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What to use for control inkages- Midwest 27% Extra 300

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Old 12-11-2013, 08:48 AM
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jester_s1
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Default What to use for control inkages- Midwest 27% Extra 300

I have the airframe, just bought the servos, so now I need to start putting it together. Servo mounts were already done back near the tail for the elevators, and the previous owner had simple 4-40 rods for a linkage. He used a pair of Sullivan golden rods for a rudder pull pull (never saw that before) and 4-40 rods for aileron linkages. I'm an IMAC beginner, but I want this thing to last. So what is the standard these days for tail and aileron linkages to be slop free, durable, and able to take the torque of these newer servos that didn't exist when this plane was first designed?
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Old 12-11-2013, 04:32 PM
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Jester, what type of control horns are used? Typically a good setup would be the
Hangar 9 titanium turnbuckles with a Dubro HD ball link at each end. I would also recommend aluminum servo arms. As for the rudder, I would use Kev cord that ACP sells.
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Old 12-11-2013, 07:39 PM
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I have the aluminum servo horns. Is Kevlar cord better than steel fishing leader? I have a roll of 60 pound plastic coated leader I was going to use.
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Old 12-12-2013, 02:41 PM
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Jester, I never use steel leader cable. For one it will tend to stretch. The other reasons are a bit suggestive, it's heavier then Kevlar and I just don't like running what could act as antennas next to elevator extensions. I know that there are a ton of guys who would argue that last point but I work with aircraft antennas of all sorts for a living and have seen things that can't be easily explained away. IMO it's better to just eliminate the possibility of an issue before it has an opportunity to develop.
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Old 12-12-2013, 07:01 PM
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I've heard that concern before too about interference. I've never heard that it stretches, but I'll take your word for it. The concern I've seen is abrasion resistance Steel leader is going to handle the occasional bump that planes get better, right?
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Old 12-13-2013, 02:54 PM
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The Kev cord that ACP sells is a nylon coated Kevlar cable so it will resist rubbing and abrasion just the same as your nylon coated steel. I actually think it is easier to work with. You will want to toss the crimps that come with it and substitute for 3/8" pieces of K&S aluminum tubing. Once crimped secure with some med CA and cover with shrink tube. I have never had to replace it and some airplanes have had several hundred flights on them before being sold.
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