Has anyone built a WWI A/C with a wire training edge? Does this work on a model? And how is it covered? I notice that even Glen Torrence's outstanding DrI kit has a (scalloped) wooden trailing edge.

I've seen wire trailing edges being used on WWI models built from Mick Reeves plans. Not only that, but also rudder or elevator outlines consisting of soldered wire. This might be a useful link:
http://www.rcscalebuilder.com/forum/...p?TID=543&PN=1

Here's one of that thread's images.

Looks very scale, don't ask me how it's done though

I believe the picture is of a Mick Reeves Sopwith Pup. A friend of mine is building one and the TE's are formed before being inserted onto the ribs. It's a little tricky but works well once finished. Remember thought that many WWI planes had wood TE's as well.

Man, both that Pup AND the Camel look very VERY SWEET!!! I'm thinking of ordering the plans for Mike's 1/4 Camel and also the Replicraft Camel plans. Just doing the research on this project could keep me occupied for the better part of a year! Apparently the Replicraft plans are printed at 1/5 scale.

But I'm also still drawn to the odder two-seaters.

If that's the case Don, you might also want to consider the Nieuport 12. Same basic sesquiplane layout as the later developed nieuport 11 scout but as a two seater!
This would also be one of my future scale candidates as it doesn't seem too complex to build and I haven't seen any kits for this aircraft.
Here are some pics scoured off the web:

I used this technique on my HB-C1. 30# flexible fishing cable worked well(for qtr scale), it's readily available. After the wing is built and finish-sanded, I anchored the end of the cable to the root rib. It is then pulled across the back end of the ribs, and anchored to the tip rib (the TE of each rib is sanded almost to a point). You should be careful not to pull it too tight, just snug enough to draw it up straight. Next, make up some small 'clips' from thin aluminum, these will wrap around the trailing edge of each rib, attaching the cable. Bond with ca or epoxy, clamp with a clothespin.
Covering can be interesting. To avoid a seam at the TE, the wing is covered with one piece of material. I start at the bottom LE, iron the fabric securly and work back towards the TE, being careful to bond the fabric to each rib. The covering is then wrapped around the TE, over the top, pulled snug to the LE, and ironed down. A straight lap can now be cut in the excess, and the edge rolled over the front and securly finished off where you started, making sure you left enough for an overlapped joint. Finish off the tip and root, then it's on to shrinking. Go slowly here, alternate top and bottom, and at different places on the wing. The idea is to heat it evenly. You will soon see how the fabric will begin to pull itself tight at the TE, pulling the familiar 'scallop' shape into the wire. This all sounds awful, but it's actually straight forward and well worth the effort.
A lot of axis designs used this technique, while the British and French seemed to favor wood trailing edges. This was not the rule, but rather a trend. German designs favored setting the spars well forward in the wing, which leaves a long portion of the rib hanging out behind the rear spar. That's why it is important to bond the cable to each rib, to provide some support.
Don, power to you, my friend. With Reeves plans and Replicraft drawings for the Camel, your E-III project will seem like tinkertoys.

John

John, if I were to do a real precision scale version of the Camel it would be a long slow endeavor probably extending over several years. I'd probably spend a year or two just stewing over the drawings and collecting documentation. The thing I don't like about the Camel is that it has virtually no nose moment.

Anyway, I'll have plenty of time to contemplate what's next. I still can't believe I actually finished the EIII.

John. I like the technique. I copied your post to my computer, and will have to try it some day.

So many airplanes, so little time.

Les

Some of the responses are discussing the technique of tubing that was formed to make the edges of flying surfaces on certain airframes. Lots of designs did this., but I understand the quesiton to ask about the scalloped look along the trailing edges of surfaces. It looks that way because there was no underlying structure except a length of wire, around which was bonded and sewn the covering material. You can do the same thing in miniature.

I read John Cole's reply. Sounds right to me at that size and those materials. I don't generally use iron-on covering, and 30# line seems large to me. If he's using 30# metal trace line, one needs to be careful with using any kind of wire or metal framework at right angles to one's radio: it's a giant antenna!

So here's my solution, which also ain't pretty, but works. I use some stuff called Spiderwire, which is a non-stretch fishing line. I dunno what it is--some kind of kevlar, graphite, or other unobtanium. It has a waxy feel and doesn't take any kind of adhesive particularly well. It comes in different weights, but you can't break any of it no matter how hard you try, so there's no reason to get the heavy duty stuff. I use it also for rigging biplanes and pull-pull cables (the "smoke" color is a fair approximation for dirty flying wires!). As John did, lay it across the tips of the trailing edge ends of the ribs. BUT, you need to have the tip of each rib hardened to prevent the line from acting like a knife and simply cutting into the rib end grain. The full size practice was to cap the end of the rib with a metal clip (like a shoe) that also held the wire in place. I use very fine whisker wire to do the same thing. Once the entire trailing edge is draped along the ribs, the ends of the spiderline have to be secured at the root and the tip to keep it from pulling loose under the strain of the shrinking covering. I sew it into the wood, using a piece of a toothpick for a hard point in the root and tip ribs. Then a tiny drop of CyA at each rib t.e., just to tack the wire there. Whew! Covering with silk means laying the excess over on itself to surround the wire. I do the bottom surface first, and overlap only enough to let it grab. The top piece of covering can overlap further, as it won't show as much from the bottom. Take care to make sure the overlap lies as flat as possible flat, as it will bunch up some as the dope cures. Practice on a scrap piece, as this takes some deftness and I ended up ruining my first effort at it! The scalloped effect will occur naturally as the covering shrinks, as John notes. The line will pull in between ribs, but only up to a point. (I tried monofilament fishline, and it was so stretchy that it just continued to pull in, leaving the covering saggy; it didn't work well for me.)

You will think it looks untidy when you first get it done, but, oddly enough, it will have just the right amount of "crudity" to it when the final finish goes on so that it looks like the same thing done on the full-size some 90 years ago. There's a reason for that: they did it this way back then, too! Have fun, especially with fabricating billions of the little wire clips, most of which you will lose in the clutter on your workbench before you can ever grab them with the tweezers to get them in place.

Jim

Jim, thanks for the detail description. It may seem tedious to some but I'd sure rather do that than speed weeks putting 20.000 rivets on a WWI warbird! Have any pix your could share either of the process or any finished planes?

John and Jim,
Sounds like some very interesting tecniquics. I just recently bought the Torrence Dr.1, so it would be a great plane to try it on.
From I'm reading, it should work just as well using iron on or dope on material.
And a couple of practice wing sections would certianly be in order.
Thanks for the info. [sm=thumbup.gif]