Bought a Brodak Cardinal which has a 54 inch wingspan. I also have the Brodak wing jig which I haven't used yet so I don't have any experience with it. The jig isn't long enough to do the whole wing in one piece so I'm assuming I will have to construct each wing panel individually. My question to the experts out there....how can I attach both wing panels so that the wing remains true? I guess I could shim both panels and use a straight edge to check for alignment but how would you experts do it? Thanks

  What does the Brodak jig use for rods? I have never seen one. First thought is to purchase rods that are long enough. Second thought is to build each half to a certain point, then join the panels using the jig and rods in the center to align the haves, as long as you know you will be able to slide the rods out.

  Welcome to the party pal!!
  HAPPY NEW YEAR!!
  Dan McEntee

Using the jig you have, get each wing half built, then slide the rods halfway into each one and build the center section.

The Brodak wing that I built has 5/16" jig holes.  That's an almost exact match for 8mm carbon fiber tube.  So, find a kite shop (I like Goodwinds) that sells six-foot long 5/16" (0.313") or 8mm tube (or rod, if you don't mind heavy), and use that with your existing jig pieces.

I just used the 8mm tubes and 1" thick aluminum spacer blocks on a flat building board -- that's enough of a jig for me, and I seem to be building straight wings.

The only advantage to using longer rods is you get to splice the spars and trailing edge with scarf joints instead of a butt joint. Not worth the extra expense imho.

Motorman

     Definitely worth the extra expense when it comes to nice, clean joints that are stronger than butt joints. And you can build the wing farther along in one sitting with more pieces assembled to make the structure more rigid before removing from the jig, so it's a time saver.. If you plan on building a number of models, it's definitely worth a few extra bucks.

     HAPPY HOLIDAYS!
     Dan McEntee

I use 32" arrow shafts for my jigs.  Nice thing is that they have a threaded end where the arrowhead screws in.  The ones I have been getting are 8-32 threads.  A short piece of all thread and they make a 64" rod.

Ken

I think as long as I support the middle of the 2 rods, it should work great.

Harold

Absolutely, just don't make the same mistake I did.  When flipping the wing over to sheet the bottom LE one corner of the inboard wing was up so I weighted it down.  Actually what happened was my center support got a piece of scrap balsa under the front and I missed it.  Some warps just aren't removable.  Thanks to adjustable flaps it still flies well but not without days of tweaking and no amount of tweaking can overcome the effect of a warp at different speeds.  It just goes to show you that even after 60 years of building these things you can still make a rookie mistake.  I made two.  Take measurements EVERY time you take it off of the supports and put it back.

Ken

Make sure you level the rods before gluing things. A support in the center is a good idea.

Make sure you level the rods before gluing things. A support in the center is a good idea.

    I use long rods on my home made jig. They sit on three, 1"by2" cold rolled steel blocks, with one in the middle. It's easy to check that the rods are straight along their length by using a straight edge across all three blocks, and then I just set a small torpedo level across the rods and check them that way and make sure the level agrees with each section. Then I just weight the rods down with some other blocks for building.
   Type at you later,
    Dan McEntee

Hi, I've been lurking on here for far too long unsure whether to post or not but when I read this thread thought that perhaps I might have something to offer. My names Ramon but all call me 'Tug'. I'm 77 and have been interested in building stunt models since I was fourteen.

This is not to teach Granny how to suck those eggs as I'm well aware of the prowess of all on here but this may be of use as an alternative.

If you take a look on the Barton Forum here http://controlline.org.uk/phpBB2/viewtopic.php?t=6631 I covered a different method of setting up a simple but accurate wing building jig with easily available materials. It's been proved over many models now and has now 'advanced' from bespoke to fully adjustable to suit all wings (with straight LE's). Due to a long break from the hobby this version was only recently tested on building a Coy Lady and a Tucker Special  http://controlline.org.uk/phpBB2/viewtopic.php?t=16579.

Hope it is of use to someone - it's not a 'better' system but it is a way of dealing with getting a true wing without elaborate methods.

Best Regards - Tug

 

Glad to hear that you found something of use Dave.  The method evolved over several years the whole idea to be able to build a traditional balsa wing as truly as possible and without twist about it's central plane. The whole object was to come up with something that gives the result desired  without recourse to elaborate kit.

