Synergy Tech Support

Synergy Electric Helicopters => Synergy 766 => Topic started by: Chris Olson on January 01, 2018, 01:05:44 PM

Title: 766 Gasser
Post by: Chris Olson on January 01, 2018, 01:05:44 PM
For Christmas this year Santa had a bit of a problem. Only halfway thru my list he was over maximum takeoff weight. So he had no choice but to dispatch The Brown Truck with my new 766 kit in it. But even The Brown Truck couldn't carry all of it. So the next part came from Carey Shurley at Gas Powered Helicopters in the good old USPS truck with my conversion kit and TRM Power Pipe.

I just got started on assembly of my 766. But I have an 806 gasser here with a Toxic VX300 in it that I'm putting a Pixhawk autopilot in with a downstream Futaba CGY750. The bench is kind of a mess right now, but I have the sub-assemblies from the donor kit built, and part of the gasser frame assembled for the 766. My 766 will have a Zenoah Toxic VX310, which is still a couple weeks out from being built at TRM Power. Carey will be sending that when it gets built.

I'll have some more photos of this build as I progress with it.

https://photos.app.goo.gl/yFi1FAimYohGPGAL2

https://photos.app.goo.gl/BOdyGqg1KTZTVRxt2

https://photos.app.goo.gl/b5paYQKtX8hw3UMf1

https://photos.app.goo.gl/44UOdwnuZ6f9QPHJ2
Title: Re: 766 Gasser
Post by: Chris Olson on January 01, 2018, 08:46:32 PM
There's too many small details to show everything on a build for one of these. The assembly manual for the gasser conversion is 60 pages.

Obviously the electric frame sides, battery tray, and a few other small parts like the motor mount and doublers are not used for the gasser conversion. Here is a couple shots of both sides of the frame with it married. And one of the primary drive and clutch bell. The belt primary is a .917 ratio, the pinion gear is 17t. So the final drive ratio is 7.5:1. 10,450 engine rpm is 1,400 rpm headspeed.
Title: Re: 766 Gasser
Post by: Chris Olson on January 02, 2018, 12:30:00 AM
Closeup photo of the primary belt drive and clutch, and top start shaft. The pinion shaft bearing blocks can be slid back and forth to adjust main drive gear backlash. The belt is adjusted with set screws in the holes in the clutch bearing blocks that push against the pinion shaft bearing blocks.
Title: Re: 766 Gasser
Post by: steffgiguere on January 02, 2018, 06:39:26 AM
A buddy of mine at our club did the same conversion, flies great, looks great.
Title: Re: 766 Gasser
Post by: Chris Olson on January 02, 2018, 11:48:19 AM
Yep, very impressed with the conversion kit. It is extremely well designed.
Title: Re: 766 Gasser
Post by: Cliff Chmiel on January 20, 2018, 08:09:33 AM
I have the 766, I was thinking the same, very expensive upgrade. what is the final weight? 
Title: Re: 766 Gasser
Post by: Chris Olson on January 20, 2018, 09:02:14 AM
Actually, if you start with a new build and compare the cost of a suitable motor, 160HV ESC, and four batteries the cost between a gas conversion and the electric is not all much different.

Takeoff weight is about 14lbs with the gas conversion, full of gas. The tank that comes with the kit holds 560cc and will fly it for 15 minutes at balls-out 3D power. 21 minutes for scale/sport at lower headspeed.
Title: Re: 766 Gasser
Post by: Cliff Chmiel on January 20, 2018, 01:17:30 PM
Nice
Title: Re: 766 Gasser
Post by: Chris Olson on February 04, 2018, 10:30:31 PM
Didn't have much of a chance to post any more build photos, but got about one hour of flight time on it now. Equipped with a Pixhawk 2.1 autopilot and extra-clearance landing gear with a belly rack to mount a 27oz DuBro belly fuel tank, and payload.
Title: Re: 766 Gasser
Post by: Cliff Chmiel on February 06, 2018, 08:27:20 AM
Looking good, can we get some video?
Title: Re: 766 Gasser
Post by: Chris Olson on February 06, 2018, 08:41:06 AM
Not right now. We had a couple nice days and now it's 15 below zero here again.
Title: Re: 766 Gasser
Post by: Cliff Chmiel on February 09, 2018, 12:45:57 PM
Bummer,
Title: Re: 766 Gasser
Post by: Chris Olson on June 10, 2018, 07:16:58 PM
Looking good, can we get some video?

Here's a video flying a crop insurance flight with the 766 Gas. In UAV configuration with 75 minutes fuel onboard it weighs 20.5 lbs. I'm using the helicopter for a different purpose than what most people buy them for.

https://youtu.be/pPoiQqg4d3A
Title: Re: 766 Gasser
Post by: Rodney Kirstine on June 11, 2018, 08:18:00 AM
That's really cool Chris.  What flight controller are you using?
Title: Re: 766 Gasser
Post by: Chris Olson on June 11, 2018, 08:41:48 AM
It is a Pixhawk 2.1 with ArduPilot in it.
Title: Re: 766 Gasser
Post by: Cliff Chmiel on June 13, 2018, 08:18:10 AM
Very cool, great job