Sunday, January 16, 2011

Landing Gear Bulkheads

A major step in preparing the landing gear bulkheads is the creation of 4 hardpoints (LG-1, LG-2) that get attached to the foam bulkheads before they get glassed.  You do this by laying up enough fiberglass to create a 1/4 inch plate of fiberglass in an 8x12 rectangle.  The plate is 1/4 inch thick to match the thickness of the foam where they will be attached.  Below is the cured 1/4 inch plate after trimming off the excess glass cloth.

The task took me 23 layers of glass and 4 hrs just to get it all layed up and wet out.  Once it's layed up, you weight it down with about 60lbs to form a nice 1/4 inch plate when cured.  The thicker black lines you see in the picture are just sharpie marks I had on some of the glass cloth.  The thinner lines are the outlines for the parts I'm making.

Once cured, you trace the shapes of the parts and cut them out with a table saw, sabre saw, etc.  Above are the finished parts ready to be epoxied to the foam part of the bulkhead to form the full bulkhead.

Below, cutouts are made in the foam bulkheads and the hardpoints attached.  Finally, each bulkhead will be fiberglassed front and back and installed when the fuselage is built up.


Fun With Tail Draggers

Saturday was the first EAA Chapter meeting of the year and I was invited to spend the afternoon with my neighbor an his friend at his private airfield.  This was a 2000 ft grass field once used a as a cropduster strip.  He has two hangars that house several of his own aircraft as well as some of his friends.

The best part was the great man cave attached to the hangar.  The gentlemen is a retired BGen from the USAF and had a 3 story control tower-like hangout full of memorabilia, a kitchen for snacks, drinks, etc.  It was great.  I tagged along in a Bakeng Duece, a homebuilt open cockpit monoplane, owned by a former fighter pilot and his neighbor.  What a blast I had!  It was cold...but worth every minute of air time I got.  I've informed the spouse that this is my new favorite hangout.  See the slide show below.


Sunday, January 9, 2011

If at first you don't succeed...

Well, after inspecting my instrument panel (IP) I decided there were too many air bubbles in the layup and I wasn't happy with it.  I thought of taking to a friend to look at in the hope he would say it was ok, but after more thought...I knew I just wouldn't be satisfied.  I knew I could and must do better getting the air out of the layups so I decided to redo the IP.  You can see the worst of it in the pics below.

So while watching the Saturday Wildcard Football games, I traced and cut out a new IP which will be glassed in the coming week...but only after reviewing all the plans info and Rutan video on glassing technique.

As I think about my technique and review the lessons, I believe I have a couple of problems.
  1.  I'm too slow.  I need to get the epoxy on and spread much quicker while its still warm and able to wet out quicker.
  2.  I realized I haven't been using a brush to stipple the layup and help bring air to the top.  I've been relying on the squeege for all the air removal and perhaps it just can't get it all.
  3.  I'm not using enough epoxy up front to wet out the layup.  I need to pay attention to use more than I need up front until it's all wet out and know that I can remove what I don't need.
  4.  I have to work harder to find the air bubbles during the layup...perhaps a work light that I can use at different angles to help find them all.

We'll see what happens...