Wings and spars

[Dalton]

Re: Wings and spars

Hey Guys,thanks for all the great advice and sources,what a great forum here! We have decided to replace the spars in our T,seems like with 60 plus years and over 50 on floats with original spars, might be time. Are any drawings available for the wing assembly?I've done a couple of champs and a cub and found these dwgs. to be a great help.

[citabrickr]

Re: Wings and spars

Check your FAA STC listings guys, there is an STC for installing PK screws (similar to Fleet/Aeronca) in the stamped ribs. Did one once, many years ago.
Mikeg

I got a field approval to stitch F21 wings, stamped ribs, just taped the edges of the ribs, no problem at all and much better retention and appearance.

[lawheelock]

Re: Wings and spars

Check your FAA STC listings guys, there is an STC for installing PK screws (similar to Fleet/Aeronca) in the stamped ribs. Did one once, many years ago.
Mikeg

Don't forget the Stinson 108 series. They came from the factory with PKScrews.

Larry Wheelock TF671, Stinson 108 N584LW, BC12D N96179

[mikeg]

Re: Wings and spars

Check your FAA STC listings guys, there is an STC for installing PK screws (similar to Fleet/Aeronca) in the stamped ribs. Did one once, many years ago.
Mikeg

[M Towsley]

Re: Wings and spars

Dalton,

If it comes down to it, there is a lot of info on here about modifying the common 'Martin Wire' that is no longer available commercially. It involves placing a 'Z' bend in it to shorten it between the holes. Use the search function and you can find it. Welcome and good luck!!!

[Robert Lees]

Re: Wings and spars

Well the clips (more accurately called Taylorcraft Wire) for the stamped ribs are difficult to find.

I don't think there is any preference between stamped or truss ribs (I have owned aircraft of each type).

But having re-fabricked both types, I sure prefer the Taylorcraft Wire ("clips") over stitching!

Some photos of using the Taylorcraft Wire on my webpage here; note I use the word "clip" to mean Taylorcraft Wire.

This photo might be of interest to you, it is the difference between Taylorcraft Wire and "Martin Wire" sold by certain aviation houses. Note the difference in the shape of the barb and the spacing between the barbs.

Rob

[Dalton]

Re: Wings and spars

Hi Robert, and thanx for the welcome, as for history supporting your reason,you may be right after all as we had many stitches cut through when we stated disassembly.Do you know if the clips can be found for the stamped ribs,and is one rib preferred over the other?

[Dalton]

Re: Wings and spars

Hi Ryan,I'll check wag for spars,do you still have the truss ribs and would you be willing to sell them if we can't find any?By the way I have looked at your restoration photos and what a great looking airplane you have!......Regards

[Ryan]

Re: Wings and spars

Got my spar stock from aircraft spruce. Wag aero is now selling ready made spars. My wings were mixed as well. Left was stamped and right truss. I went all stamped to have a uniformed look instead of one using clips and the stitching.

[Robert Lees]

Re: Wings and spars

Hi Mike, and a belated welcome to the Forum!

Others will supply details as to whether the wings can be mixed & matched, and for spar stock , but first count the number of ribs on each wing ... they should be the same (either 13 or 15).

Also check for rot in both wood & metal caused by mouse teeth & urine respectively !!!

Personally I don't like stitching on stamped ribs, because the sharp edge of the stamped ribs could potentially cut the cord, but history (like yours) does not support my reasoning. It may be illegal (in terms of there is no "approved data" for stitching on stamped ribs) , but I may be wrong.

Rob

[Dalton]

We stripped the old fabric off the wings and found three birds nests and one mouse nest.Also found left wing with stamped ribs and the right wing with truss type,can the wings be mixed like this or do we have to find another set of one or the other? Also they were both rib stitched .Haven't fully inspected the spars yet,but if needed what's the best option for spar stock?