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Lift struts....

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MadProfessor8138

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The Ragwing Stork that I am building calls for 4130 tubing 1" OD x .058 x 11' for the lift struts.

Since I am having such a hard time finding the plastic streamline covering material for the round tubes I thought I might just order streamline struts and be done with it.

While looking at the streamline strut material that's available from suppliers a few questions occured to me.

Do I have to stay with 4130 or can I go to aluminum ?

I didn't see a direct cross over between the round tubing and the streamline tubing in 4130 or aluminum.
Either the size was off or the material thickness was off.

Going from the original 4130 1" x .058 round tubing.......what size 4130 or aluminum streamline material would I need to replace the original ?

Kevin
 

Pops

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So you are asking what size , say aluminum streamline strut would be equivalent to the 4130, 1" x .058 round tubing. Do you know how strong the 4130 strut is designed for, 2 G's, 3 G's, 4'G's, 5 G's. You are assuming the plans 4130 strut is as strong as you would want. I would work the problem differently. I would find the load on the strut and then decided how strong I want my strut to be.

On the JMR the load on the strut is 1108.9 lbs. ( being conservative, I did not subtract the weight of the wings so its really less than that ). The Carlson strut I chose gives me a yield strength of +10.32 G's. The Carlson alum strut I used is 1.25" x 3.13"
Then you have to work out the strut attach material and bolts that you want to use.


 
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Pops

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I would use the 4130 1” and build a 6061 AL fairing to go over it. Lightest and cheapest and added stiffness
Or just hot wire some foam for the front and rear of the strut and epoxy on and then wrap with aircraft fabric and paint with a water base paint.
The prices of those plastic steamlined covering is just out of this world crazy.
 

stanislavz

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Or just male mold fron hot wire cutted foam.

Btw - how do you like plans of rw19 ? I also have them - as more i look into them - as more they look more sketchy, but less drawing.
 

MadProfessor8138

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Btw - how do you like plans of rw19 ? I also have them - as more i look into them - as more they look more sketchy, but less drawing.

stanislavz.......admittedly,the plans could be much better if they were redrawn.
With that being said.....they are still adequate to build a Stork if you are able to fill in the blanks and find modern replacements for part #'s that are now obsolete.
The videos will answer 98% of the questions a builder will have after looking at the plans.

Kevin
 

wktaylor

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You might find some useful info/knowledge in the following FAA Advisory Circular... old aircraft designs represent challenges...

AC23-27 PARTS AND MATERIALS SUBSTITUTION FOR VINTAGE AIRCRAFT
 
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