Build Thread - HelixHeli G700 Conversion

[LoveToFly1]

i have never owned a gasser that weighed less than 12.5lbs ready to fly. i have seen some pretty interesting claims over the last few years on total weight of gassers. but in reality, they usually all end up around 12.5-13.5lbs (with an RC motor).

[jharkin]

My Helix is coming in around 12lb 10oz with the very light century muffler, no pull start, 2300 battery and generator system.

WIth no generator you might get it down to 12.5lb... maybe. Getting below that will be tough I believe.

[joecass2]

I think you can get it down to 12 by running the trex 600 fuel tank and using the HWC electronic igntion. This is one of the reason why I want to build this convertion.

[LoveToFly1]

The flywheel's centrifugal weight adds to the vibration dampening. I wouldn't be too anxious to pull it off and use a lighter flywheel. That's just me though.....then you have to add either an additional flight pack, or a larger one to keep the same flight times. Also more points of failure....maybe it has some pluses, but I don't see myself trying one.

[joecass2]

what servo arms are you guys using?

[joecass2]

Originally Posted by LoveToFly1

The flywheel's centrifugal weight adds to the vibration dampening. I wouldn't be too anxious to pull it off and use a lighter flywheel. That's just me though.....then you have to add either an additional flight pack, or a larger one to keep the same flight times. Also more points of failure....maybe it has some pluses, but I don't see myself trying one.

I'm still using the same flight pack 2100 ma getting 3 flights out of it probably can push out 4 but it would be close. I didn't notice any additional vibration in vbar log or in the Heli.

This is on the goblin I'm just starting to put together the helix conversion

[jharkin]

Originally Posted by joecass2

what servo arms are you guys using?

I tried the Futaba T-arms that come with the BLS451s. the outer hole at 19mm is not long enough for the large ball spacing of the align swash... In order to get the 9-10deg cyclic that Bavarian Demon setup wants along wit h12 degree collective I was binding the arms on the servo cases.

Going by Tins build videos I ordered a set of Align D6EF blue metal arms. I dont particularly like the idea of metal arms on a heli, but the length is perfect (22mm on center hole) and i dont crash much...

If you can find a plastic arm with 22mm spacing that will do.

Originally Posted by joecass2

I'm still using the same flight pack 2100 ma getting 3 flights out of it probably can push out 4 but it would be close. I didn't notice any additional vibration in vbar log or in the Heli.

This is on the goblin I'm just starting to put together the helix conversion

Thats impressive you would get that kind of flight times. On my setups I tend to burn 500mA per flight just driving the servos. On my 50cc airplane, the electronic ignition runs a seperate pack and that runs down faster than the flight pack. Call me old fashioned I still dont like putting the electronics on the same power bus as the ignition and I doubt I could pull off more than 2 flights on a setup like that (I must run longer flights).

In any case, I dont have any burning desire to try it because honestly at my level I'm not even using 100%, heck not even 80%, the capability of the 270 powered 13lb Whiplash. 300 power on a 12.5lb setup is already going to feel like a rocket to me.

The other thing that occurs to me... I love EI on my planks because it makes starting easier, helps run more reliable low idle, and gives better power through the midrange. In a heli where you are generally running in a narrow RPM range most of the flight the variable advance of the EI is kind of a wasted benefit I think.

Like LtF and Raja I'm going to stick with tried and true magneto.

[joecass2]

Ok thanks I'm running low voltage servos this is probably why I can run the 2100 pack. I have not seen any ill effects running the EI.

In the video looks like he is using the align arms but on the middle hole that's 19mm? Maybe I just need to watch the video again.

[rbort]

Just turns and turns and makes power for thousands of hours. I tried the electronic ignition in a G20 engine in the Radikal heli and while it worked it became problematic, gave me issues I didn't figure out right away. Eventually I had to replace it. Didn't leave a good taste in my mouth. Its more things that can go wrong in my opinion especially 1/2 the problems are like hard starting/quitting that seem to go away after the engine warms up slightly, thus keeping you guessing. I got videos of that stuff if you guys want to see what I mean.

-=>Raja.

[richmurphy83]

Double post

[richmurphy83]

I just bought a crashed 700 with busted frames for cheap money ($100) I am going to use for my donor. I was going to buy all the pieces separately to do the conversion but for thw price of the one way bearing I got the whole heli. I ordered up a 290rc motor with clutch from ebay for $210 shipped. I am waiting to order the conversion kit till I can decide if I want to run a generator or not, don't know if pieces are availiable separately after the fact.

I saw something a couple pages back about a different design that allows a gear ratio change?????? Can anybody confirm this rumor? If so I will wait to order the conversion.

[4 stroke flyer]

My understanding is that the new conversion uses the 700E heli parts or you can use the Hobby King version. I watched a guy a IRCHA fly one this year.

[LoveToFly1]

No adjustable gear ratio yet...only a new conversion with the 7.1:1 gear ratio. This is a great kit. My concern with your crashed Heli is that there is a chance nothing will be good on it.....but I do see what you mean by $100 being cheap

mother concern, a stock 290 is a vibration machine.....you may want to send it in to get it modified so it is more balanced.

[joecass2]

O no I just broght a used convertion kit with the old gear ratio. What is the benefit of the 7:1 gear ration more torque? I'm going to be using the TRM 300. Would the old gear ration be better because the 300 dose not rev as high as say the 275?

When will this new kit be available?

[richmurphy83]

Im hoping vibrations wont be too much of an issue. I don't plan on running a crazy head speed as I'm not a 3d flyer.

[LoveToFly1]

Originally Posted by joecass2

O no I just broght a used convertion kit with the old gear ratio. What is the benefit of the 7:1 gear ration more torque? I'm going to be using the TRM 300. Would the old gear ration be better because the 300 dose not rev as high as say the 275?

When will this new kit be available?

the higher gear ratio provides more "pop". The 300 will rev just like the 275 with the RJX muffler on it. the other mufflers are just too small. the older 290's didnt like to rev, but the 300 will rev just fine.

Originally Posted by richmurphy83

Im hoping vibrations wont be too much of an issue. I don't plan on running a crazy head speed as I'm not a 3d flyer.

you need to run at least 2000 with the older kit with the 6.76 gear ratio to keep the motor in the 13,500 range.

[richmurphy83]

So what is the new gear ratio? The website still lists a 115 main with a 17 pinion.

[rbort]

you need to run at least 2000 with the older kit with the 6.76 gear ratio to keep the motor in the 13,500 range.

You don't need to get to 13,500. You can run 1800 head speed at 12,200 and that would be no problem at all. I run my vintage 1005 gasser from 20 years ago designed with a 6.43 GR at 1800 to 1900 head speed and the 300 pulls out very well.

Richmurphy83, since you're only saying you're going to be flying crazy 3d try 1750 to 1900 head speed with the 6.76 anywhere in this range should be very reasonable.

However, listen to Mike and go get the motor balanced, the stock 29 would be a shaker. You can send it to Hanson if you like, he will balance used motors no problem. Probably cost you a couple hundred bucks but your heli will thank you for it.

Merry Christmas to All!

-=>Raja.

[joecass2]

Dose anyone know what would be needed to upgrade to the new gear ratio? Would I have to buy a hole new kit or just side frames and a pinon?

[richmurphy83]

I emailed hanson and they wanted more than I paid for the motr to balance it. Its a brand new motor and I got it for 210, he quoted me 260 to modify the motor. I was really hopi g to make this a budget build but if I have to send the motor out that throws the budget right out the window.