GV-1 Can't get it to work properly.

[Curtis Burns]

I have just installed my GV-1 on my 50v2 / OS50 and when I turn the GV-1 on the heli's head speed will not go high enough to even lift off. As far as I know I set it up properly. I followed every step to the letter and thought it was easy to set up. When the engine isn't running the throttle follows the gimbal whether the GV-1 is on or not. With the engine running, the GV-1 keeps the head speed real low. I set the gear ratio to 8.5 and then just to see what happens I set the ratio to 4.25 and the heli would just barely lift.

gear ratio set to 8.5
both magnets installed the right way (97%)

normal mode GV-1 off
idle up 1 head speed set to 1800
idle up 2 head speed set to 1800

Then I set the speed switch to another 3 position switch to help me diagnose the problem. Didn't help.

The heli flies fine as long as the GV-1 is off.

I finally gave up and decided to try my first auto. It wasn't as hard as Real Flight. I spent the rest of the daylight doing 5 to 7 foot autos. I did about 20 of them and didn't break anything even though I seem to have a bad habit of hovering 1 or 2 inches until it won't hover anymore and then it just kind of "plops" down.

Curtis

[WillJames]

What radio are you using. Has the engine been broken in yet?

[Matthew]

Yea If your useing the 9c I know you need to go to the second Gov screen and switch it to act.

[Greg McFadden]

yep. you've got both magnets going the same direction, one should be flipped WRT to the other. on mine one says 97% and the other 1% basically what is happening is that it thinks that the engine is running twice as fast as it really is. if you have say a 9:1 ratio and wanted to correct for this using the gear ratio settings you would have to set the ratio to 18:1. I do not know if a GV1 can be set that high going down in gear ratio means that for a given headspeed the engine must run slower, as far as the math is concerned.

[Curtis Burns]

9CHP
one gal of fuel run thru so far
Gov is activated in the 9C
All switches are working properly in the direction I want.

OK, I tried setting the gear ratio to 17:1 but the GV-1 only goes to 15:1 so I turned one of the magnets over and set the ratio back to 8.50:1. I went back through setting my 9CHP and the GV-1 and didn't find anything wrong with the setup.

I went out side and tried it out and it seems to be way over speeding. Right as the head and blades started to do their "thing" I shut the engine off.

It's possible that I've just never seen my heli's head turning 1800 RPM and that my cheap woodies I bought to learn on won't handle 1800 RPM.

Unfortunately I don't have anyway of confirming head speed.

I found another thread about the same problem:

https://www.helifreak.com/viewtopic....&highlight=gv1

But that's not it either.

Curt


PS.

For those of you wanting to remove your magnets for whatever reason: The best way is to touch the magnet with a hot soldering iron. The magnet will just float up. Just don't leave it on more than needed or you will damage the plastic fly wheel (if you have a plastic fly wheel).

[Greg McFadden]

also keep in mind that touching the magnet with a soldering iron WILL heat the magnet beyond the point where it destroys some or all of the magnetic properties of the magnet (while you got the magnet off, you will probably need to buy a new one if you need it to be magnetic). 1800 does scream depending on your pipe. what was the max rpm shown on the GV1? (fly it a bit and then set her down, shut off the engine, and then click through the menu to find it). shoudl be right after or right before the "rpm" menu that it starts up. if that says zero your GV1 was not engaging. if it says 1850 or something like that, the GV1 thought your max rpm was 1850 and so forth.

[Curtis Burns]

OK, I just realized the plastic covering on my blades was very loose causing the "thing" they do at higher RPM's. So I re-shrunk the covering and fixed that problem.

I just lowered the RPM setting on the GV-1 to 1400 s1, 1500 s2, 1600 s3 and the GV-1 to see if I could tell a difference and I could so the GV-1 is working properly. @ s1 the heli just wobbles and @ s2 the heli lifts but is very sluggish and @ s3 the heli flies but barely.

In other words, it's me. Turning the magnet around fixed it.

Thanks for everyone's help on this.

Curt

[Dan Lewis]

When I test my gv1 this weekend, I plan the use a tach. If I didn't have one, I would ask around and borrow. I simply don't trust new electronics and I don't plan on trusting the gv1 initially, being this is my first experience with one. I was putting the magnets in mine a couple nights ago and called a few people to clarify this part of the instructions. It refers only to one magnet installation and is a little ambiguous about the other in a special note on the next page. The note only says to install the second magnet for balance. This is confusing because the instructions are a little on the terse side.

In regards to the 1800 headspeed with woodies, I never ran mine that high. I try to run carbons right at 2000 which puts my os .50 right at it's sweet spot (17,000). This is what I consider optimal and what I will expect the gv1 to maintain for me. Try setting your gv1 at 1650 w/woodies and increase it as you're comfortable. Maybe that will be better and let you ease into the new gv1 setup. If you have setup a switch that lets you turn off the governor and go back to your regular curve, then experiment by flipping it on and off in flight. ...just some thoughts. I'll know more after this weekend hopefully and plan to share whatever I learn.

