Material Thickness Missing

[Jackal]

In the top left corner of Page 11 is shown the lug or tang to which the roll wires attach to the center section.

I could not find what thickness of 4130 is used. What is "normally" used here, or am I missing where it shows it?
All of the rest of the flying wire lugs (shown near the back of the plan set) show a .050 center blade and two .050 outer plates for a .150 thickness. The one on page 11 clearly shows in the side view that there is no "center blade" - only the two sides of the piece bent around the tube. I was thinking of using .063 if I couldn't find anymore info.

Any thoughts?

[JBMoore]

I don't remember what I used and I checked my plans.... no dimension.
The roll wire clevis is larger than the rest so if it fits in the slot, use it. The attach point on the fuselage end might be a good reference so you could use the same if you wished.
As far as the others, I don't remember making them all three thickness lugs. Again the lug needs to fit in the slot of the clevis.

Jeff Moore

[Jackal]

The other end of that roll wire attaches to one appears to be one of the most substantial pieces on the plane. I used a .090 "front piece" for that plate which doubles as the upper motor mount. I chose .090 because, although it does not show what it should be, it does show it as .090 as the "washer" on the lower engine mount. Then it clearly shows an .090 "doubler" (far left and center of page 11) on the back of that tang. Even if you used .050 for the "front plate" that is still .140 for the roll wire attach, and on mine it is .180 (barely fits inside the AN Fork terminal). I always wondered why that roll wire attach was so massive, but did it anyway. Now I really wonder considering it only needs to be as strong as the other end, and that other end, the piece in question now, does not appear to be all that substantial. Clearly it is "hollow" and does not show the center blade like the cabane attach tabs on the fuselage on the same page are shown. This is of course why I started thinking maybe that "hollow" tang is made of some pretty thick material.......... Hmmmm,

Thanks for your input Jeff.

[Jackal]

Heyyy, wait a minute. The part being discussed (the roll wire attach lug in the top left of page 11) shows a 3/8" hole. This lug attaches a 5/16 streamline wire according to the plans. Won't a 5/16 flying wire use a 5/16 bolt or pin also? Surely it will not take a 3/8" pin. None of the flying wire lugs on page 24 show a fork pin larger than 5/16. Can someone please confirm the pin/bolt diameter on the fork of the roll wires?

Also, if it uses a 5/16 hole, then the outside diameter of this attach lug would more appropriately be 1/2" or 7/16" instead of the 9/16" shown, would it not??

[hatz215]

Jackal,

I went out to measure mine but my mike broke so all I could do is eyeball with a scale. The total thickness of my upper 'tang' is in the neighborhood of .180. That pin is 3/8" also.

Steve

[Jackal]

Steve,

Thanks for taking the time to measure it. I guess I don't know much about the dimensions of streamlined flying wire fork terminals. I figured it would be the same size pin as the 5/16 fork that connects the back cabane to the middle one, which is a 5/16 bolt. Also, on page 24, all of those lugs show a 5/16 fork pin or smaller. Apparently there is a lot of load on those roll wires.

Thanks again.