I am building a Balsa USA Bristol M1 and want to build my own servo extensions. I am wondering if #22 wire is heavy enough for these extentions. The commercial extentions appear to be of larger wire. I will be using Futuba S3004 servos and the extentions will be approximately 24-27 inches.

Thanks,

Hud

The pro series heavy-duty extensions are made with 20 gauge wire.
24" is $6.99 and 36" is $7.99
At that price why make them?
tw

Some people prefer to make them so they don't have the connector in the middle to come undone. I just use heat shrink tubing on extensions and have no problems. I'm not a big fan of cutting the servo lead to lengthen it, which means having to remove the extension to put it in a plane that doesnt' need the extension further down the road.

Hogflyer

that length of extension,I would use a heavier gauge wire,also be aware that you could be picking up rf noisde at that length which could result in radio glithes

Hud-n-OTOW,

After thinking about this a bit - the BUSA Bristol M1 is not a speed demon by any sorts. If I remember correctlly, the wing is a one piece wing (at lest is should be with a 60" span). And with the undercambered airfoil it's not a speed demon by any sorts. If you mount aileron servo's they will be way out towards the tips. On a plane like this, you may find it easier to mount the aileron servo in the center of the wing and run stiff push rods out to bell cranks which are hooked to the ailerons. This has been done for the past 60+ years. For the elevator/rudder, don't mount them at the tail, just run long pushrods made from 1/4" hardwood or dowels direct from the servo to the control surfaces. If you need any extension, it would probably be a 6" between the receiver and the aileron servo.

Hogflyer

I have made my own in the past or you can send them to radio south and ask for custom lengths to be installed.
They will do it for a little more than the price of an extension.

I'm with Hogflyer here. I prefer to solder in my own extensions for just this reason. Every connection point in a wire is another possible failure point. I try to eliminate as many of these connections as I can. But I will say this, if you're not 100% sure that you have good soldering skills then I would stay away from trying to make your own extensions. A poor solder joint is more dangerous than anything.

Ken

if you're not 100% sure that you have good soldering skills then I would stay away from trying to make your own extensions. A poor solder joint is more dangerous than anything.

That was my point, just better worded, on why make them.
I'm an electrician and I don't make my own extensions.
I use heat shrink to hold the servo ends together.
tw

If you do solder regardless of your skill, the joint can't be in a position that it can flex. If through flying and handling, teh solder joint can flex, this WILL be a point of failure.

I strongly suggest using HD wire for extensions over 12" in length.

You get a minor voltage drop with longer extensions. The heavier guage wire will minimize the voltage drop. On a slow flying plane with standard servos it probably will not make much difference, but if you are using high power servos (digital types especially ) and/or on a fast plane the heavier guage can make a difference.

If you are making your own, the difference in wire cost is almost non existant, if you buy them premade, the difference in cost (to me anyway ) is worth the piece of mind.

i've used 22 ga wire for extensions up to 18 inches in length and haven't had any issues so far, i use heat shrink tubing over each wire and then another piece over all three - this helps with the issues of the joint flexing and becoming unstable.

also, should you go the solder route....i suggest plenty of practice on scrap wire before you tackle the acutal joint. i've been an electrician/machinist/maintenance worker for 15+ years and i still make at least one practice joint before i solder the actual joint together (i guess old habits die hard) LOL

White Knight Wing Protectors makes all sorts of HD 20 gauge ext cables. They are half as expensive as Hobbico's HD, sevice is pretty good too.
I'll add thier web address to this post when I get home in the morning.