[Dan Lewis]

glad you fixed it - I learned something too

[megarckid]

[Curtis Burns]

I learned a thing or two also...............governors are kewl and Futaba dropped the ball on their instruction.

The GV-1 has no problem holding whatever RPM I tell it to.

I'm hoping to use the GV-1 as a tool to learn how to set my throttle and pitch curves up by listening to the engine run with the GV-1 on then turning it off from the TX and noting engine RPM changes. I should be able to change the curves to match what the GV-1 is doing, right?

Curtis

[Greg McFadden]

you will be able to do that to a point, but where the gov. excells is compensating for cyclic inputs. all the pitch curve does is try to match your throttle to a given pitch of the blades, and the only way to take into account the cyclics is with mixes or a governor. what the governor will do is maintain headspeed when you heavily load the head with cyclics at little pitch (for example, one of many instances) with jsut straight curves no mixes you bog the engine in this instance because without mixes the throttle is still set at "putz" level which you probably set by just climbing out and seeing how she felt. now you can mix to achieve something like the governor, but you have to be VERY careful not to overdrive the throttle servo when doing these mixes (i.e. runs past the endpoints you set in the TX). As of right now I don't know how you can tell a 9C not to overdrive (know you can do it with a Z) and I am rather sure that JR does not overdrive the servo. (I suspect that the overdrive is a remnant from plankar code that hasn't been changed for some reason.....)

[Curtis Burns]

That's some good info Mr. McFadden.

Anyone have any clue what percentages to start with on the throttle / cyclic mixing?

Heres what I have:

50v2
9CHP
os 50 ring
woodies
30% cool power
idle up 1 throttle 100% 75% 50% 75% 100%
Pitch 0% 25% 50% 75% 100%
angle of attack -10° 0° +10°

Thanks

Curt.

[Dan Lewis]

I use 15-20%. I arrived at this after a few flights of testing continuous tumbles/rolls. Once the governor is running, I expect to get similar or better results.

[Greg McFadden]

be careful with your 9C. one of my flyin buds put in 30% mixin but his heli flew like crap afterwards... he was confused. the reason was that on his R30V2 the throttle servo was twisting the entire servo tray all over hell and back when at high collective and inputing any cyclic. so BE CAREFUL as I am not aware of a setting in the 9C that turns off this overdrive. test by setting to full collective and moving the cyclics. watch the throttle servo and servo tray

[Dan Lewis]

Yes, binding can be bad. Last month up at Chattanooga I switched radios to my new 9Z and forgot to check for binding of cyclic before flying. My left/right cyclic had reduced end points in my 9C model that I forgot to transfer into the new model on the 9Z. After doing a post event check back here in Tampa, I found my aileron servo gears stripped. My last flight up there could have ended ugly.

While I can't imagine a need to give full collective while giving full cyclic, if I did, it would bind my throttle servo slightly using my 9C. Any more than 20% isn't necessary on my setup, fortunately. The engine is pretty powerful.

Where do you set the overdrive safety feature in the 9Z? The Z is a lot harder to learn and I don't have a manual.

[Curtis Burns]

Greg:

The 9C WILL over drive any servo. According the 9C online manual the only way to over come this is to "buy their flagship radio the 9Z" which is a bunch of crap. For what my 9C costs, I don't think that feature is too much to ask of the software writers. According to http://www.raptortechnique.com/ you can run the sub-trim all the way over and stop or minimize this problem without side effects. Their theory is that the servo "bottoms out" before anything else and if I remember correctly they said that the radio will not try to send a servo past the "bottomed out" state. This is NOT the case with older Futaba systems and I haven't tried it with the 9C yet but I'll let you know what I find out.

Curt

[DavidH]

Originally Posted by Dan Lewis

Where do you set the overdrive safety feature in the 9Z? The Z is a lot harder to learn and I don't have a manual.

Dan,
There is program in the 9Z for cyclic to throttle mixing. It will not overdrive the servo no matter how much throttle is being added when the cyclic is moved.
This is a dedicated program for cyclic to throttle mixing. Go to the CND menu. Now in the lower left corner on the last line is the SWP menu. Now activate it in each flight condition that you want cyclic to throttle mixing.
Set the precentage to your liking. The default is 50%. No matter how high or low you set the precentage, it will not overdrive the throttle servo. This mix will work when the cyclic is moved in either direction. You do not have to tie up two P-mixes, this is a pre programmed cyclic mix for the throttle.

David

[Dan Lewis]

That's too easy Thanks David :mrgreen: