Wing weighting

[John Ferrell]

I would put the weight at the tip. It should only be about an ounce to balance. Tape on washers with clear packing tape to balance and try. If that works out ok, slit the wing tip & epoxy the weights out of sight. 

The advantage of going to the tip for ballast is that you use about 1/3 as much and the spar is not carrying the load. 

There are probably more sophisticated tests, but I think if you can pull & push moderate corners (competition style) with out aileron input you are OK.  I don't get too uptight about tracking a full deflection loop, it is not in the schedule that way. Tune to "normal" operation for best results. 

I am sure not every one will agree though. 
John Ferrell    
http://DixieNC.US

  ----- Original Message ----- 
  From: Richard Strickland 
  To: NSRCA 
  Sent: Saturday, July 31, 2004 12:58 PM
  Subject: Wing weighting


  Gentlemen,

  I made a large error a few weeks ago and totaled the first Temptation. Got the second one done and had problems with the engine and it had to go back.  Wife had gone to California to help her Aunt move--So I'm home alone, have to come home after work to let the dog out and the field is too far away to practice after that with the old trusty OMS.  What to do--what to do....  Got to looking at the "totaled" airplane and started tacking pieces back together--got to thinking hmmm--this might actually become an airplane again--called Lee and asked him for some cores and a chin cowl--told him I had two weeks of guilt free building time and would he send a set.  Well, it was right before the Nats and it didn't happen--understandably.

  So I had this severely crunched left wing panel--really NOT salvageable--now with all kinds of foam voids--wing socket knocked loose and should have pitched it--but I didn't.  I did some judicious goobering (read HEAVY) of epoxy and foam as best I could, lined up the wing halves back in the shucks with the wing tube--weighted them, said a little prayer and let 'em set. Well, at least it started looking like a wing.  The socket was still a little wobbly and I still had to graft about 25% of the crunched nose of it on and again--probably should've pitched it.  But nooo.... I cut a couple lite-ply spars, cut grooves for them from the bottom side up to the socket sides and glued those in--back in the shucks. Still didn't like the rigidity--so I did a couple spars on the top with a contoured cross partial rib boxing the socket, grafted foam, resheeted as needed, blah, blah, yada, yada... Could have done a set in this time.  Got the new cores yesterday.

  Here's the Question:  Since I've added about 2.5-3 oz to the panel with the average about 30% out in span; would I add a similar amount of weight on the other at roughly the same spot or LESS weight toward the end?  You know--levers, arms and all that....  I'll fly it as is and see how it reacts.  You don't have to tell me that I need to build another panel--that's a given. Having an extra set of heavier panels around here in the spring wind may not necessarily be a bad thing. It started out at 10 lbs.-7ozs.

  Thanks,
              Richard
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