Questions and Answers If you have general RC questions or answers discuss it here.

Testing wrecked servos

Reply

Old 10-05-2006, 04:06 PM
  #1  
RVM
Senior Member
Thread Starter
 
Join Date: Mar 2006
Location: Sacramento, CA
Posts: 1,977
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Testing wrecked servos

I recently crashed a plane and was wondering how to go about making sure the servos are still reliable. The airframe was destroyed (bad enough to shatter spruce spars). I had JR DS811 servos throughout, except for the rudder/tailwheel, which had a DS821.

The servos for the tail section should be fine, as this was a nosefirst attempt to get to China via the shortest route (at least it was moderately soft dirt and not concrete), but the wing servos (4 of them), especially the two inboard servos, seemed to take a pounding. It broke one of the DuBro HD servo arms, and bent up the 4-40 steel rods.

I grabbed a few of the servos and hooked them up. They sound fine, and when I put a load on them, they don't move. I can stop the servo arm completely and the servos just buzz away with no slipping.

Is there anything else I can do to be sure these servos will still operate accurately and safely? Should the potentiometers and the other sensitive electronics still be ok? I don't want to risk another plane due to servo failure, or even worse, risk the chance of hurting myself or another person.

Thanks!
RVM is offline  
Reply With Quote
Old 10-05-2006, 04:27 PM
  #2  
aerowoof
 
Join Date: Jun 2006
Location: pembroke, NH
Posts: 2,952
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Testing wrecked servos

usually it is the gears that strip in a crash or the servo case itself .if the servo's are working then the electronics should be okay.you should be able to remove the top cover to inspect or even replace the gear set.if there is any doubt just send them in for service,the cost will be minimal versus the cost of plane engine and whatever it may hit if something did go wrong.
aerowoof is offline  
Reply With Quote
Old 10-06-2006, 12:22 PM
  #3  
jaka
 
Join Date: Dec 2001
Location: Upplands Vasby, SWEDEN
Posts: 7,790
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Testing wrecked servos

Hi!
Take the servos apart and have a look if in doubt ! It's very simple and easy to do.
There is always 4 gears in all servos and the gears can only be placed at one place, so you can't do anything wrong.
jaka is offline  
Reply With Quote
Old 10-06-2006, 12:31 PM
  #4  
RVM
Senior Member
Thread Starter
 
Join Date: Mar 2006
Location: Sacramento, CA
Posts: 1,977
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Testing wrecked servos

I'm going to take them apart and visually inspect the gears.

Thanks!
RVM is offline  
Reply With Quote
Old 10-06-2006, 04:10 PM
  #5  
BillS
Senior Member
 
Join Date: Sep 2004
Location: Greensboro, NC
Posts: 3,312
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Testing wrecked servos

After gear inspection sometimes I will mount the servos to the table and lift a weight off the floor. I move the weight through the entire range of servo travel.

Bill
BillS is offline  
Reply With Quote
Old 10-06-2006, 04:11 PM
  #6  
RVM
Senior Member
Thread Starter
 
Join Date: Mar 2006
Location: Sacramento, CA
Posts: 1,977
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Testing wrecked servos

I just grabbed the servo arm and held it still while moving the sticks. The motor whined about it, but no slipping. Not sure how good that is for the servo, but I just did it enough to see if the gears would slip.

ORIGINAL: BillS

After gear inspection sometimes I will mount the servos to the table and lift a weight off the floor. I move the weight through the entire range of servo travel.

Bill
RVM is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service