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Old Sep 27, 2011, 08:27 AM
Team Wack-a-Mole
Melnic's Avatar
Maryland
Joined Oct 2008
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Dillzio,
I'm wondering if you had a servo lock up. One servo pulling up will make it kind of snap roll into the ground when you are low. We have a number of funjets at our field and we are often in a pissing contest to get the fastest speed low on the deck. Some people have gone too low.
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Old Sep 27, 2011, 08:41 AM
d_j
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Originally Posted by Melnic View Post
Try launching with less than full throttle. You don't need full throttle with the funjet to launch.

I'm trying to work on some instructions for an elevon mixing gyro system using a mixer and when not using a mixer.

Basic Gyro on a plane instructions (does anyone ever read post 1 of a thread?):
http://www.mycoolrc.com/gyro/indexnew.html
I tried the launch at 1/2 throttle and also at 1/3, i am not flying with a 3s setup but with a 6s setup, so the plane is kind of heavy.

When you have your instructions ready i am really interested to read it.

when possible i prefer to do not use an external mixer
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Old Sep 27, 2011, 08:56 AM
Team Wack-a-Mole
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Maryland
Joined Oct 2008
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This guy said I could re-distribute his image. (see below)
you test it just like a single gyro but if you may have to reverse only 1 gyro.
Get everything working w/o the gyro then install the gyro.
For a Label-Up gyro, you face the right gyro forward and right. Left gyro has label forward and left. (see 2nd video below at the end for my gyro installation)
I did this once and used about 60 degrees and a gain of about 30% using 2 GY48V gyros.
My plane (cough..cough) dog house was a horrible flyer and would yaw and roll really bad on me. Nearly impossible to land under control. We tried landing it and I could never get it slow enough to land without flipping over w/o the gyro. Then we added the gyro and every landing was nice so long as I did not turn after landing.

Video June 2010 with no Gyro
Snoopy vs. Red Baron Skit FSA 2010 (7 min 24 sec)


Video June 2011 WITH 2 gyros and no mixer
FlyingThingz Snoopy Doghouse with Gyro (1 min 59 sec)

Snoopy vs. Red Baron 2011 (5 min 40 sec)
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Old Sep 27, 2011, 08:54 PM
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Australia, SA, Parafield
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Originally Posted by d_j View Post
i want to read the all the pages, but it takes a long time to read all the pages. I understand what is happening when i install a gyro, but the problem is that i do not know how to install the gyro so that both ailerons are working correctly and that the gyro do not affect my elevator. I can install 2 gyro's on both channels but there should be a better solutions with only 1 gyro.
From what I've read, it is OK to hook the gyro up to just one aileron, if you want to mainly correct for torque roll to the left you should put it on the right aileron, because the aileron that goes up makes more of an effect than the aileron that goes down.

On the funjet ultra the ailerons also function as elevators, so technically they're not ailerons or elevators, they're elvons. For this reason the gyro is always going to have an effect on the 'elevator' as well as the 'ailerons', they're the same thing. The gyro will not correct attitude though (what the elevator normally controls) unless it's installed on that axis. A typical gyro installation will only correct for changes on the roll-axis.

How can you get it working both ailerons? The easiest way is to disable the delta mixing function on your radio, and use a V-tail mixer on the jet, that's what I've done. Then you can install the gyro on the aileron channel before the mixer, and then the mixer will filter the gyro's input to both elvons. Just make sure it's a good v-tail mixer, there's one made by GWS that's supposed to be really good, and it's quite cheap from hobbyking (thats the one I use). If you don't want to use a mixer, the other way is to use two gyros, one on each elvon.

A good place to find they gyros is ebay, you can get them for under $15 delivered. I like the look of the Titan 720 because it has all square sides (easier to mount on its side, as you need to do for controlling the roll axis), and it's fully functional (can be adjusted from a spare channel on your radio, has HH and rate modes).

