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ELEV-8 kit nearly ready to fly — Parallax Forums

ELEV-8 kit nearly ready to fly

David BetzDavid Betz Posts: 14,516
edited 2012-05-25 18:07 in Robotics
I got my receiver cable situation resolved by taking Ken's suggestion and sanding down the corners of the connectors. I updated the firmware on the HoverflySPORT board and got it working with the radio and verified that the propellers are spinning in the right directions. The only thing I have left to do before trying to fly it is to fasten the receiver and battery. I can fasten the receiver with tie-wraps but I'm looking for a good way to fasten the battery that makes it easy to swap batteries. What is a good way to mount a battery so that it can easily be swapped? I've ended up placing my battery below the HoverflySPORT board.

Comments

  • W9GFOW9GFO Posts: 4,010
    edited 2012-05-17 21:02
    Good question. I have my battery mounted underneath as well. Rather than swapping batteries I just charge it in place.
  • David BetzDavid Betz Posts: 14,516
    edited 2012-05-17 21:11
    W9GFO wrote: »
    Good question. I have my battery mounted underneath as well. Rather than swapping batteries I just charge it in place.
    But I bought two batteries so I could have more flying time. I'd like to be able to swap after one dies. :-)
  • Ken GraceyKen Gracey Posts: 7,392
    edited 2012-05-17 22:21
    David, this is really exciting progress. I think you're using a DX-6 transmitter, right? If so, start with the gain at 26% on the landing gear.

    And start your first flights on an area where you are surrounded by soft grass. Ideally, you'd have a low-cut golf course putting green about a few feet of diameter - very level - and grass about 6-12" tall around to soften landings. Just start to hover gently, and don't freak out when it's actually in the air. Lots of pilots either launch it into the atmosphere or let it slam to the ground. Don't be nervous - we can replace/repair any parts on this rig easily. It truly flies beautifully once you get a feel for the controls.

    Ken Gracey
  • David BetzDavid Betz Posts: 14,516
    edited 2012-05-18 05:40
    Ken Gracey wrote: »
    David, this is really exciting progress. I think you're using a DX-6 transmitter, right? If so, start with the gain at 26% on the landing gear.

    And start your first flights on an area where you are surrounded by soft grass. Ideally, you'd have a low-cut golf course putting green about a few feet of diameter - very level - and grass about 6-12" tall around to soften landings. Just start to hover gently, and don't freak out when it's actually in the air. Lots of pilots either launch it into the atmosphere or let it slam to the ground. Don't be nervous - we can replace/repair any parts on this rig easily. It truly flies beautifully once you get a feel for the controls.

    Ken Gracey
    Actually, I have the DX7s transmitter but I guess the settings may be similar. I'll try 26% to start. I'll try to make a video of one of my first attempts to fly it.
  • David BetzDavid Betz Posts: 14,516
    edited 2012-05-21 06:22
    Well, I made my first attempt at flying my ELEV-8 without a lot of success. It seems to veer off in one direction almost as soon as it gets airborne. I may have the gain settings wrong though. I have a Spektrum DX7s and the gear settings are 100-0 for the off position and 0-100 for the on position. The Hoverfly manual suggests -25 and 25 so I figured that mapped to 25 on both settings. This seems to result in the graphic indicator on the transmitter moving from a little left of center to a little right of center when I flip the switch which should be the same as -25 to 25. Does anyone else have this transmitter? What settings are you using?

    Anyway, at the moment I'm grounded since one of my attempts resulted in the ELEV-8 flipping over and breaking two of the propellers. I have a crash kit so I can get flying again but I'd like to come up with some theory as to why I'm having so much trouble controlling it before I risk any more propellers.
  • dmagnusdmagnus Posts: 271
    edited 2012-05-21 07:37
    David, it sounds like the same problem I was having. As soon as I turned on autolevel (gear switch), it would do a perfect flip onto it's side (to the left). I have a DX8 and had the gains set all wrong. You definitely have too much if you are at 100. I would try 25 on both sides. Be sure to be in the softest grass you can be.
    I also found early on that I had a couple of the connections wrong. Carefully go through and make sure your ESC's are attached to the proper "legs" (I had one wrong - oops) and that caused an immediate flip as soon as I tried to take off - with the gear switch in the "normal" position. I would have sworn they were right, but after practically taking the whole thing apart, I found some problems.
    Also carefully look at the connections to the board from the ESC's. I had my gear in the wrong place - really messed things up.
  • ratronicratronic Posts: 1,451
    edited 2012-05-21 07:39
    David I can't comment on the setting the gain for the gear channel on that transmitter, but as far as testing the response of the quad I hold it by hand (VERY carefully with a FIRM grip) at the top then with the other hand slowly raise the throttle until it feels like it is giving some lift, then while holding a little above where you started it should feel like it just wants to float there but if you rock it right, left and front, back you should feel it resist you. This next part is just a beginner's (still a beginner) experience. I used a pocket level on the top of the craft from side to side and front to back. It seems to me the more earth level the craft is before you take off the less correction you have to deal with the aileron/elevator sticks to acheive hoover.

