Here is a quick tip on making adjustable control rods from unthreaded wire. This is based on another hint that suggests using the wire from the small colored flags that you can get from Lowe's or Home Depot for about $7 per hundred. If you use them you have to make the control rods a fixed length which is hard to do and get the exact length you want the first time. It also limits your ability to make small adjustments to dial in the neutral position that can be done with threaded conectors or E/Z connectors. This hint offers an easy solution.
All you have to do is add an offset in the wire that can later be adjusted. I like to connect to the servo arm with a "Z" bend. They are easier to insert than a modified "Z'. Then use one width of the needle nose pliars gripping just after the first "Z" and make a horizontal 45 bend. Go one more width of the pliars and make an opposite direction 90. Then go one more width and make a second 45 back in the original direction. You should end up straight with the first section after the "Z". After that make the rest of the rod to length using a modified "Z" at the control horn. The modified "Z" is easier to insert for the second end. Simply grip it with needle nose, twist it a quarter turn, insert into the control horn and release. It will snap right into place.
If you need a small adjustment just unhook the wire at the modified "Z" and either tighten or loosen the offest bends as needed, then rehook. All 3 bends should be adjusted each time to keep it uniform.
I like to put the offset bends just after the servo for appearance sake.
It should look like:
Here is another application where I used this idea:
This ia an Old Speedster to which I have added ailerons. In this case I placed the offset bends near the horn which has a modified "Z" bend. If you grip the offset bend firmly you can twist the wire enough to disconnect without using tools. If you do use a tool the offset provides a convenient gripping position. This is now my preferred position for the offset as long as the wire can be reached easily.
Update:
Someone asked if they would straighten in use. I don't think so:
This is one of the push rods from the 60" flying wing that is hanging from it. It weighs 460 g. There is no hint of straigntening. If you use the flag wires they are very stiff and do not need any middle support. Mine are usually under 10" long.
Update:
Someone asked about my landing gear. I am going to do a detailed article but here is a picture. The whole set is made from one wire hanger:
Another quick tip:
I install my embedded servos at an angle so that I can get at the control arm screw. The arm end is just high enough to let a screw driver fit on the screw. The other end is fully embedded to minimize drag. The angle does not effect operation.
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