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phred737
 Post subject: Vertical fin
PostPosted: Thu Oct 25, 2012 9:58 am 
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Joined: Tue May 03, 2011 5:31 pm
Posts: 9
Location: USA
Before I start drilling holes in my vertical fin, anyone have any good techniques for keeping things straight, aligned and tight?


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phred737
 Post subject: Re: Vertical fin
PostPosted: Sat Oct 27, 2012 10:34 am 
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Joined: Tue May 03, 2011 5:31 pm
Posts: 9
Location: USA
anybody? ..... :o


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Bill Williams
 Post subject: Re: Vertical fin
PostPosted: Sat Oct 27, 2012 12:28 pm 
I'll try...In one of the back issues(92??) of the news letters there was an article by John Shinn about how he made a fixture from 2x6 to hold the fin in aligment.
I mounted my spar on the plane, drilled number 40 holes in the skin, marked the 1/4" edge distant on the ribs and measured and "eyeballed" the fin for alignment.


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Rich Brazell
 Post subject: Re: Vertical fin
PostPosted: Sat Oct 27, 2012 2:52 pm 
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Joined: Wed Oct 21, 2009 12:33 pm
Posts: 3095
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Location: Jamul, CA (San Diego area)
My fin came from Ken Knowles and the parts were "centered punched" allowing for "matched hole tooling." It came out pretty darn straight ! :P

RB


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dan
 Post subject: Re: Vertical fin
PostPosted: Sat Oct 27, 2012 9:36 pm 
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Joined: Wed Oct 21, 2009 9:30 am
Posts: 898
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Location: USA
Come on Rich, there ain't nothing on that bird that is remotely close to crooked!! It is a work of art that just happens to move very fast.......Dan


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Rich Brazell
 Post subject: Re: Vertical fin
PostPosted: Sat Oct 27, 2012 10:25 pm 
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Joined: Wed Oct 21, 2009 12:33 pm
Posts: 3095
Images: 64
Location: Jamul, CA (San Diego area)
Thanks Bro ! But there isn't an aircraft made that flys straight (probably going to get an ear full from this) ! That's why they have trim ! The older they get the more trim you need. Boom !

RB


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Bill Williams
 Post subject: Re: Vertical fin
PostPosted: Sun Oct 28, 2012 6:01 am 
I don't know if N30WW flies straight or not, but at 24/23 it will indicate 185 MPH at 1500 MSL. (ask Lee) I have one trim tab on the wing for fuel and bagage compensation. I built it as straight as I could. I do believe this is why some guys see 145 MPH cause it ain't straight.


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SHIPCHIEF
 Post subject: Re: Vertical fin
PostPosted: Sun Oct 28, 2012 11:04 pm 
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Joined: Tue Nov 29, 2011 9:05 pm
Posts: 471
Location: USA
I just attended a Sport Aire workshop at Paine Field this week end. My son Peter talked me into taking the Electric wiring class.
We got to look at Bob Archer's antennae; the ones you build into the fiberglass tips on aluminum planes.
I was wondering if the Comm antenna, which is for installation in the Vertical stabilizer tip has ever been used on a T-18 or S-18?
It's kind of tall, and would add about 9" height to the tip?

_________________
Scott Emery
EAA Chapter 326
T-18 N18TE


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Doug S
 Post subject: Re: Vertical fin
PostPosted: Mon Oct 29, 2012 8:57 am 
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Joined: Thu Oct 22, 2009 8:35 am
Posts: 129
Location: Daytona Bch, FL
I HAD the com antenna in an extended vertical tip. I removed it & put a short tip back on - the plane would get a small but annoying cyclic yaw in smooth air. First I stiffened the tip but in the end removing it solved the issue. I think the added drag of the extended fin is more than just an antenna.


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SHIPCHIEF
 Post subject: Re: Vertical fin
PostPosted: Mon Oct 29, 2012 9:24 am 
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Joined: Tue Nov 29, 2011 9:05 pm
Posts: 471
Location: USA
Thanks Doug;
That's a real "Meat & Potatoes" answer!

_________________
Scott Emery
EAA Chapter 326
T-18 N18TE


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jrevens
 Post subject: Re: Vertical fin
PostPosted: Wed Oct 31, 2012 5:29 pm 
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Joined: Thu Oct 22, 2009 10:13 pm
Posts: 789
Location: USA
Doug S wrote:
I HAD the com antenna in an extended vertical tip. I removed it & put a short tip back on - the plane would get a small but annoying cyclic yaw in smooth air. First I stiffened the tip but in the end removing it solved the issue. I think the added drag of the extended fin is more than just an antenna.


I've always suspected that would be the case... thanks for that, Doug S. Beauty is in the eyes of the beholder, but I also believe that it is an unattractive change... just my humble opinion.

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John Evens
Arvada, Colorado

T-18 N71JE (sold)
Kitfox 7 SS N27JE


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SHIPCHIEF
 Post subject: Re: Vertical fin
PostPosted: Thu Nov 01, 2012 9:53 pm 
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Joined: Tue Nov 29, 2011 9:05 pm
Posts: 471
Location: USA
I'm fairly new to T-18s so I'm not overly invested in the purity of them, however I did go to the Paul Allen's WWII fighter museum @ Paine Field. Wow! The windshield frame, engine cowl top, canopy, etc looked familiar on certain FW-190, P-51 type planes. I thought the cockpit of a T-18 to be small, and the pull back canopy a bit tight. Now I know better. How did J.T. Get it so right? Those fighters are tight and small, with similar tight canopies, yet on a T-18 the proportions look right. With the T-18 being so small, I would think the canopy would look oversized and out of place, Not So!, and the proof is in the other planes that also use the T-18 canopy.
With the T-18, the First Rule of Power Boating does apply.....Never Look Back!
All that beautiful plane from the back of the canopy forward, and almost NO plane behind!
It still amazes me.
(Hope I didn't hurt anyone's feelings)

_________________
Scott Emery
EAA Chapter 326
T-18 N18TE


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