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Archive for July, 2011
Posted by rcbirk21 | Jul 30, 2011 @ 01:34 PM | 17,544 Views
Ben's words of wisdom when it comes to servo setup:

1.Servos break, they're servos, so yes someone could have a bad servo. Take your linkages off and move the servos and try to resist them with your hands. A weak one is pretty obvious.

2.Make sure your surfaces move smoothly. This really means "If you are having problems with your rudder, fix your tailwheel, it's causing drag and overworking your servo".

3.Make sure your servo arm is not too long. Most arms have several holes for exactly this reason, and drill bits work every time they are tried. You want 30 degrees on ailerons, 45 degrees on elevator (rudder is not as critical, 40 degrees or anything close) while you have MAXIMUM endpoint on the Tx on that channel.

We fix dozens of setups at fly-ins every year. The above suggestions take care of the servos. Just for thoroughness, here's the other things we fix:

4.Put 75% expo (in the correct direction! Negative on Hitec and Futaba, positive on JR and spektrum) on all surfaces.

5.Make sure the elevator servo doesn't have sloppy gears.

6.Make sure it's not a HobbyKing prop.

7.Take off, trim the elevator and rudder for it to fly straight.

8.Roll it inverted, if it climbs or dives move the battery to compensate.


If you look at the specs on any servo, youhave the torque in oz/in, but most installation are compromised, resulting in this torque being reduced. You can really easily tell how bad a particular install is killing torque by looking at the endpoint adjustment on the Tx.

To be "Right", the endpoint should be maxed out. On my Tx, that's 140% on the ATV (servo travel or endpoint) adjustment.

If my servo arm is too long, I can't use the full 140%, I have to turn it down. Every bit it is turned down is reducing the effective torque of the servo. On my setup, on 4S, I can be compromised down to about 115-120% before I start noticing. At 100%, I can definitely feel it.
Posted by rcbirk21 | Jul 20, 2011 @ 08:02 PM | 17,624 Views
104 battery strap (1 min 7 sec)