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  #11  
Old 10-17-2019, 01:58 PM
WingsOnWheels WingsOnWheels is offline
 
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Going from memory, I think Vans makes the point that it is just important to not have the CG aft of the hinge, since the ailerons are connected and aerodynamically balanced.

On the slip-fit tube idea, the blind rivets on the LE of the aileron will get in the way.

For the epoxy, mix in a little flox, that should solve most of the brittleness issues.
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  #12  
Old 10-17-2019, 03:24 PM
rvbuilder2002 rvbuilder2002 is offline
 
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Quote:
Originally Posted by Stewbronco View Post
Many thanks to all ! So I think if I read that correctly is to statically " balance the aileron " much like you would an elevator? Makes good sense Cheers. Stew
The ailerons design on the two seat RV's, if built per plans, does not result in an aileron that is 100% statically balanced. There is a lot of service history that indicates that that is not a problem. Even with the wide variation in balance caused by the different paint finishes that have been applied over the years.

Even with that being true, my recommendation would be to add balance weight to an aileron that has been modified from the standard plans configuration, to bring it back to an equivalent level of balance that an unmodified one has (I.E., make it the same as the one on the opposite wing).

The best way to do this would be to add the weight inside the balance pipe. That is the farthest fwd location possible, so it will allow for adding the least amount of additional weight possible.
If it were me, I would use a runny flox mixture with small sized shot. This should reliably stay together. Once added to the pipe, the pipe could be plugged and the aileron stood on end so that the mixture migrates to fill the entire I.D. of the pipe.
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  #13  
Old 10-17-2019, 09:22 PM
Stewbronco Stewbronco is offline
 
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Default Balance weight

Many thanks again to all ! I did some further reading and YES I think ailerons should be matched . To that end I intend to start with them on the plane and I bought a very accurate fishing scale and will use that to lift the heavy aileron from the trailing edge to level ( neutral) This should give a fairly accurate starting point for weight after I apply the moment arm difference.
As far as weight itself ... if a tube insert I was going to machine flutes or grooves to allow for blind rivets and adhesive BUT liking the epoxy / flow/lead shot idea better as I think I can with a little luck get a better spanwise distrubution of the needed weight . Will of course do all I can to clean inside tube ( acetone ?) and figure some way to block end for the actual pouring of expoxy as I would intend to open the ends after for inspection and would probably be a part of pre flight for a good long time . Again I appreciate all the insight. Cheers. Stew
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  #14  
Old 10-18-2019, 12:03 AM
rvbuilder2002 rvbuilder2002 is offline
 
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I personally wouldn't be concerned with adding the weight along the entire span. You will be adding a small percentage of the overall amount. Assuring that it stays put is much more important than distributing it evenly. That is why I suggested standing it on end while it cured.
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  #15  
Old 10-18-2019, 12:45 AM
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emsvitil emsvitil is offline
 
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Quote:
Originally Posted by rvbuilder2002 View Post
I personally wouldn't be concerned with adding the weight along the entire span. You will be adding a small percentage of the overall amount. Assuring that it stays put is much more important than distributing it evenly. That is why I suggested standing it on end while it cured.

Put the weight opposite the trim..........
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  #16  
Old 10-18-2019, 07:23 AM
Desert Rat Desert Rat is offline
 
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The epoxy/lead shot idea sounds like a good one, but if you proceed with the sleeve inside the existing balance pipe solution, there might be a simpler way than machining grooves to clear the existing pop rivets.

You can't possibly need more than a few ounces, so likely a thin walled tube is all you'd need. If you use one that matches the ID of the existing pipe, Why couldn't you just cut it to a length that gives you the additional weight you're shooting for, drill out a few of the existing pop rivets, slide your new sleeve in to the location you want the weight, match drill the new sleeve through the holes, then wet install it with a thin coat of epoxy and install new longer pop rivets through the whole thing?

Then stand back, say "that's not going anywhere" and forget about it.
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  #17  
Old 10-19-2019, 08:09 AM
Stewbronco Stewbronco is offline
 
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Default Balance

Thanks again for all the insight .Been " brainstorming " how to secure that weight and actually decided to do exactly what you suggested ! I always like a " belt and suspenders " approach . As to determining the exact weight I thought I would 100% static balance both ailerons off the airplane individually with " temporary " weight inserted into the tube . The difference in the weight between the two will be the amount that permanently gets added to the " heavy" aileron as above .No permanent weight for the lighter of the two ailerons ( one without the trim tab ) Surely open to anything easier but this seems fairly easy and should be accurate.
I am new to RV's ,not the builder and not at home right now .. so no access to the actual plane or plans ,so forgive a very basic question but assuming that tube is aluminum? Want to be sure and get same material for the "insert weight tube " so as not to introduce any chance of dissimilar metal corrosion issues . I know epoxy should maybe encase the insert tube but not looking to take a chance

Last edited by Stewbronco : 10-19-2019 at 11:32 PM.
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  #18  
Old 10-19-2019, 11:06 AM
rvbuilder2002 rvbuilder2002 is offline
 
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If built per plan the counter weight is a galvanized water pipe.
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  #19  
Old 10-19-2019, 04:15 PM
Stewbronco Stewbronco is offline
 
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Default Water pipe

Great thanks .... someone had mentioned that it was galvanized water pipe but I actually thought it was a " tongue in cheek " comment. That makes things super easy then. Just need some longer rivets and I am fully supplied I think to start .... Many thanks for all the help and excellent suggestions. Cheers. Stew
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