Stuka Stunt Main Forum · 20 of 20 known posts recovered
Bill
I build more planes than I fly, collect more engines than I'll ever use. That about says it, right?
It depends. Adjust-O-Jig (and a couple of others) use 1/8" steel wire. Al Rabe uses (or used) 3/8" dia. aluminum tubing for the Mustang and Bearcat. Not sure just what he's doing now. Al ? ? ? Here's one of many sources for aluminum tubing:
http://www.onlinemetals.com/merchant.cfm?id=947&step=2
Price for the 3/8 OD x .065 wall x 6' is $10.17 + shipping.
I have both setups. The aluminum tube approach is probably the more accurate of the two. You can "boresight" the tubes, shimming as necessary, and when all the little "interference rings" are axial, you KNOW the tubes are straight.
I haven't used it yet, but I also have Tom Morris' New Millenium building board and jig blocks. I'm expecting to enjoy this one.
Ralph Wenzel
Larry Richards http://richardskits.net
Matt Neumann
SAVE ALL THE PIECES-Phil Brown
These were 3/8 aluminum rods about 5 to 6 feet long not the thin stuff you are probably thinking of. Ture, I would not use them as a baseball bat but once you get them rubber banded down to the jig they were plenty strong.
Matt Neumann
Big Bear <><
Character: It's what you do when no one else is watching.
Bill
I build more planes than I fly, collect more engines than I'll ever use. That about says it, right?
I forgot.......... I have had some 6 foot long 3/8ths" steel rods for several years now. I built a couple of wings on them, but I just use the arrow shafts now. They don't sag under their own weight and are easier to set up.
Big Bear <><
Character: It's what you do when no one else is watching.
Bill
I build more planes than I fly, collect more engines than I'll ever use. That about says it, right?
Your local Lowes or Home Depot store should carry them.
Check in the specialty hardware dept. but don't get the aluminum rods (IMHO) they're not stiff enough.
http://www.builtrightflyright.com/ryan1/ryan1.htm
Thank You and God Bless
Walter Umland
aka / builditright
visit my website at http://www.builtrightflyright.com
you can e-mail me at [email protected]
3/8" is a big hole in the rib. OK for big planes, but way too large a hole for a smaller airfoil.
Rigidness is only an issue if you want only two supports at the ends.
I'm thinking that 1/4" or even 1/8" would be fine if you design in FOUR support posts: the tips, plus two evenly placed intermediates.
I already have 1/8" holes from the stack-sanding process, so inserting piano wire would be easy.
Bruce
Bill
I build more planes than I fly, collect more engines than I'll ever use. That about says it, right?
When it comes to building techniques, we seem to have a thousand experts who seem to value simplicity and cost above quality and accuracy.
I've built a lot of wings on 3/8" tubes, in fact I originated that wing building method when I published it in the first Mustang article thirty eight years ago.
I do not recommend steel tubes. they are heavy and tend to droop from their own weight. Stainless steel is even worse. Stainless steel tubing is very soft and bends easily, yes, bends, not flexes. I built one wing on stainless when my aluminum tubes were in Richard Oliver's wing in Houston. My usual supplier of aluminum tubes was out of stock and it was stainless or delay. I built on the stainless after trying first to straighten them. I swear those things would take a bowed set from just carrying them around. I got the wing built, with difficulty in keeping the tubes straight and then I trashed them. They weren't worth giving away.
[photo not recovered: 4491720207e5d68d.jpg]
I consider at least one center support absolutely necessary to keep the wing from drooping in the middle. For years, I used two center supports but decided twenty years ago that one was enough. I verify the alignment of my tubes by "bore sighting" them periodically while I build. It is easy enough to pick up a thirty second inch of misalignment. If you don't think so mount up a set of tubes and stick a 1/32" shim under the center support and bore sight. It is this capability to determine accuracy that I value in construction. Arrow shafts may work as jigs and are cheap but you lose that bore sighting capability which is enhanced by the shiny interior of the metal tubes. When you know the jig is perfectly level, it is stunt heaven to build with laser cut ribs for perfect alignment of the wing's surfaces.
As for size, 3/8" is large enough to have the necessary level of rigidity and small enough to build thirty five size airplanes.
For fifteen years I built on a trusty set of tubes having .049 wall thickness. These were lost in storage when I moved to Saudi Arabia to fly for Saudia. I think this is a minimum. I have also used .058 and .065. My current set is .065. The thicker sizes cost more and .035 is too weak. I used to be able to get 12' of aluminum tubing for about $10 (forty years ago). My last set of .065 cost $25. If they are taken care of, they will last forever. Here in Texas, when somebody needs a wing there is usually a set somewhere to be had. I have built wings on tubes belonging to Frank McMillan, Richard Oliver and Brad Walker. I have also loaned tubes to other builders when my set wasn't in use.
[photo not recovered: 449172530b97a058.jpg]
When building, the jig tubes stay in the wing, not only until it is completely sheeted, top and bottom, but until the airplane is fully assembled using the wing jig as just one physical element element of the set of alignment jigs. To assemble and align my airplanes; I use the wing, in its jig, the fuselage in its jig and separate jigs for the horizontal and vertical stabilizers. There are also jigs for aligning the flaps and elevators. Using a set of jigs, I am able to build a straight enough airplane that they never require "tweaking" of the flaps or adjustment of the elevator neutral or pushrod length.
Al
Most people would have just built each wing separately, then join them with dihedral, but this is neater by far.
[photo not recovered: 4491a4b44cfe324d.jpg]
A thought on the dihedral wing alignment above in Al's pic. If we stack carve the ribs with the dihedral offset built into the stack, all we have to do is drill the jig rod holes whilst the ribs are still bolted into the stack.
I bet there are many who have never stack carved a set of tapered ribs or have got out of practice with all of this laser cutting these days. How lazy have we become! Ah well, it's good to dream of those days when we did all of these things before CAD and laser became fashionable.
HH
This is the first tube type wing jig. I originated the jig in 1966. Actually, it was the need for a jig which could accept dihedraled wing construction which prompted the construction of that first jig. It was published in the Mustang article in 1969. This is a photo from that article.
[photo not recovered: 4497f75b37b32aaf.jpg]
As for the dihedral, the first wing, in the photo above, and nearly all that followed were built with dihedral. This was decades before computer plotting of laser cut ribs. The ribs were stacked, then cut and sanded using aluminum root and tip templates. They were then placed, one at a time, under a clear plastic template on which I had etched parallel vertical and horizontal lines. For example, for rib number three, it was only necessary to place the rib on the third line up and third line over then punch the rib jig holes. The holes were cut with sharpened 3/8" brass tubing. It was surprising just how accurately aligned the ribs were when using this old technique. Three NATs winning airplanes were built this way.
This is how I built tapered, dihedraled wings forty years ago.
[photo not recovered: 4497ff8477da4dce.jpg]
[photo not recovered: 4497ffb57850547a.jpg]
[photo not recovered: 4497ffe378ec1fc9.jpg]
[photo not recovered: 449800637f0b95f2.jpg]
I used the "bird's mouth" on the front of the rib for alignment under the plastic template, and there was a saw cut on the trailing edge of each rib for alignment. The saw cuts can be seen on the aluminum templates and the fourth photo of the completed set of ribs.
Al
HH