DJ, rather than reading this whole thread, or asking someone else to figure it out for you, I would strongly recommend reading Melnic's link:
http://www.mycoolrc.com/gyro/indexnew.html
It is the best, and easiest to follow information source on fitting gyros to RC planes that you're ever likely to find.
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Old Sep 27, 2011, 08:59 PM
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Australia, SA, Parafield
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Quote:
Originally Posted by Melnic View Post
Dillzio,
I'm wondering if you had a servo lock up. One servo pulling up will make it kind of snap roll into the ground when you are low. We have a number of funjets at our field and we are often in a pissing contest to get the fastest speed low on the deck. Some people have gone too low.
Actually, one of the ailerons was ripped off, but I assumed it happend on the crash, not in flight.
I haven't actually tested the electronics/servos yet, seeing what my beautiful funjet has been reduced to is still too painful
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Old Sep 27, 2011, 09:17 PM
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brace's Avatar
Australia, NSW, Ashby
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Originally Posted by Dillzio View Post
Actually, one of the ailerons was ripped off, but I assumed it happend on the crash, not in flight.
I haven't actually tested the electronics/servos yet, seeing what my beautiful funjet has been reduced to is still too painful
Get the hot glue gun and CF rods out, you would be amazed how they come back together. Some hot water as well to bring back some shape helps as well. But yeah always tough when you see a model fitting into a very small box.
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Old Sep 27, 2011, 09:35 PM
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Get the hot glue gun and CF rods out, you would be amazed how they come back together. Some hot water as well to bring back some shape helps as well. But yeah always tough when you see a model fitting into a very small box.
Lol, have you seen the pictures?

That fuselage is pretty mangled! It reminds me of Sarah Jessica Parker's face with no make up on.
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Old Sep 27, 2011, 09:57 PM
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Quote:
Originally Posted by Dillzio View Post
How can you get it working both ailerons? The easiest way is to disable the delta mixing function on your radio, and use a V-tail mixer on the jet, that's what I've done. Then you can install the gyro on the aileron channel before the mixer, and then the mixer will filter the gyro's input to both elvons. Just make sure it's a good v-tail mixer, there's one made by GWS that's supposed to be really good, and it's quite cheap from hobbyking (thats the one I use). If you don't want to use a mixer, the other way is to use two gyros, one on each elvon.
Fantastic advice. I've been wondering how to do this with gyros too! However, there is a way to perhaps even solve this problem, or at least most of the problem, on a jet like the FunJet, with *no* gyros. I hope I'm not restating something someone has already said on this thread, so if I am, I appologize, but here is how:
use a computer radio to mix the throttle to the ailerons, so that as you apply full throttle, the mix automatically moves the ailerons to counter the torque roll of the prop. This may require 2 mixes, however: 1) throttle to right elevon, 2) throttle to left elevon. Play with the master-slave % adjustments until you get the proper mix for your setup and flying style, to fully counter the torque roll as you desire.

The only problem with this no-gyro option is that the roll effect of the ailerons becomes more effective at higher speeds, so this will not be a perfect mix setup. At full throttle, but low speed, for instance, it may still not fully counter the torque roll, and at full throttle, high speed, it may counter the torque roll just a bit too much. This is why it may be best to trim the mix for full throttle, high speed, and then just counter it a little bit manually with the aileron stick at full throttle, lower speeds.

---or just use a gyro like Dillzio says. =] I wish you happy flying either way.
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Old Sep 27, 2011, 09:59 PM
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Originally Posted by Dillzio View Post
Lol, have you seen the pictures?

That fuselage is pretty mangled! It reminds me of Sarah Jessica Parker's face with no make up on.
What, so it looks like a horse now?
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Old Sep 27, 2011, 11:08 PM
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brace's Avatar
Australia, NSW, Ashby
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Originally Posted by Dillzio View Post
Lol, have you seen the pictures?

That fuselage is pretty mangled! It reminds me of Sarah Jessica Parker's face with no make up on.
Oh yeah its bad but you would be surprised
Check out this mangled wreck but he rebuilt it and it did the rise from the ashes trick

http://www.rcgroups.com/forums/showt...163654&page=11
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Old Sep 28, 2011, 02:00 AM
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if someone has a clue how to do it a DYI post would be welcome.
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Old Sep 28, 2011, 06:12 AM
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Originally Posted by Melnic View Post
If you want really precise control in HH, I think your gonna need a mems type gyro. Again, I thnk you may need some trimming is all.
Thanks for the tip, just got myself a GY-100 for a good price online

Maximum rate range of 800 degrees/sec, that should do nicely on the funjet :-)
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Old Sep 28, 2011, 07:10 AM
Team Wack-a-Mole
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Maryland
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Funjet needs to be streamline, I agree, any broken parts from that pic needs replacing.
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Old Sep 28, 2011, 10:09 PM
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Old Sep 29, 2011, 03:23 AM
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Oh come on Chatch, you had to go there didn't you?
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