Martin wire

[Nefj40]

Just say no.

[flylo]

Re: Martin wire

Never worked, never will. Close but no cigar

[Hank Jarrett]

Re: Martin wire

Seriously?!?!?! NOT even close, not even a rubber cigar! We have GOT to find the old Taylorcraft wire machine (and failing that I have a couple of companies I will be contacting to see how much they want to make a run of the RIGHT Taylorcraft wire. Lord only knows what those screws did to the wire hook holes!

Hank

[flylo]

Re: Martin wire

Since I broke by back I get alot of recliner flying time & should make a wire form & bend some up.

[Nefj40]

Re: Martin wire

The screws actually where in-between the wire holes, bonus holes in the rib. It was to hold down the wire that naturally wanted to bow up.

[Scott]

Re: Martin wire

I guess they did the job but it's a shameful mess really

[Bruce Caldwell]

Re: Martin wire

Are these the Martin clips that are sold by Aircraft Spruce? I bought a roll and they look like they are pretty close. Help!

[Hank Jarrett]

Re: Martin wire

Martin wire IS close, but not close enough. It is too long between the clips and looks terrible no matter how you take the slack up. Having extra length that is pulled down also puts compression on the wire that can cause the wire to pop out.

Hank

[Nefj40]

Re: Martin wire

Thankfully they had the correct wire for most of the left wing, it was only the first few ribs out from the fuselage, top and bottom. Sadly, looking at the right wing I'm afraid the entire wing got the martin treatment. Another thing that I noticed about the two different wires is that the martin has a bigger barb, meaning that the Tcraft wire was easy to remove while I had to struggle with the martin.

[Scott]

Re: Martin wire

I suspect the holes in the rib flanges are torn, to a keyhole shape

I wasn't looking forward to lacing my wings, but I am happy with the result. The task itself, notwithstanding the sore fingers, in the end was not that bad. Once we got the hang of it, a pair of ribs took us ( my daughter helped me) about 40 minutes. Perhaps not that much longer than tweaking wire and in this case drilling holes and installing PM screws top and bottom.

Unless really hung up on authenticity, lacing is a good (from an airworthiness perspective better imo) option.

[skip]

Re: Martin wire

I suspect the holes in the rib flanges are torn, to a keyhole shape

I wasn't looking forward to lacing my wings, but I am happy with the result. The task itself, notwithstanding the sore fingers, in the end was not that bad. Once we got the hang of it, a pair of ribs took us ( my daughter helped me) about 40 minutes. Perhaps not that much longer than tweaking wire and in this case drilling holes and installing PM screws top and bottom.

Unless really hung up on authenticity, lacing is a good (from an airworthiness perspective better imo) option.

I did my wings a few years ago and was fortunate to get some NOS Taylorcraft wire. I suspect that the wire with the hold-down screws shown at the top of the thread was Aircraft Spruce wire. I did some comparisons and posted some pictures to the forum a few years ago that shows the bow-up in the Aircraft Spruce wire.
Bottom line, If I had NOS Taylorcraft wire I would use it again. I really like it and think that it does a good job. But with the new manufacture slightly-off wire available today, stitching is probably the best bet.

We really need to figure out how to rig a machine to crank out properly dimensioned Taylorcraft wire.

[flylo]

Re: Martin wire

If you have 2 people, one on each side & use several needles stitching goes pretty fast & isn't too bad.

[Hank Jarrett]

Re: Martin wire

Problem with stitching is it is NOT approved for stamped rib wings. Even though I tend to roll my eyes at many things the Feds say is "not approved" this one is a good one. The stamped ribs do NOT have the edge of the rib rolled under far enough to clear the stitching cord. The cords will rub on the sharp edge and can be cut by the edge of the ribs. If you are going to rib stitch a stamped rib you need to either roll the edge in far enough ON EVERY RIB that the cord does NOT touch the sharp edge or you need to put something over the edge to protect the cord. Doing this "SHOULD" require some kind of official approval since it modifies the rib and or the covering procedure specified in the Type Certificate. If it isn't shown in the log book you are probably NOT LEGAL and probably NOT SAFE!!!!! That was the safety of flight part of the rant.

The LEGAL part of the rant is that Taylorcraft NEVER approved of rib stitching on stamped ribs. The letter floating around from Dorthy Ferris is for a PRE WAR ribbed wing with stick ribs. Those planes WERE rib stitched. You can use stitches on ANY stick rib wing, even if it is on a post war plane. You CAN NOT use stitching on a POST WAR WING even if it is on a PRE WAR plane! If you stitch a stamped rib wing you are putting your life and your mechanics certificate at risk. If you HAVE a stitched wing wing stamped rib you really should open up the inspection covers and take a CAREFUL look inside for dangling stitching cords. They DO get cut! Remember that Taylorcraft DID allow the substitution of one type rib for another on ANY WING so many aircraft have a mix of ribs. You CAN NOT use wires on stick ribs and you SHOULD NOT use stitching on a stamped rib. There are lots of planes with a mix of ribs, and YES, that means there SHOULD BE wings with some ribs stitched and some with wires.

Hank

I am NOT addressing all of the wings that have STCs or other approvals for screws or rivets. That is a whole different "Kettle of Fish".

[Scott]

Re: Martin wire

Not sure where you've found a broad prohibition on stitching stamped ribs, there's lots of them out there including from manufacturers. applying anti chafe tape on potential rub points is just a basic practice requiring no specific approval.

While TAC may not have used stitching on wings, they most certainly did on all flight controls stabiliser, and the fin, all of which have stamped ribs. There is one reason and one reason only for using wire.... lower labour cost. Time saving is a legitimate reason, but has nothing to do with airworthiness or even best practice.

I'm fully confident my maintenance licence is well served by using acceptable methods and standards over production motivated shortcuts implemented by a financially failing manufacturer.

[Garry Crookham]

Re: Martin wire

I agree with Scott, so does the FAA's Denver ACO. See the 337 in the Tech Resources section of the Taylorcraft Foundation.