The biggest problem with extensions is that, after a time, if the connector is in a place not frequently mated/demated, corrosion slowly builds up and causes intermittent operation. It is always more reliable in those cases to solder in an extension.

Have you had a failure due to connector corrosion? I never have. I would expect to see this type of failures telegraphed with intermitent; or, "jittery" servo operation. Lets not forget that every channel in use, has to go through at least one of these types of connections at the receiver. Also, these terminals are generally plated with materials very resistant to corrosion and the locations the connections are contained in (the wing; or, fuselage) are not very caustic environments!

You want to solder these connections have at'r. But, as long as my connections stay connected, I think there is about the same amount of risk using either type of connection!

If that is a real concern for you, then use some dielectric grease like is used on spark plugs.

Servo extensions are much more expensive than cutting and lengthening the wire by soldering in additional wire.
If you don't know how to solder it is probably best to just pay the money and buy the extensions.
I have never had an issue with a servo extension plug oxidizing or corroding, I would think that if the environment created this issue it would not be localized to the mated connectors.
Here are examples of the three most common solder connections for inline wire splices.
If you search the internet on how to solder two wires together you will find many many examples that expouse twisting the wires together to create a mechanical connection and then applying solder to hold the joint in place, there are alot of reasons I don't like this method of making an inline wire splice. But this method is so prevalent and so many people believe this to be "the" way to do it that I am not going to debate it.
It will work fine but think about this, it creates a right angle stress point that will predictably fail the quickest in a pull test and more importantly to the RC application it creates a big bulky joint that is prone to snag when pulled through a model airplane. On the plus side it is probably the easiest connection to make since twisting the wires together creates a stable place to apply solder.
The wires soldered together using the hooked ends is technically the 'correct' way to make an inline splice, but for this to be effective correct tinning and bend radius has to be taken into account and again for RC applications it does not offer any significant advantage over the parallel wire splice.
The other example is the parallel connection. While there is no mechanical advantage of twisting or hooking the wires together, it creates the least bulky joint which allows the wire to most easily be pulled through a model airplane. It also creates the least stress angle that otherwise defines the break point of the other joint types in a pull test.

Which ever method you choose if you make the solder look like the solder in the pictures then you have applied the solder in the correct quantity and at the correct heat setting.
In the series of photos four wires (AWG 22) were soldered together using the three different solder joints to make one long wire spliced together with inline splices.
Pic #1 shows the three solder connections immediately after they were soldered together.
Pull pressure was applied to the two end wires stressing all three solder joints at the same time, the pressure was increased until the first joint failed and a photo was taken of the failed joint and the remaining two.
Pic #2 shows all three joints after enough pull pressure was applied to cause the first failure.
Note that the insulation is now pulled farther away from all the joints due to the copper stretching, so even the first joint that failed is a significantly strong joint.
Pull pressure was again applied until the next connection failed and a photo was taken.
Pic #3 shows two failed joints and the last remaining solder connection.
The copper is stretched even more which makes the insulation be even farther away from the soldered connection
Pull pressure was agin applied until the wire failed and a picture was taken.
Pic #4 shows all three failures, note that the wire broke before the last solder connection failed.

I had been trying to solder stuff for years, having a little luck with small joints like changing motors out in the pits. When trying bigger stuff, or atleast making them look nice and clean, I was always horrible at it. I thought the maybe God just didn't want me to solder. I eventually bought me a 35-100 W gun (has a trigger for extra heat) and I have been so happy with how it has worked. My dad's old irons from when I was in diapers were the problem I think.

Hey Brett just get you a big old blow torch and a stick of body lead. You can make anything look good

As to the question above, have you ever seen failures due to corrosion. The answer is an emphatic "YES" many times over. I've also seen where servos started glitching or show erratic behavior and, after demating and remating the connectors, the trouble disappeared. This was almost always traced to corrosion in the connectors, often so small as to be almost undetectable. The removal and re-engagement of the contact surfaces scrubbed off the corrosion. The current in the signal lead is so very small (microamperes) and the voltage so low that it takes very little corrosion to block the signal. If you are in an environment that occasionally has a high humidity, corrosion is an even greater problem than for those who live in an ideal climate. Even the gold plated ones can show this as the plating is very thin in most cases and not very durable. Even the poorest solder joints are usually a better risk. The solder pull test described above is not very pertinent, a solder joint is not noted for strength and should not be used for such. It is made for electrical continuity under normal conditions encountered in the field where tensile strength has little application.

I did use a mini torch once, it worked!

I watched a guy do the lead bodywork at a kustom kemp show in KS, he was amazing!

I've a friend who commented that he couldn't solder.

So I was going to show him

His soldering iron wouldn't heat up.

Some other day?

If that doesn't give a "cold" joint, nothing will.

I have an idea, here Rodney! You solder your joints and then all you'll have to wory about is the connection at the receiver. I won't solder my joints; but, I will use extensions and I won't worry about the two extra connections, or all the connections at the receiver!

