In search of original wing wire clips (update Jan 2026 see page 7 and later)

[kevinbrooker]

For shipping I was thinking a coil in a padded envelope with plywood panels to keep it from crushing. USPS is $11 for the Flat Rate.

Yes, I gave them the drawing and a section of wire and a rib. the rib was the "Ah ha..." moment putting the end use in context. The tooling engineer realized there needs to be some tension between the holes to keep the fabric from ballooning up.

Stamped parts need to be in some quantity or the tooling costs cannot be amortized. I was thinking Shinn brake adjusters since those systems were used on other aircraft too. Might just be the ramps and the owner can braze on the threaded rods for a more owner made thing. These guys might also be able to stamp it with the threaded "rod" as one piece and add the threads.

The tooling is not just the slides which bend everything. The slides are driven by discs which have a track path built into the surface. A bearing connected to a drive rod (my terms not the actual name) follows the track and transfers the movements into the slides. The discs are all attached to shafts which are synched up to choreograph the bending of the finished product. Each disc is bespoke for the job it must do. There are some discs which can be reused on other products but some need to be made for a specific part being bent up.

[kevinbrooker]

I heard back from the machine shop and they can make up the wire. The costs are in the tooling. The wire is under $1/lb. The run time is also pretty inexpensive. The tooling is near $8,000 (eight thousand US dollars). To offset and amortize the tooling costs the more wire (in feet) that is made the less expensive the wire becomes. The first foot costs almost $8100. Run a second foot and the per foot costs drop to $4050. Really rough math has 1000' costing $8.25 per foot. 4000 feet the costs drop to about $2.50/ft and at 10,000' the costs is about $1 per foot.

Changing up the spacing for another airplane type costs almost nothing but defrays the tooling costs assuming the bend remains the same.

[kevinbrooker]

Too excited and hit post too fast.

The title should be wing fabric hold down wire clips. Sorry for any confusion.

[3Dreaming]

I would take a 1000 feet if we can get enough interest to get the price down to $1.00 per foot. With that you are a tenth of the way there.

[Robert Lees]

Link to kevinbrooker update:

https://vb.taylorcraft.org/forum/taylorcraft/buy-sell-aircraft-parts-services-shops/197636-it-can-be-done-costs-for-having-wing-wire-made

In essence: it can be done...we just need an order of scale to keep the cost per unit down.

[Robert Lees]

Kevin: I've merged your latest post with the most relevant thread. If you see missing posts, or if you see I've missed anything, please let me know. It's important to keep this thread at the fore.
Rob

[kevinbrooker]

Great. I started a new thread to not bury the headline and agree its important to have continuity. Thanks for making the change.

[Jim Herpst]

Posted earlier but a reminder I will take 250 feet

[Mark Bowden]

In an effort to get to 10K ft, I will take 1000' (~4 aircraft). Maybe even 1,250. With the condition that the assembled group order is over 3-4000'. Same question for Jim and the Bakers and all of us, what is your max price point?

Kevin, a question is how long they would store and maintain the tooling, both hard and soft (machine programs, etc.)
And then if we get an intial order placed, what is the set up charge and minimum feet order for another batch?
Also, what wire alloy are they proposing? The Aeronca drawing specifies Spring Music Wire, AN-W-17. A Martin tag has Stainless Steel, 302H.

Again, Kevin great work. And nice sea plane article in GA News.

[Jim Herpst]

I am assuming we will get to 10000 feet as far as a price. Frankly we should get to 10000 in a reasonable amount of time

[Mark Bowden]

Legally, these will have to be owner-produced parts to be installed on our aircraft. That means specifying the alloy. The two reference materials are an option; modern music wire is available but has very different chemistry and mechanical properties compared to 302 stainless. The upside of this large difference is you are likely safe to use a variety of options. The key responsibility if they don’t want to use either is that we have to review the properties for use in the intended part.

302H (H = full hard) is available generally listed as 302/304 (304 has less carbon). We’ll have to look at tempers against the PMA’d Martin wire 302H reference standard. This also includes the formability of the wire and it’s spring back properties and if they can form it.

Another factor is wire coating for dissimilar metals protection, stainless and aluminum don’t mix well. And the wire essentially acts as a mechanical saw cut in the rib hole over time. We need to see what they offer in terms of coatings. Wire often has Nickle or soap coatings, neither are good for Aluminum or fabric adhesive systems. Soaps are used as die draw and wire forming lubricants. Soaps will cause delamination of the fabric adhesive and primer systems. Epoxy primer is likely best. We can see if they can affordably coat the wire or you could do it yourself when you recover a wing.

If bare stainless eaiset and cheapest for them, then prior to installation I woudl clean the wire with MEK or (new MEK) to remove the lube/soap and prime the wire.

Kevin, I would be happy to help in your conversations with them if you wish.

[kevinbrooker]

The wire will come cleaned of all lubricants from the fab shop. They based the tooling on making he wire out of 302 SS and one of the bending slides uses a roller since the stainless can gall a bit while being bent.

[Jim Herpst]

Kevin just gets better and better. Great job! Seems like we have a pretty good number ready to reach 10000 feet between here and Facebook. Those that simply stated sign me up or I will take a set I assume mean 250 feet which would be a minimum for each. We need to clarify such it would seem.

[tagflyer]

I am speaking up for a fellow pilot who is not on FB or this site as far as I know. He’ll take 300’ and if price is $1.00 or less, he’ll take another 200’.

[Mark Bowden]

Great news on 302 stainless, but what temper?

Our reference data is Aeronca music wire and Martin wire, which is 302H. Properties change with temper, especially formability and springback allowances (how much you have to over form/bend to get the desired formed angle).
Thanks.