The spar slots were originally cut as you describe as to begin with the wing ribs were assembled on a carefully positioned spar but despite the care on a tapered wing there was always the possibility that an error could be built in (from the front view) relative to the TE and LE Eventually, by supporting the ribs on their centre line the spars slots done in position match the spar and the spars have an equal taper to the tip.

I perhaps should point out that I build all wings in the same method, changing construction from the plan if necessary - the T'Bird wing for instance has the spar position much further back - as designed the spars are much further forwards and require not only bending to the curved front view profile but twisting in section to accommodate the change in angle as they match the rib profile. Must stress I'm not disagreeing with Bob Palmer's design here just my way of trying to take out all building stresses where possible.

I know that a couple of Barton members have tried the method with success - as said it's mentioned purely as an alternative to more recognised method but I hope its of interest to those who look in

Regards - Tug

PS Here in the UK 'Tug' is synonymous with the surname Wilson though why I have no real idea 

I’m also going to build the same plane with a wing jig from Great Planes.

The jig itself comes with 1/4 inch steel rods meanwhile the holes on the ribs are 5/16.
I have bought the 5/16 steel rods and it fits perfectly although it’s a bit hard to slide and spread the ribs — this actually makes me worry to remove the rods when the wing is set.

Should I use the 1/4 or the 5/16 rods?

Thank you!


Kafin

If I'm not mistaken, I remember seeing a Windy video where he chucked up the rods in variable speed drill and pulled them out! 

Dennis

I have taken the rib and slid it over the rod a few times to loosen it up a little bit

Thanks for the tips guys.

The jig is now ready to use.

Any pro tips on the gluing order?
Which one has to be the first, second, and so on?
- Leading Edge
- Top Spar
- Bottom Spar
- Trailing Edge
- LE & TE Sheeting

Best


Kafin

I added a tip-up action to mine so I could easily do the bottom spar.

No big whoop, just a couple of bolts.

Thought it might be of interest to show the latest wing built as indicated on the link
Regards - Tug

Nothing shows up on my browser - edge.

Ken

Nothing shows up on my browser - edge.

Ken

   I'm using Chrome and nothing here either.

Hi Guys - Though I am well familiar with posting images elsewhere it's been a while since I uploaded any pics to Google pics and created a new album. I just remembered that I have to make the album public  .

Can you tell me if you can see them now please as hopefully you should be able too

Tug

   Remember using longer rods make sure no glue gets on them.   When the time comes a little twisting of the rods will help them pull out easier.

    Hook a drill to them and spin them at very low RPM while pulling!

    Brett

A fixture that aligns the LE & TE is a correct fixture.

A fixture that aligns a row of holes can make an accurate line of holes, but not necessarily a correct assembly.

Actually there is zero error in lining up the LE and TE if you use a "rib jig" to locate and punch the rod holes. It's a sliding fixture that captures the nose and aft end of each rib... the holes are located and cut in perfect "assembly" alignment. It excels in tapered wings like a TBird. If someone is using a Great Planes type jig with scratch built ribs, cutting the rod holes wrong could make a case for LE and TE alignment...but as long as the ribs are cut accurately it's a non issue when using an ajusto jig rib jig for rod holes.

I also have and use the A-Justo-Jig.
In addition to what BillP said above, in actual practice, when I come to attaching a (sub) leading edge and trailing edge (spar or sheeting), it is easy to easy to visually ensure that these LE and TE pieces are centered, height wise, on the rib LE and rib TE.   For the sub LE, one could mark a line on the inside vertical surface to identify the midpoint and match this line with mid points draw on the sides of rib LE. 

I'm currently building a Brodak Yak-9 OTS kit and have the Brodak wing jig. The wing is 40" long, but the jig aluminum rods are only 36". I found some 8mm OD CF tubes that were 1m long (approx 40") at a local hobby shop that allowed the wing to be built in one piece. It worked quite well.

If I build a longer wing project in the future, I'll find longer 8mm tubes or use some of the alternat jig suggestions noted herein.

My model airframe is complete and ready to start the covering/painting process.