Wing strut adjustment bolt

[BSchoonmaker 3]

I have nearly finished adding the fairings and preparing my left wing strut for paint. Only the left strut has the ability to change the wing incidence.  Is it worthwhile to add that capability to the right strut or is it not worth the effort/cost?

[High Country 69]

No need to add a new one just keep moving along with what you have going along and get that bird in the air!!! good luck

 

 

 

[edit] there is no real need for a second one and this is the weakest point of the entire lift strut so why add a new weak point.

Edited 4 Aug 2014 by High Country

[BSchoonmaker 3]

Good point about it being the weak point of the support system.  No doubt true.

 

I did wonder if the second adjustment point might give me the opportunity to adjust out most of the twist from both wings and therefore maybe gain a little speed.  With the single adjustment I can only duplicate what the right wing looks like.

[EDMO 1078]

Read the strut testing in "files and forms" and you will see that the bolt did not fail until 15G load was added.

It may be the weakest part,  but too many G's for the pilot!

EdMO

Edited 4 Aug 2014 by Ed In Missouri

[High Country 69]

Ed- you're right they are not an area of concern i was just pointing out that they are the weakest link. I guess if a guy wanted to put one in you could use an even bigger one than the originals too if it makes you feel better.

 

These are more for making fine adjustments not really for adjusting the actual full twist of the wing. what wing do you have and what is the twist anyways?  If you had one in each wing you could split the difference in the adjustments rather than just matching the fixed one with the adjustable one but they should be built close enough anyways that it should not take that much to match up. just my .02 cents either way I say do what suits you best thats the beauty of experimental.

Edited 4 Aug 2014 by High Country

[C5Engineer 1170]

Kitfoxes have them on all 4 attach points.

[akflyer 1427]

I have thought about adding another one to my right side so I can take some of the twist out.  Seems like a quick way of trying to get some of the twist out versus rebuilding the entire wing.

 

On RC models, I have just used my hands to twist a wing then a heat gun to shrink the covering to hold the shape I want to get the washout right.  I don't see why I couldn't do the same with the avid.  I have just grabbed the wing tip and twisted and it showed wrinkles in the covering that I am sure I could get out with a heat gun just like I do on RC models. 

 

[1avidflyer 1983]

I would be very careful about using a heat gun on the fabric.  If you get it much over 350 degrees, it ruins the fabric.  Just looked in the poly fiber manual, and it says that "at about 375 the filaments start to thermo-soften and loose all measurable tension.   At 415 degrees they start to disintegrate."  Hard to know for sure what the heat is coming from the heat gun temperature wise.  I know that the poly fiber finishes melt from heat also.  Jim Chuk

[akflyer 1427]

True.. Dont use the heat gun that you would use to remove stickers that gets to 1500 degrees or some crap like that.  I use a model heat gun and a temp gun.  It is very easy to watch real time with the temp gun just how hot your getting the fabric surface.  I have never had to go over 275 to get any wrinkles out.

 

[EDMO 1078]

I wonder if he has tried setting his flaperons to about a negative 3 degrees - some have done that for better cruise.

Leni,

     I found a bargain on aviation rod ends on ebay - They were new 7/16-20 thread with 5/16 holes - I bought Four of them - I know the magnum still uses 1/4 inch bolts, but there is room to use 5/16 and I reamed my strut fittings for them.

     somewhere on here I said I just spent $400 for nose gear parts - Forgot that the price includes the threaded inserts for my new 1" struts and the new  strut/fuselage attach fittings that you gave me the 26 degree angle for.  Thanks for the info.

EdMO

Edited 5 Aug 2014 by Ed In Missouri

[thebriman 69]

Plenty of Kitfoxes still have the wings attached.  I would add it.

[EDMO 1078]

7/16 was the old thread used on the J3s - Then Piper got paranoid and went to 5/8 thread....

Piper has threaded fittings on both ends of the struts.

EDMO

Edited 5 Aug 2014 by Ed In Missouri

[BSchoonmaker 3]

My aircraft is a C model with heavy hauler wings.  I did not build the wings so I do not know the amount of washout - another reason to add the extra adjustment capability.  Looks like that is what I am going to do but stick with the standard 1/4 bolt if it held to 15g.  I think that is well beyond the point at which other parts might fail and well above the loads to which I plan to subject it.

 

I do plan to rig my flaperons so I can fly with them in a reflexed position to see the result.  Since I am making MANY drag-related changes to the airplane I plan to report, in detail, on my performance so others can evaluate the impact of serious drag reduction to the airplane.

 

Thanks for all your comments.

[akflyer 1427]

By reflexing the flaperons ( I hate that cause then the plane gets heavy on the stick not the light nimble feeling that I love about the plane) your putting lipstick on a pig.  The amount of washout in the wing built stock (1.5-1.75" on a stock C HH per the book) is redonkulous!

 

Reflexing the flaperons may help the plane not take a nose dive if you let go of the stick, but it makes the plane fly like crap.  I like mine much better with 10 pounds of lead strapped to the tail spring versus trying to trim with flaperons.  By getting the CG right, the plane will take off and land shorter and have a much sportier feel in the air and be lighter on the controls.  I guess I need to get off my ass and order some more rod ends to do the right wing like I have been threatening to do for the last few years