information on these forums.

[Luvmyhelis]

Yep, sounds like it might be both in the head and also maybe more the blade profiles themselves. I find with cheapo blades that the pairs rarely match in actual profiles, so one produces more lift and the other more drag. So they run out of track and also phase. My best results were using the Edge 813's.

Also you will need to run harder damps to control the blade mass if possible? I ran the Rjx 600 head and 700 grips to allow the grip spacing to be wider for these fat grip blades. These fly ok but vibe spike viciously when doing any hard moves. As all they are damped with are rubber O rings. I also successfully ran the Compass 6HV head and it performed flawlessly. Both had to be modded though to work properly.

[runesb]

Y can run flat th curve. Cc can handle quite low th%... as long y dont stick bang. 1900/2000hs is quite high if y fly general / sport style.

[oilfieldtrash21]

I'll have to try the compass head. I got the rjx one in and it wont work since I'm currently set up for dfc. Probably going to convert it back to non-dfc and go with your suggestion. I had it governed that high because at the time all I had was a 15t pinion. I installed the 12t last night and set the gov at 1600, 1700 & 1800. I guess I could run a flat curve, I've always ran a gov on my t480 & t500 and liked it. I'm by no means a hardcore 3d pilot, I enjoy the sport flying and my skills have progressed pretty well in the short time I've been flying. I have the really hard dampners in the 600 dfc head not sure of the durometer but if memory serves me correctly its 80 I believe. Still dont have 100% faith in these hyperions. I installed all metal gears and 2 of the 3 are "notchy" in their motion. The one that didnt strip out the plastic gears is the only one that moves smoothly with the new metal gears. I've rebuilt them several times to makes sure everything is correct and the notchy feeling is still there. I have a couple brand new dh20x's laying around, I may put the metal gears in those and give them a try. Too much invested at this point to take a chance on a servo failure.

[runesb]

Still y can go down on your pinion, dont need that much hs i sport flying either.

[oilfieldtrash21]

What hs do you suggest with 810mm blades? I have 115t main and 530kv motor.