A simple wing jig...

[DB2]

A friend agreed to fly an Agwagon after the horizontal stab was rebuilt in a homemade "jig". The "expert" A&P had screwed up every angle and spec imaginable with his little jig. My friend - a 20000 hr, former Vietnam (Army) pilot - told me it was the scariest flight of his life.

[stumac]

Good job Chuck! Look at the s**t you stired up. Now you got Rich talking about jigs and stuff. Pretty soon he will be talking about building P-38's.

[RMAllnutt]

During WWII to speed up construction and deal with a decline in experienced workers aircraft were built in smaller pieces. Such as a left and right side of a fuselage in separate fixtures. Then brought together in a master assembly fixture. The parts were less complicated to make and easier to assemble with less experienced workers building the same high quality product.
Rich

That's certainly true of the corsair. The rear fuselage was made up of many different spot welded panels which came together around the longerons, and three or four major bulkheads. Jigs are not easy at all, unless you have a straight part to work from as a guide for locating the mounting points...

Cheers,
Richar

[51fixer]

The Book is-
Picture History of WWII American Aircraft Production
By Joshua Stoff
ISBN 0-486-27618-X
1996
258 Photos
8 7/8 x 11 3/4 Paperbound
Stoff was Curator at Cradle of Aviation Museum in NY

Stu- Now don't get me going. I started on the West Coast and had to go all the way to the East Coast when you invaded the West Coast from the East Coast. I think we are even.

Rich

[stumac]

Yes they are easy all you need to do is ask Chris. It's just "A LITTLE" bit of welding. He has talked on the internet loads of times about them so he can probably do them in his sleep now.

[Rossco]

Get it level,get it square and keep it there.Your best friend is an accurate tape measure in jig building.Be careful with welding,steel moves around heaps with welding if you don,t preset it,brace it or post set it.Lazer levels,adjustable feet anything you can do to keep it all in line.Here is our fuse jig with the frames just dummied on.
http://3.bp.blogspot.com/_Q0UJnvCHfoI/S ... 09_624.jpg

[t28pilot]

Hey Stu, If Im not mistaken you shot the first one accross the bow...

There you go! Spoken from someone who really knows. All you have to do is a little welding and bingo you have a wing jig. Then after the little bit of welding all you do is a little bit of riviting and you have a new wing. Isn't that how it went for you Chuck? It's pretty easy.

Nice Job stiring it up !!
My point of my long winded story was talk is cheap. All those Monday morning QB's make it sound like everyone does it so quick and easy all the time. Very few really know the details or the hard work.

[Tulio]

There is nothing like reading it, from people who actually do know about a given subject, huh?

Thank you for the information you guys have provided, the thread so far has been very illustrative.

Saludos,


Tulio

[t28pilot]

You bet Tulio. Always good to hear from you !
Hey Stu, do you think Rich will have us retore him a P-38?
What do you want the Fuselage or the wing? I could start with the wing ! I have this simple little wing jig I built after dinner one night. Just need to redo it for the correct attach points, dihedral, sweep, washout, closeout panels and whatever else we can think of over a case of beer.
You could weld up a simple fuse Jig right??

Chuck

[51fixer]

Guys, your forgetting something.
Simple and Lockheed don't go together.
Besides, the real bad thing is when the jig falls off the back of the truck as it is moved over to the storage hangar. It left a mark in the asphalt and wasn't ever used then.
Rich

Last edited by 51fixer on Mon Aug 17, 2009 9:59 pm, edited 1 time in total.

[Cvairwerks]

Heck Chuck: If it's that simple then I wonder why we have about 400 people dedicated to designing, building and verifying tooling at work

I guess I could be pretty good at it too, as I pulled out my 200+ page Optical Alignment training manual. I figure I can read it and get the technique down in about an hour since you can build that wing jig so fast.

On the serious side of things, a simple mislocation of a minor part can cascade problems way beyond what you think. I've had problems where a bracket being out of position as little as .075" caused problems with the install of fuel tubes whiich resulted in a problem with some sensing tube that in turn caused some problems with fouling between sense tubes and hydraulic tubes. By the time the problem was caught, it took almost a week of production time to fix and we scrapped several thousand dollars worth of tubes and fittings fixing the original problem. Yes, it was a tool problem that allowed a locating tool to be placed inside a pocket step rather than against the bulkhead flange. It only took a slight change in the tool to eliminate the problem, but by the time it was found, there were several a/c that had the bracket mislocated.

There is so much forethought and understanding that goes into making jigs and fixtures, that if you don't take the time and effort to do it right, you either spend a lot of time reworking or remaking parts or, in the longrun, you maim or kill someone because you inadvertantly altered a critical element in the design and engineering analysis.

[mustanglover]

Guys, your forgetting something.
Simple and Lockheed don't go together.
Besides, the real bad thing is when the jig falls off the back of the truck as it is moved over to the storage hangar. It left a mark in the asphalt and wasn't ever used then.
Rich

No joke.

First time we removed the leading edges off of the T-33, we all kinda just stood there staring at the main spar going........WOW in a soft voice.

Of course who else holds the entire leading edges on with a piano wire but Lockheed.

[RMB]

Of course who else holds the entire leading edges on with a piano wire but Lockheed.[/quote]

NORTH AMERICAN on the F-86 did,

[51fixer]

Guys, your forgetting something.
Simple and Lockheed don't go together.
Besides, the real bad thing is when the jig falls off the back of the truck as it is moved over to the storage hangar. It left a mark in the asphalt and wasn't ever used then.
Rich

No joke.

First time we removed the leading edges off of the T-33, we all kinda just stood there staring at the main spar going........WOW in a soft voice.

Of course who else holds the entire leading edges on with a piano wire but Lockheed.

T-33- now thats the modern stuff.
Look at the gear door hinges on a P-38. Or the little hyd actuator to latch the front of the nose gear door. Or it takes more hyd pressure to pump the gear down than up. Or they use more of there own pulleys than they do AN. Each flap (there are 4) is like rigging a complete aircraft. After Tony LeVier lost a canopy during high G pulls, (upper canopy had pins for and aft to open canopy up to the side. Receivers for the pins were on front and rear canopy bows. Under high G the nose flexed enough to open up and allow the pin to pull out and depart. That'll get you attention.) Redesign of hinge and locks took place overnight and many thousands were produced with a homebuilt looking canopy system.
Rich

[stumac]

The truth of the matter is that Rich allready has restored a P-38 (or at least he was very instrumental). When we worked at Pacific Fighters together he would tell me a lot about that airplane. I think we are better of sticking to North American products (from what I have heard). Besides Rich has an airplane he needs to build and he has a bad habit of actually looking at the pieces he is working on and finding problems. Dammit Rich what did you find broken today!