    Edit: Slowly raise the throttle the first time while holding if there is a problem with your settup (it wants to lean a particular direction) then throttle down and find your problem. Also make sure the trims on the sticks are all zeroed.
  • David BetzDavid Betz Posts: 14,516
    edited 2012-05-21 12:14
    Here is a video of my first attempts to fly my ELEV-8 kit. I guess I need a more open area to fly in.

    http://www.youtube.com/watch?v=W_UJtbGraAg&sns=em
  • dmagnusdmagnus Posts: 271
    edited 2012-05-21 12:33
    David, it looks like you've got a TON of right rudder trim in. It wants to spin clockwise. Check that first. Also I noticed that you aren't orienting yourself to the quad before you start. The red legs should be facing "forward", with the black ones toward you. That way you should also be able to see the lights on the board. More importantly, you are attempting to fly in the most comfortable and intuitive way - facing the direction of travel. When the quad is oriented left, right or backwards to you, your trying to overcome the much harder orientation factors. Coming "toward" you (red facing you), your control inputs are opposite (right is left, etc.) That just makes it all the more difficult to control at first.
  • W9GFOW9GFO Posts: 4,010
    edited 2012-05-21 12:55
    I'm noticing that sometimes it yaws left and other times to the right. That leads me to believe that you are unintentionally moving the rudder when controlling the throttle.
  • David BetzDavid Betz Posts: 14,516
    edited 2012-05-21 13:20
    W9GFO wrote: »
    I'm noticing that sometimes it yaws left and other times to the right. That leads me to believe that you are unintentionally moving the rudder when controlling the throttle.
    That is very likely. I've never flown an R/C plane or copter before. Should I get an easier vehicle to practice with before graduating to the ELEV-8?
  • W9GFOW9GFO Posts: 4,010
    edited 2012-05-21 13:43
    I would recommend a simulator before another RC vehicle.

    Less recommended is to make your rudder less sensitive. Add some expo to it in the TX.
  • ratronicratronic Posts: 1,451
    edited 2012-05-21 14:00
    I use RealFlight 6 which includes a quad that is harder to fly than the Elev-8, but at least the crashes are easier on your wallet.
  • BRBR Posts: 92
    edited 2012-05-21 18:00
    David,
    My first couple attempts to fly looked much like your video. The problem turned out to be swapped cables on the ESC side of the hover fly. I strongly recommend double-checking the connections. It shouldn't be anywhere near that difficult to control if everything is correct.

    BR
  • David BetzDavid Betz Posts: 14,516
    edited 2012-05-21 18:56
    BR wrote: »
    David,
    My first couple attempts to fly looked much like your video. The problem turned out to be swapped cables on the ESC side of the hover fly. I strongly recommend double-checking the connections. It shouldn't be anywhere near that difficult to control if everything is correct.

    BR
    I verified that my motors are wired correctly by running a program written for me by ratronic. Thanks!!!

    Unfortunately, that means that swapped cables are not the source of my problems. Maybe I need to buy the RealFlight 6 simulator and practice.
  • David BetzDavid Betz Posts: 14,516
    edited 2012-05-21 19:00
    Ugh. I have found my current most serious problem. I must have bent the shaft on one of my motors because it doesn't spin freely when not powered. I don't see anything obviously wrong with it but something is binding it up. It looks like I won't be able to make another flying attempt until I replace the motor.
  • W9GFOW9GFO Posts: 4,010
    edited 2012-05-21 21:20
    Try removing and replacing the motor shaft. Sometimes just doing that fixes the problem. If not, look in the parts that came with your motors, maybe you have a spare shaft in there?
  • ercoerco Posts: 20,256
    edited 2012-05-21 22:28
    Is it just me, or does that 2-year-old Hexacopter seem even more amazing now that we see that these things are getting cheaper, but still not easy for Joe Average to fly? That thing seems incredibly stable.

    http://www.youtube.com/watch?v=fyYujjP5J-k
  • Ken GraceyKen Gracey Posts: 7,392
    edited 2012-05-21 23:22
    David Betz wrote: »
    Ugh. I have found my current most serious problem. I must have bent the shaft on one of my motors because it doesn't spin freely when not powered. I don't see anything obviously wrong with it but something is binding it up. It looks like I won't be able to make another flying attempt until I replace the motor.

    I can send you another one. Let me know what else you need via e-mail and we'll get you back in the air by the weekend.

