LimB design changes

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AIM
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LimB design changes

Post by AIM »

Well, for me and I suspect the rest of us northerners the season has drawn to a close. Quite frankly with my workload right now it's truly a relief for me. I ended the season with almost NOTHING left as far as flyable planes go. I have NO undamaged wings and many are unrepairable. I even smeared a couple of fuses. (and it's tough to smear a fence post)
In a nutshell. I'm in perfect position to start over with a fresh approach to a great LimB design.
My current fence post plane is a great flier and reasonably tough but the problem is that when I take even a semi hard hit I not only bust the wing but also rip my servo leads and antennas off resulting in my current inventory of about 6 receivers missing the antennas, and a coffee can of about 17 servos with sheared leads or stripped gears.

I need a new design!

Problem 1. When the wing and fuse seperate or get twisted to much I lose hardware.

Solution 1. permanately attach the two together or eliminate the fuse from the picture.

Problem 2. "see problem 1"

Solution 2. ????
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drewjet
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Post by drewjet »

I would suggest a flat bat for the fuse. With the fence post everything is on the outside and doesn't get protection. With a flat bat, everything is on the inside and is better protected.
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boiler
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Post by boiler »

The battery and radio can fit inside the phencepost in my case. I usually rig the wing servo to plug into a servo extention outside fo the phecnepost. If the wing separates, it unplugs with out damage most of the time. The servo wire runs under the wing to plug into the extension so it is protected from a direct hit. I've gone to hitech mg625 or mg645 servos in the wing. Haven't lost a gear since that change so the extra cost is worth it. The servo horns are also very heavy duty on those models. I don't like the tank inside a fuse as a cut line or other leak may be harder to detect and can do even more damage.
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boiler
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Post by boiler »

Oh, and I criss cross all the rubber bands. It helps keep the wing on when it gets twisted.
Hat Trick
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Post by Hat Trick »

I see guys put the reciever in the wing and then a lot of wires are vulnerable. Usea small reciever and put itn the fuse and the only wires vulnerable are the aileron wires. Like Bob said use an extension and make sure the junction can come apart if the wing seperates. I use a lot of rubber bands as I hate twisted or even worse seperated wings. I don't hink I had a wing come completely off all season. Lots of twisted ones though and they almost always keep flying. Make sure there is enough slack in the aileon wires to allow some twist before the wires come apart!
ZenManiac
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Post by ZenManiac »

As for your antenna-less recievers, has anyone tried these Image
from E Cubed R/C http://www.azarr.com/antennas.htm?

I have one on an electric plane w/o any problems, and it would be easy to embed into a wing (if your receiver's there) or goop it to the fencepost without much fear of damaging or detaching it from the receiver since it's a much smaller target.

There's some discussion of people's experience on RC Groups http://www.rcgroups.com/forums/showthread.php?t=232149, several comments of good results to limit-of-sight.

I also insert my receivers (Polk Seeker 6) into the post, like Hat with a servo extension to the aileron servo.
montague
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Post by montague »

I'm also in the "nothing but servo(s) in the wing" club. I find it helps with surviving hits, and it makes it easier and faster to swap wings during a contest, since most of the time the wing is what's damaged, while the fuse isn't. Having only the aileron servo(s) in the wing means less extra parts in each wing to have them 100% ready to go as spares, and no messing around moving RXs from plane to plane between heats.
midair02
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Post by midair02 »

To keep the wing from coming off, use hooks instead of dowels to hold the rubber bands. This way, the rubber bands won't slide off the ends. Mike makes some out of plastic and they fit completely around the fuselage. I cut some out, but I don't have any pictures of them. This should convey the idea of what you want though. The metal hooks work just fine, as long as they are not to tight on the bottom of the fuse.
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o1moregil
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Post by o1moregil »

forget the fuse, built you a flying wing.
the only thing bad about it is that if you get a hard hit you will have to replace the whole wing LOL, but they are easyer to built though
ZenManiac
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Post by ZenManiac »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by midair02</i>
<br />The metal hooks work just fine, as long as they are not to tight on the bottom of the fuse.
Image
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote"><font size="2">Yeah, and if you leave the notches in the bottom of the fencepost, you can find a convenient notch to lock the hook into one location.</font id="size2">
EK
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Post by EK »

Installing a pin in the front and rear of the wing and putting the 1st 2 rubberbands around the holddown dowel and pin have sure cut down on the damage to my wires. Laughed at the idea and used 14 rubberbands until I became frustrated with cut wires. Installed the pins, now use 8-10 rubberbands and have had good results. Less bands allows the wing to shift while providing a shock absorber resistance to the off center hit resulting in less wing damage to boot.
sgilkey
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Post by sgilkey »

We (Brian and Eric actually) had more instances of shifted wings leading to pulled battery and/or elev plugs this year than any previous year, so I think the proposal to move the Rx to the fuse is a good one! On some new builds, I found we were ripping out wing saddles like crazy, finally concluded we had used too much velcro, and the "industrial strength" variety at that. Too little velcro, the wing shifts, too much and the saddle is ripped out. Gotta find" Just right!"
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Splash 1
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Post by Splash 1 »

I have eliminated my wings coming off by using wire (coathanger) pushing the "strap" through the wing bending the hooks out and then banding around the fuz the wire down either side of the fuz keeps the wing straight too!
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