Lacing the vert fin ?
- Thread starter jon
- Start date
Longwinglover
Registered User
Charlotte, NC
Top rib only, two stitches equally spaced is how Mr. Piper did it.
John Scott
John Scott
Steve Pierce
BENEFACTOR
Graham, TX
J-3 thru PA18-95 were laced as John posted. PA18-105 thru 150 have 4 stitches on the top rib. 4" from the rudder post, spaced 4" apart.
bob turner
Registered User
I keep my Cub original, sort-of. The first time I did it, the standard pair of stitches pulled out almost immediately. Second time I doubled up on everything - fabric, reinforcements, and stitches. Still pulled out. Last time it was drilled aluminum washers about 1" in diameter with rounded edges over a double fabric layer, stitched with .032 stainless. Still pulled out, and the washers and stainless stitches are still in there.
Doesn't seem to affect flying characteristics at all. I guess it is the giant slips that pulls them out.
Doesn't seem to affect flying characteristics at all. I guess it is the giant slips that pulls them out.
Clyde Barker
Registered User
T74
When I built my experimental Cub I didn't know any better, so I laced both ribs. I used 2" spacing, and so far (400 hours) it has held up well. I only have 100 hp though...
http://sparky.supercub.org/photopost/showphoto.php?photo=235&size=big&ppuser=1999
Clyde
http://sparky.supercub.org/photopost/showphoto.php?photo=235&size=big&ppuser=1999
Clyde
Steve Pierce
BENEFACTOR
Graham, TX
I am told it will ballon out but have never seen it happen. Have a PA16 in the shop now with a recent recover and no stitches. We are planning on stitching it. Never had them pull through.
Bob, any ideas why?
Bob, any ideas why?
SuperCub MD
Registered User
Collins, Wisconsin
I've never been able to tell any difference in flying them when the fins are stitched or not. I'd go with about 8 or more stitches on the upper rib, more won't hurt anything, and I've seen 4 break. If nothing else, the stitching will keep the fabric from drumming a little, and hopefully the finish from cracking at the edges of the fin.
I've switched to Superflite's flat cord, much stronger than stits. Stop over at the hanger and I'll give you a couple yards to use on your fin if you want to try it.
I've switched to Superflite's flat cord, much stronger than stits. Stop over at the hanger and I'll give you a couple yards to use on your fin if you want to try it.
bob turner
Registered User
Mine always pull out, but I only use two. I do one giant slip every time I fly, which is about 180 days a year. The safety wire/aluminum washer arrangement pulled out after about five years, with a C-65. Been flying with no stitches since then, and no cracks. That is about 19 years of stitch-free flying.
Mr. Dart, do C.C. use heavy duty fabric on the fuselage? Jim & Dondi
Miller at Aircraft Tech. Support recommended it, but not required.
Just wondering if that is why C.C. do not lace. With the H.D. fabric
it appears to be very stout without lacing, and looks better.
Do most cubs use the H.D. fabric ?
Jon
Miller at Aircraft Tech. Support recommended it, but not required.
Just wondering if that is why C.C. do not lace. With the H.D. fabric
it appears to be very stout without lacing, and looks better.
Do most cubs use the H.D. fabric ?
Jon
Dano Bardwell
Registered User
big lake Alaska
laceing
I lace the vertical on the top rib only like mr. Piper but I sew it like I would wing ribs in the prop wash area. every 2.5" looks great & i havent ever blown out stitches even with the 180hp .
I lace the vertical on the top rib only like mr. Piper but I sew it like I would wing ribs in the prop wash area. every 2.5" looks great & i havent ever blown out stitches even with the 180hp .
