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My wife and I have just purchased a 750 STOL kit that was approximately 50% built. We are first time builders and are very excited to be taking over this project. In looking over the work performed by the previous builder I am noticing that ALL the control cable stop sleeves were swaged in 2 places VS 3 places.
Is this serious enough that I should remove all of the finished control cables and start over? The cable is 1/8”.
I believe standard practice is to swage in three places. Any feedback would be greatly appreciated!
Unfortunately these swages need to be redone. Two swages are acceptable on 1/16" and 3/32" thick cables...on 1/8" cables, three swages are required. The pic shows the sequence. Invest in a quality swaging tool. Also, Jon Croke has a great method of using cleco pliers that really makes the process easy: Plane and Simple (kitplanes.com)
Thank you Don. Is there any good way to cut the sleeves off without damaging the cables?
It's possible, but by no means guaranteed to work. The swages themselves are relatively soft. If you put a really thin wheel on a Dremel or similar grinding tool you can cut a notch longitudinally along the swage (basically the horizontal lines in your picture) and use two vise grip pliers along the sides of the swage to pry it apart along that line. Given the softness of the material, you should be able to split it apart without cutting all the way through, so only go as deep as necessary. Don't cut deep enough to hit the cable though, or you'll have to replace it. If using a thin enough wheel, it is technically possible to cut all the way though without actually hitting the cable, but that would have to be some seriously detailed cutting. Cutting most of the way and using brute force to pry it apart is safer.
everyone is free to do as they please when building their aircraft but I tend to err on the side of caution. I personally would replace the cables. My reasoning is that when a cable is swaged the sleeves and cable become one strong unit with the swage and cable forming to each other and the cable being tensioned around the thimble. When this assembly is comprimised such as the cable being slightly deformed to the originall swage and then dis assembled it will be slightly weakened. I could be mistaken but for 1.35 a foot (spruces price) I would have better piece of mind and more confidence in the plane. If cost is an issue then replace the longer cables and use those cables to replace the shorter cables where the original swaged connections could be cut away. Just my 2 cents.
Might be a dumb question but couldn't you add the third swage to the existing sleeve, right in the middle?
probably not a good idea, see the sequence for swaging is the center swage first. As you do each swage the connector expands outwards, so doing the sequence in correct order is important.
Thanks Arnie. Good answer. I'm looking at swaging tools now.
I would recommend you look at AC 43.13-1B Acceptable Methods, Techniques, and Practices - Aircraft Inspection and Repair.
This is the FAA's guidance to repairs upon aircraft. It can also be used to learn how to properly do many things while building your own aircraft.
It can be downloaded here:
I would direct you to pages 7-32 through 7-34 where it talks about the Nicopress Process.
What you will also need (if you don't have one) is a GO-NO GO SLEEVE GAUGE.
Aircraft Spruce sells them here:
Hope this helps,
Thank you for your replies. I am so thankful to have this community as a resource, especially as a first time builder. :)
I did consider putting a swage in the middle of the sleeve, but I was concerned with it loosening the swages on either side. I have new sleeves, a swage tool and a gauge on order from AS.
One of my main questioned that I am trying to get answered what is the construction material used for the sleeves that Zenith supplied in this kit from back in 2009? The relevance of this question is stainless sleeves only require two compressions according to the sleeve manufactures paperwork. See attached image of sheet that I found in the kit. 9408F54B-52CD-4E26-A423-8B8A7792B139.JPG
I am hoping to get this question answered from the sleeve manufacturer. I am going to examine it more closely today to attempt to determine if it is zinc coated copper, aluminum or stainless.
Finally, Earnest, thanks for the suggestion on AC 43.13-1B! I have printed the relevant pages for review.
Attached should be Zenith's Construction Standards.
Also can be found at:
On page CS #500 you will see "Detail T" in it Zenith calls out the sleeves.