If you're interested in WWII warbirds, Dave Diels makes some of the nicest kits on the planet and I highly recommend them.  He fills his kit boxes with not only a wonderful design and plan but he's a modeler and selects first-class balsa, tissue, and decals so when you buy a Diels kit you can feel confident using the materials provided.

With the exception of the root rib, ribs are all cut from 1/32" balsa.  John Ernst has had some problems in the past with these thin ribs buckling when the tissue is shrunk around the wing and with that as a 'heads up' I decided that I should give some thought to NOT having that problem.  If I were scratchbuilding I would have just made them all from 1/16" balsa but I saw this as an opportunity to investigate whether significant weight could be saved while also ensuring sufficient structural integrity  What follows are the steps of that journey, the end results and some analysis.  

 

A number of 'holes' are indicated on the ribs.  Removing these bits creates "lightening holes" which, according to their name, are supposed to provide significantly less mass in the wing.  Gotta be a good thing, that... if it's true.

 

Making these holes is very easy if you have some brass tubing, sharpened simply by thinning the edge surrounding the end of the tube.  A couple spins with these sharp tubes and you have a nice, neat hole.  It took me about 10 minutes to generate the required holes in the 16 ribs.   

 

The end result is a bunch of ribs with a bunch of holes in them.  The interesting thing is their weights before and after the treatment.  

 

Weight before "lightening": 1.05 grams  

Weight after "lightening": 0.85 grams  

 

With a savings of 0.2 grams (or about 20%), I'd say these holes live up to their name. 

 

To improve stiffness, however, we've got to add some weight in the form of 1/16 x 1/32 sticks running between the leading and trailing edges.  Here I've just dropped a couple magnets onto each rib to hold them flat while I glue those reinforcement sticks in place.  This does make the ribs quite stiff and I think they are far less likely to buckle than if used without the reinforcements.   

 

Here are the completed ribs.  Total weight gain from the addition of stiffeners was 0.15 grams.  

 

As I said at the outset, normally I'd just use 1/16" ribs and be happy as a clam.  But here's a bit of a comparison between the two approaches.  I make the assumption that 1/32" ribs weigh half as much as 1/16" ribs.  

 

1/32" ribs with holes and stiffeners: 1.0 grams  

 

1/16" ribs (no holes): 2.1 grams  

1/16" ribs (with holes): 1.7 grams  

 

This is a fairly signifcant savings to me and would certainly allow the addition of small gussets at the rear of each rib as an additional protection against rib buckling.  

 

 

Building the wings was straightforward and went quickly once the ribs were prepped.

 

The stabilizer is more complicated than most.  Each front/back stringer has a 1/32 x 1/16 cap added to it and these are sanded to an airfoil shape.  Each stabilizer half has a trim tab and because the stabilizer must plug on either side of the fin/rudder assembly there is a small box created in each half that a 1/16"sq piece fits into to hold the two halves together.  It works really well.

 

I decided to cover all the flying surfaces before moving on to the fuselage.  I used white Esaki as I plan to paint my Wildcat with acrylics.  

 

I finally got to start on the fuselage and this is what it looks like as I'm about ready to pop it off the board to attach the formers on the other side of the crutch.  Before doing so, I'll add some supports for that process.