Rib stitching vertical stabilizer

[otrcman]

The mention of Ray Stits reminded me of another consideration in regard to "how it was done at the factory".

The factory airplanes were covered in cotton and dope. With a dope job the tautness of the final finish is due primarily to the dope. With (at least Stits) a synthetic fabric/finish, the tautness is due primarily to the dacron fabric. A dope job is much stiffer and less prone to drumming than is a Poly Fiber job. I don't know about any of the other finishes.

So the large, open area at the base of a Taylorcraft fin may be worth a second look if you are contemplating the use of a modern cover system, factory configuration
notwithstanding.

Dick

[PA1195]

To which Ray Stits in the video would snap his finger on the covered and single stitched landing gear - thump!

Gary

[Mark Bowden]

Kinda like putting a stitch in the middle of the gear leg as another example of a stitch not tight to structure.

[N96337]

The other thing worth mentioning here is that rib stitching doesn't necessarily have to be pulled down tight to the rib. It can be used with just enough tension so as to prevent drumming in instances such as this. I learned that from none other than Ray Stitts.
John

[3Dreaming]

I found this picture of the A model assembly interesting. Notice the fully covered vertical fin being installed. default (29).jpg

[Ragwing nut]

They did that for the 41 deluxe, but I have not seen it on other models.

Could have been a prewar thing only. Need to look at a postwar vertical.

[3Dreaming]

The bottom one wasn't stitched. They had a 3/8" metal strap that pk screwed at the front and wrapped around the vertical post with pk in it. Then it was taped over.

They did that for the 41 deluxe, but I have not seen it on other models.

[Hank Jarrett]

Are there any photos or drawings of that? I have never seen it before, but it could explain some old photos!

Hank

[Ragwing nut]

The bottom one wasn't stitched. They had a 3/8" metal strap that pk screwed at the front and wrapped around the vertical post with pk in it. Then it was taped over.

[Bruce Caldwell]

Good call Mark, Thanks! I think I will just stitch the top rib. I really don't think the lower rib needs it and don't want the puckering that it would cause.

[Mark Bowden]

There may be an in-between solution as well.
These photos are from 1963 in Irish Linen

It appears from the slides that the aft half of the lower vertical rib may have been stitched. There is stitch tape evident. However from the smooth curve of the paint stripe going up the vertical it appears to be way to smooth to have the front 1/2 half of the rib stitched as there are no puckers. Zoom in and you can see it.

Of course the answer with respect to the actual "need to" stitch could be quite different between the use of linen vs. polyester.

I would suggest that given Taylorcrafts efforts at removing rib stitching in the wings of the '46's that they looked at all areas to remove stitching like they removed the rib in the vertical. Less stitching = less cost in pre vs. post war. And better appearance.

Tray-3A-1963-64-77a.jpgTray-3A-1963-64-78a.jpg

[Mark Bowden]

IMG_20190430_134701961_HDR (2).jpg This is what a two rib vertical will look like with the lower rib stitched. It was done in 1999 whether factory correct or not on Ceconite. It is a July built 1945 with the two vertical ribs in alignment with the two hinge rudder ribs. As Rob indicates and seeing Scott's at Oshkosh stitching the top only looks better.

[Bruce Caldwell]

Looks like I'll just stitch the top horizontal rib at 2.5" I cant thank you guys enough. Don't know what I'd do with the forum.

[Scott]

Two ribs, stitch the top rib only was the conclusion I reached after researching. It also becomes clear when you see how far the fuselage top tubes pull the fabric away from the lower rib.

once you've shrunk the fabric, push it to the rib with your fingertips in the stitch locations. You'll see it takes alot of pressure, and the fabric takes an unsatisfying line.
There is a third option, which is to stitch to the rib (as opposed to stitching through the fabric on the other side) but don't pull the lacing tight. I'm not sure there much purpose to this and can end up looking odd.

When mine was covered in the sixties, only the top rib was stitched. This works, and the fin ends up with a nice natural shape.

I used 2.5 inch spacing only because I did all stitching at 2.5"

[Robert Lees]

Vertical rib spacing is different, Tom, as are the overall dimensions between the pre-and post-war fins.

I'll bow out of this discussion now; good luck Bruce coming to your own conclusion.