26 gauge servo wires are becoming more and more common. Has anyone seen any good info as to when its okay to use 26awg servo extensions. I was wondering if they are okay to use on things like ailerons and elevators on say 40 to 60 size planes (if anyone remembers what 40 size means :). Higher torgue / faster servos draw more amps. Thinner wire means more voltage drop. Longer extensions means more voltage drop. More voltage drop to the servo means lower operating voltage of the servo so reduced power. Maybe worse ?
I only use the skinny stuff if weight is an issue.
Otherwise I use heavier gauge to reduce voltage drops.
Whatever you use try to keep them as short as possible.
Pat MacKenzie
"Whatever you use try to keep them as short as possible.
Pat MacKenzie"
This sounds like rolling making your own...servo extensions that is. Does anybody do this? Any tips for those considering doing this?
I do it several ways, depending on what sort of model it is and how much time I have ;)
- pick extensions that are the correct length
- cut the servo lead and splice in a length of wire
- put a new wire on the servo right from the PCB and crimp on a new connector.
- and for the indoor planes possibly replace all the wires with enameled copper and solder them right to the receiver.
http://static.rcgroups.net/forums/attachments/1/4/1/9/9/a1557136-188-rcvr.jpg?d=1194216851 (http://static.rcgroups.net/forums/attachments/1/4/1/9/9/a1557136-188-rcvr.jpg?d=1194216851)
If you are planning on making your own then buy a crimping tool.
Pat,
I think the crimper may be the missing puzzle part for me. Is this something specific to RC or common to electronics? Where should I look to buy one? I ''ve bought some HK servo terminal kits but the metal contacts need to be crimped after the servo extension is cut to the correct length. I don't think pliers would do this well especially with micro connectors.
Any advice on crimpers appreciated
Although I like Pat's suggestions for doing it the best way, I almost always extend my servo wires (for wing servos, etc) by buying a roll of servo wire (usually the thicker stuff these days and it's usually only on the larger planes I'd need to extend), cutting the servo lead in half, and splicing in the required extended length. That way I don't have to disassemble the servo or mess with the connector. I just insulate the individual solder joins with small diameter shrink tubing.
Lately, I've been a bit lazier when building ARFs and just buy an extension and plug it in, but it always bugs me a bit to have so many connectors in-line in the wings.
Robert
That was the second method on my list ;D
Back when extensions were expensive it was by far the most common method I used.
Now they are so cheap bought from HK that I get lazy. :)
I generally use heat shrink on each joint and add another one around them all to act as a strain relief
HK sells a crimper, a bit different than the one I have.
http://www.hobbyking.com/hobbyking/store/__13446__Hobbyking_Electrical_Connector_Crimping_Tool.html (http://www.hobbyking.com/hobbyking/store/__13446__Hobbyking_Electrical_Connector_Crimping_Tool.html)
Theirs looks like it does both the electrical connection and the insulation griper in one go. I have to do them separately with mine.
I have bought a lot of pwm connectors, wire and tools from www.hansenhobbies.com (http://www.hansenhobbies.com) over the years for a highschool robotics program. Good stuff, good support. Digikey sells connectors, headers too.
Hobby king actually had in stock most of the 22g extensions I needed (for once) so I bought a pile.
In my experience, I will caution that unless you are very confident that your vision, your tiny wire stripping skills and tiny pin alignment and crimping skills (and possibly pcb soldering skills) will not put your expensive plane at risk, the average person should just buy an extension. One undetected slight nick of the copper servo wire while stripping it could lead to the wire that fractures or becomes intermittent under vibration at the worst possible time. Fortunately it was not a plane :)
Pat, Dave,
Thanks for the help. Friendly help is one of the best parts of TEMAC!