Battery damage or servo?
 

HI all. I'm happy to have my new wing installed in my SlowPoke Sport 40. It went down hard in the fall. After having everything reassembled the other night i used my field charger to charge for speed. Was moving all my controls around seeing if everything was working ok. I thought maybe my elevator was sluggish. then in about two min. of moving surfaces my receiver battery was completely dead! Plane has sat for a few months uncharged. Maybe unwise to field charge it? put a battery on a wall charger and changed plane battery the following evening. Tested surfaces again, battery seems to be holding up fine, put my meter on for a load to drain it again, took quite a while to come down.Makes me wonder if battery was damaged from crash? Maybe it wasn't pilot error( crash ), could have had enough power for range test, then take off but not enough for complete flight + a dead stick in the sun.Ailerons and rudder move way faster then elevator or mabe it was always like that? maybe binding or bad servo?Hmm think I'm going to the basement to check for binding. Opinions appreciated thanks.

RE: Battery damage or servo?
 

Hi Brent0609,
Sounds to me like a bad servo. Also you might want to cycle your battery a few times to insure it's working properly. The other thing I would do is plug a good servo into your elevator channel and check the receiver to be sure it is OK.

RE: Battery damage or servo?
 

Disconnect pushrod from elev servo and see if it speeds up. While pushrod is disconnected would be a good time to check for binding too. IMO you would be better off using wall-wart to charge battery whenever you can but especially after such a long time. Charge battery pack and if possible check each sell as it runs down. Look for one cell that goes down too fast and may be bad. When in doubt - replace the battery as it is easier than repairing a plane.

RE: Battery damage or servo?
 

IF you are planning on staying in the hobby for a while you may want to consider buying something like a Super Test battery capacity tester. This is a less expensive alternative to a computerized charger that will tell you exactly how many milli amps you can get out of the battery pack before it needs to be recharged. BTW, I have compared the test results of the Super Test against a very expensive Cadex charger/analyzer that the hospital uses and the results are almost identical.[8D]

http://www.centralhobbies.com/Electr...rs/vltmtr.html

RE: Battery damage or servo?
 

I think culprit was your attempt at fast charging and your charger either false peaked (ie thought it sensed a full charge), or the battery just did not like the rate you fed it (some RX packs just don't like a fast charge). If you want to fast charge in the future you should experiment with the charge rate until you get resonable results, ie if your charger quits after a few minutes, the battery is full or it has false peaked, depending on the condition the battery was connected.

Probably best to use the wall wart whenever possible though. Fast chargers look for the voltage depression that occurs when the battery is full and the current is converted into heat. The heat causes the voltage depression, so you are actually overcharging the battery each time very slightly. Also, a slow charge tends to balance the charge between the cells.

Having said this though, I also agree with the others think it would be wise to check the capacity of the battery by using a discharger, otherwise you won't know how much capacity is left. If the one suggested is too pricey, Futaba has one for $40.

Good luck!