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Old Apr 22, 2012, 03:56 PM
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United States, MD, New Market
Joined Apr 2010
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Question
Pull-Pull Rudder/Tail Wheel Question

Got back into building after many years of ARFs due to job related work load. When I did build I never had an airplane that had a pull-pull rudder so this issue is new to me and I'm wondering if those of you that have been at this longer see any problem with what I've done. Just finished up a Sig 1/5 scale Cub. On the first flight (which was GREAT by the way, except for the whole "landing" part!) I had my brand new Saito 72 set to idle way too slow and I ended up going dead stick. Set the Cub down just about 10 to 15 feet short of our runway. The actual landing was pretty good, even minus power, but the Cub didn't roll very well in last season's left over, dried out corn crop remains (are all fields surrounded by corn fields, or just all the ones I've flown at?). The Cub flipped over once, tail over cowl and landed on it's wings. Once home, I noticed that the little springs that Sig supplies to connect the tail wheel movement to the rudder movement were missing. Went to Ace Hardware, Lowe's and Home Depot to find replacements, no luck. Went back to the field. Less luck. Anyway, what I ended up doing is making two small wire push rods out of the smallest gauge piano wire I had available (picture attached). My concern is this. Is the "give" provided by the springs really necessary in this application, or will the wires work out just fine. I've moved the rudder to max deflection left and right and can hear no servo binding. Am I missing something?
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Old Apr 22, 2012, 06:33 PM
KE your cub.
Curare's Avatar
in the gutter, again....
Joined Jun 2005
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I've done similar things. If you're flying from grass or something soft, you'll probably not have any problems as the ground will provide some 'give'

If you're flying from tarmac, you may want to consider adding springs, but even then I doubt you'd really have to.
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Old Apr 22, 2012, 06:58 PM
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United States, VA, Fairfax
Joined Jan 2006
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Hi Homer, you might want to pick up "servo saver"connectors -- Dubro (I think it is but please dont hold me to the manufacturer) to reconnect your tail wheel. The springs are part of the package, I quite like them and they do save on servo damage.

FWIW, Our landing strips here in Virginia are surrounded by trees - usually Oaks.

soft landings!
cw
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Old Apr 22, 2012, 09:01 PM
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United States, MD, Elkton
Joined Oct 2011
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The springs are nice for scale,but aren't necessary..I have actually removed one of the two wires and just put a heavier one on one side.
make a small z-bend in the middle,for some "give" and easy alignment adjustment.works for me.
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Old Apr 23, 2012, 09:40 AM
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Quote:
Originally Posted by Carl'sbones View Post
Hi Homer, you might want to pick up "servo saver"connectors -- Dubro (I think it is but please dont hold me to the manufacturer) to reconnect your tail wheel.
Du-Bro #120
Great Planes #GPMQ3890 - scroll to the centre of the page.
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Old Apr 26, 2012, 08:35 AM
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United States, PA, Beaver
Joined Sep 2001
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Solid wire SHOULD be fine. I've also used fishing line as a pull\pull sort of affair.
My buddy made up some springs like the full scale ones. They work REALLY well.

This was the only pic I could find. Kinda small but it should get the point across a lot easier than trying to explain.
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Old Apr 26, 2012, 03:11 PM
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United States, WA, Prosser
Joined Jul 2011
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I ended up making a Z bend for each end to connect to the control horns but then cut it about 3/8" from the z bend and then soldered a small nut on the end of each. I then cut a piece of fuel line for each side and slipped it over the nut. The fuel line has enough give to help with bumps and jarring but I still have positive control which I could never get with the springs.
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