    You might need to crash and burn a bit before you fly. . . or get a simulator.
  • Cluso99Cluso99 Posts: 18,069
    edited 2012-05-22 01:03
    Are you sure you have 2 counter rotating props? It is doing what my quad did before I received my c-r props.
  • David BetzDavid Betz Posts: 14,516
    edited 2012-05-22 03:34
    Cluso99 wrote: »
    Are you sure you have 2 counter rotating props? It is doing what my quad did before I received my c-r props.
    Yes, two are marked "P" which I guess stands for "push". I've also verified that they rotate in the correct directions and that they all push air out the bottom when spinning.
  • David BetzDavid Betz Posts: 14,516
    edited 2012-05-22 04:36
    W9GFO wrote: »
    Try removing and replacing the motor shaft. Sometimes just doing that fixes the problem. If not, look in the parts that came with your motors, maybe you have a spare shaft in there?
    I removed the rotating part of the motor with the shaft in the middle but I can't figure out how to remove the shaft itself. I've removed both of the set screws but the shaft doesn't come out. Do I have to use force to remove it? Also, the spring clip that holds the rotor and shaft in place got bent when I removed it and I don't see a spare in my motor repair kit. The good news is that I do have a new shaft that I can use if I can figure out how to remove the old one.
  • David BetzDavid Betz Posts: 14,516
    edited 2012-05-22 05:24
    David Betz wrote: »
    I removed the rotating part of the motor with the shaft in the middle but I can't figure out how to remove the shaft itself. I've removed both of the set screws but the shaft doesn't come out. Do I have to use force to remove it? Also, the spring clip that holds the rotor and shaft in place got bent when I removed it and I don't see a spare in my motor repair kit. The good news is that I do have a new shaft that I can use if I can figure out how to remove the old one.
    After trying to get the shaft out of the magnet assembly I tried putting the entire thing back together and as W9GFO suggested, it now spins freely! So I guess I don't need to know how to replace the shaft right away. I just need to figure out how to put the spring clip back in. I found that I have a spare to replace the one I bent when removing the shaft and magnet assembly but I'm not sure how to install it. Is there some special tool to install these clips?
  • David BetzDavid Betz Posts: 14,516
    edited 2012-05-22 05:59
    Ken Gracey wrote: »
    I can send you another one. Let me know what else you need via e-mail and we'll get you back in the air by the weekend.

    You might need to crash and burn a bit before you fly. . . or get a simulator.
    Hi Ken! Thanks for offering to send a new motor but I don't mind buying my own replacement. After all, I'm the one who broke it! I looked at the HobbyKing site for Turnigy 2217 20turn 860kv 22A Outrunner which I believe is the motor that the ELEV-8 uses and found this:

    http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=5691

    This looks the same as the ones that came with my kit but is a different color. I'm assuming that is all that is different and that this would be an adequate replacement for the one I broke, right?

    Also, I think I may spring for a simulator to avoid these expensive learning experiences! :-)
  • David BetzDavid Betz Posts: 14,516
    edited 2012-05-25 13:49
    David Betz wrote: »
    After trying to get the shaft out of the magnet assembly I tried putting the entire thing back together and as W9GFO suggested, it now spins freely! So I guess I don't need to know how to replace the shaft right away. I just need to figure out how to put the spring clip back in. I found that I have a spare to replace the one I bent when removing the shaft and magnet assembly but I'm not sure how to install it. Is there some special tool to install these clips?
    I guess I spoke too soon. While the motor does spin more freely than it did before I took it apart, it is still stiffer than the other three. I guess I should try replacing the shaft. I have a replacement one but I can't figure out how to remove the bent one. It certainly doesn't just slide right out. Should I have to use a lot of force to get it out?
  • W9GFOW9GFO Posts: 4,010
    edited 2012-05-25 14:47
    It's been a few months since I removed a shaft so I cannot say with absolute certainty but I do believe it took a lot of force and twisting to get it out. Yeah, I also think I remember that another motor's shaft came out quite easily. They are not all exactly the same fit.

    When you put the shaft back in try to keep track of where the flats are so that they line up with the set screw holes. Make a mark with a Sharpie or something on the shaft.

    Those little clips can be tricky. Needle-nose, small flat blade screw driver and tweezers may be useful. Once you get them on use the needle-nose to squeeze them closed a bit more. Also, don't forget the bronze(?) thrust washers that go on before the clip.
  • SRLMSRLM Posts: 5,045
    edited 2012-05-25 18:07
    David Betz wrote: »
    Hi Ken! Thanks for offering to send a new motor but I don't mind buying my own replacement. After all, I'm the one who broke it! I looked at the HobbyKing site for Turnigy 2217 20turn 860kv 22A Outrunner which I believe is the motor that the ELEV-8 uses and found this:

    http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=5691

    This looks the same as the ones that came with my kit but is a different color. I'm assuming that is all that is different and that this would be an adequate replacement for the one I broke, right?

    Also, I think I may spring for a simulator to avoid these expensive learning experiences! :-)

    I don't think those are the same motors, although I can't find the original page for the red version anymore. IIRC, the red version has a higher Kv rating (so the blacks are actually better for quads).

    But then again, the reds that I ordered in December are listed as 860Kv on my invoice, so it may be the same as the black. Do you want to be the test guinea pig and buy one to compare?

    If they do have different Kv ratings then they won't be compatible. You can't mix and match.
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