Works for me, buddy, does it work for you?

The nice thing about the connections at the receiver, they get unplugged and re inserted ever so often which tends to correct the minor corrosion problems before they become major ones. On my smaller planes I am not so particular, on the ones that cost a lot, I take much more care so none of my quarter scale jobs have extensions.

I fully concur with Rodney, corrosion on inaccessable extensions especially when there is an excessive number of plugs is a very common problem indeed. Some of the rats nests of extensions that folks bring to me complaining of glitchs is shocking even on simple airplane installations.
I have never failed in clearing that kind of problem up just by cleaning up the installation and eliminating excessive wire and plugs. If you don,t know how to solder its time to learn and acquire the appropriate tools to do so.

With the recent avaliability of a number of different P-38 and P-61 ARF's which are an extreme challange in the wiring system because of the placement of the servos, batterys and rx scattered in three different fuselage's if you will. Attempts to use extensions will result in a horrendous mess of plugs and wire. With these types of airplanes the need for a custom soldered harness soon becomes quite evident. I have both a P-61 and a P-38 arf on my bench right now friends have purchased second hand in one case third party. In each case the the orginal assemblers could not deal with the harness except by stacking extrension on extension.

John

I understand in big complex airplanes using a custom harness, but I would think that if I have to run a couple extensions to the back of the fuse, some dielectric grease and a good clip should keep the connection from ever needing to be messed with again.

Perhaps Brett in the simple configuration on a fuselage thats fine. However even in simple airplanes and it really is not even related to size with the ever increasing popularity of wing servos (and thats great) There is always the associated problems of the extensions of the wing servos with buried inaccessable plugs and even the difficulty of just pulling the plugs through or partially into the wings.

Adding more plugs than neccessary will increase resistance no matter what grease you use as opposed to a single run of proper Length wire and thats something I care not to do. So even on the small simple ones that have any wing servos (aileron, flap, throttle or gear) I cut the new servo lead in half and add (usually heavier servo wire agine for less resistance) that will give me the perfect length at the fuselage joint to connect to a short extension to the Rx. Only one plug for airplane assembly purposes and no more or excessive lengths at fuselage/wing joint to be wadded up during each assembly.

John

Oh oh, now there's two of you! Soldering is absolutly no problem for me and I would do it if I felt it was necessary!

Are you guys doing this unplugging and replugging at the receiver as a periodic maintenance proceedure? I put the radio in the airplane and it doesn't get touched again until I either crash or pull the radio out to do something else with. I look the radio and everything over very regularly; but, do not disconnect any of the wiring.

You guys are absolutly insistant that your way of doing things is the correct way to do them, arn't you. I am a maintenance freak also. I take care of my planes and check them over far better then most people here at R/CU, before I fly and at regular maintenance checks. Had I ever found what you feel to be a problem with my extensions, I would be taking action to remedy! The problem you feel so strongly about has not happened to me since I started using extensions and Y-connectors in the early 1980s. Obviously, you feel this can be problem and I can understand and respect you opinion! However, I am just not seeing this as being an issue!

This is what happens when someone spends to much time at the warzone, the AMA forum at RCU which is relatively unmoderated and every post is combative for no reason. It spills out to the rest of the forums and is especially unbecoming in the beginners forum. Agine only just my opinion.

I expressed my simple opinion on the subject matter in two posts in a civil and cohesive manner so will not pursue this thread any further, I have no need to dominate.

John

Wow, I take exception to your opinions, defend my position, and I spoke civilly to both of you! I don't have wargames and I stay away from the AMA Forum as I feel it's a waste of my breath.

You guys are telling me my opinion is wrong and I have every right to defend myself!

I ended my reply respectfully with: "Obviously, you feel this can be a problem and I can understand and respect your opinion! However, I am just not seeing this as being an issue!" and then I am termed "combative"!

Yes, this is a beginners forum and you guys are telling beginners they must solder their ailerons leads and not use extensions! Is this helping them out?

As one who made a living trouble shooting and doing failure analysis on electronics, mostly instrumentation, I have to agree with John emphatically. It is hard to argue with years of data proving the reliability of solder joints and crimped joints over connectors. There is overwelming statistical evidence of better reliability when crimped or soldered/welded connections are use in liu of the type of connectors used in most RC. Of course what I worked on demanded 100% reliability as human life was often at stake if a failure occured.

Well Rodney, I guess my having been involved with the R/C hobby since 1968, without a corroded-bad connection failure and having worked as a Marine Surveyor and exposed to corrosion problems on many levels, my experience, is simply trumped by your experience! You know what's stupid about this whole disagreement? I will conscede that soldering is the very best method of extending servo leads. However, I simply disagree that the method is absolutly necessary and I feel it's recommendation to beginners is adding complications, they simply do not need.

Now, if you'll excuse me I'm going to make like a JohnBuckner and have no need to dominate! You win Rodney ol'Buddy!! Good for you!