Pietenpol-List: hard wire rigging
Posted: Fri Oct 08, 2004 7:42 am
Original Posted By: Michael D Cuy
Regarding the use of "hard wire" for rigging, as per the old Piet plans, there has been much back-and-forth discussion of that over the years. Most of it is along the lines of "we have much better, modern stuff these days" and will tell you not to do it. However, looking through the great majority of details in the old Flying & Glider Manuals will show that they use wire with twisted "ferrules" almost exclusively.In the archives on the BPA site somewhere (the Grant McLaren site), is an article on making a tool to form the wire ferrules. It also shows how to properly install them. Again, you'll probably hear considerable nay-saying about this and maybe also about how a ferrule with a round inner shape does not properly secure the profile of two wires side-by-side and that the ferrule needs to be flattened for proper installation. I don't know about all that but I had planned to make one of those ferrule-and-loop tools and get a spool of wire from McMaster, make up a representative samples using wire ferrules vs. conventional thimble and aircraft cable, and test them both to failure. Many of the nay-sayers express concern about hardening, embrittlement, and/or fatigue of the wire where it forms the ferrule and eye, and that would no doubt be the point of failure. I just don't believe they would fail at any loading lower than would occur at the point of connection of the tab that connects the wires to the wood framing of the stabilizers, or of some of the other construction points.For the really authentic old-time look, the wire bracing is really interesting to me and I believe it can be done safely and adequately using the right tools and methods. That, however, is my own personal opinion and is completely NOT flight tested!Oscar ZunigaSan Antonio, TX________________________________________________________________________________Date: Fri, 08 Oct 2004 09:07:06 -0400
Regarding the use of "hard wire" for rigging, as per the old Piet plans, there has been much back-and-forth discussion of that over the years. Most of it is along the lines of "we have much better, modern stuff these days" and will tell you not to do it. However, looking through the great majority of details in the old Flying & Glider Manuals will show that they use wire with twisted "ferrules" almost exclusively.In the archives on the BPA site somewhere (the Grant McLaren site), is an article on making a tool to form the wire ferrules. It also shows how to properly install them. Again, you'll probably hear considerable nay-saying about this and maybe also about how a ferrule with a round inner shape does not properly secure the profile of two wires side-by-side and that the ferrule needs to be flattened for proper installation. I don't know about all that but I had planned to make one of those ferrule-and-loop tools and get a spool of wire from McMaster, make up a representative samples using wire ferrules vs. conventional thimble and aircraft cable, and test them both to failure. Many of the nay-sayers express concern about hardening, embrittlement, and/or fatigue of the wire where it forms the ferrule and eye, and that would no doubt be the point of failure. I just don't believe they would fail at any loading lower than would occur at the point of connection of the tab that connects the wires to the wood framing of the stabilizers, or of some of the other construction points.For the really authentic old-time look, the wire bracing is really interesting to me and I believe it can be done safely and adequately using the right tools and methods. That, however, is my own personal opinion and is completely NOT flight tested!Oscar ZunigaSan Antonio, TX________________________________________________________________________________Date: Fri, 08 Oct 2004 09:07:06 -0400