FRANK'S 1/2A F4U CORSAIR BUILD

[Frank v B]

Shaping the tail fillets:

1) shaped the inserts with a razor plane
2) I have marked the spacer pieces with black magic marker
3) the two tail fillets finished.  Ta Da!

Total elapsed time for shaping and cutting- 5 minutes.

Frank

[Andy Hoffer]

The fillets can also be hollowed out and used as salt and pepper shakers!!  As shown in the 4th photo, they are conveniently premarked with "S" and "P".  That @Frank v B guy is a master of multi-purpose balsa!! 

Andy

[Frank v B]

Now that Andy has decided he wants both pepper and salt with his balsa dust, we will continue the build....

- installed the servos for elevator and rudder
- filled in the wingtips at the leading and trailing edge... 8 fillers... tedious
- added the landing gear by cutting the groove and drilling the retainer holes
- added the pilot... so the plane flies better.

Sanded everything smooth.  Ready for covering.

Frank

[Frank v B]

Now to answer Glenn's question on colour.  I went to my two books of cool prop planes.

Objective:
- To me a Corsair is best remembered in dark blue.  Preferred dark blue on the bottom as well to make it visible in the cloudless warm summer sky (dreaming!).
- wanted some form of contrasting colour up front.

Found the perfect subject.  It even has an arrow on the starboard wingtip (called "Andy's Arrow") to remind me of the direction of flight.

Frank

[Michael]

Blue and yellow, ... I like it.

[Frank v B]

Started the covering.  Found a new roll of Midnight Blue Ultracote.  Good enough for me.

Started with the wing.  Get the most frustrating part out of the way first!

Step 1- first thing to do when covering the wing is to cover the aileron inside corners with small pieces of covering.  If you don't, it will show bare wood.  Notice in the photo that I pulled the aileron out with the CA hinges attached.  I cover the wing in its entirety first, then use the bare aileron to find the hinge slots in the trailing edge.  Once I have cut those, I can cover the aileron.

Step 2- A normal wing is covered in 4 pieces (2 top, two bottom).  This wing was done in 18 separate pieces because of the gull wing and the round center section on the bottom.  Arghhh!!

Step 3- Had to put the aileron horns on with the servos centred since they are being buried in the wing.  Once in, the servo arm screw cannot be accessed.  Notice that the covering is not shrunk yet.  Never do it until the entire wing is covered.  This way you can control wing warps.

Tomorrow will be spent finishing the wing and ailerons.

There is a finish line.... somewhere.... like there is a Spring... sometime.

Frank

[Andy Hoffer]

There is a finish line.... somewhere.... like there is a Spring... sometime.

Frank

It's in the corn, so don't cross it. Just land short!!   

Andy

[Frank v B]

It is starting to look like an airplane.  Everything is covered except for the elevator and fin/rudder.  Nothing has been shrunk yet.

- have to deal with the tail wheel.  The plans show a fixed tail wheel but there really are only two options: i) a fully operational tail wheel with a tiller bar at the rudder or ii) a castoring tail wheel.  Will tinker with it tomorrow.

- the elevator joiner dowel is covered with carbon fibre and 5 minute epoxy.  I put waxed paper around it and used red electrical tape to hold it over night.  I was starting to get concerned as the motor increased in size and the weight increased.  The elevator halves are held together with a 1/8" dowel.  If it twists under load it will be difficult to handle.... if it breaks, it will be life altering.

Oops.  Forgot to include Andy's salt and pepper shaker in the photo.

Frank

[Andy Hoffer]

- the elevator joiner dowel is covered with carbon fibre and 5 minute epoxy.  I put waxed paper around it and used red electrical tape to hold it over night.  I was starting to get concerned as the motor increased in size and the weight increased.  The elevator halves are held together with a 1/8" dowel.  If it twists under load it will be difficult to handle.... if it breaks, it will be life altering.

Frank

Would 1/8" carbon fibre rod be an option to replace the wooden dowel?

Attentive Student Hoffer

[Frank v B]

Andy,

Yep.... but that would have required thought on my part.     The real problem is gluing the carbon rod to the balsa.  Sometimes the joint is not solid when using epoxy and I cannot use CA.  This whole thing only took 5 minutes and it should be plenty strong.... until the crash investigation report is published!

Here is what I did:
- took the waxed paper off and cut back the excess carbon fibre around the dowel.  First photo.
- applied 5 minute epoxy around the center part of the dowel and wrapped 3 wraps of carbon veil around it. Second and third Photo.
- wrapped a small strip of waxed paper around the dowel and a wrap of electrical tape to hold the waxed paper while the glue cures.

Photos will follow later because apparently you have to charge rechargeable camera batteries once in a while.

Frank

[Andy Hoffer]

Photos will follow later because apparently you have to charge rechargeable camera batteries once in a while.

Frank

Hmm...  This concept may have application to your TX and flight batteries!!!

Andy

[Frank v B]

Finished the tail wheel issue.  Drilled a hole through the bottom and through the stab.  Slipped in a piece of brass tubing and glued it in place.  Bent wire to make the tail wheel assembly and put it through the brass tube.  Bent the tiller arm.
I will cut a slot horizontally through the bottom of the rudder and insert a metal tube so it can slip over this tiller.

The photo shows the tail wheel assembly below the fuselage, the stab and elevator in place, the tiller arm above the brass tube at the top of the fuselage.... and Andy's salt and pepper shakers glued and covered and ready for installation.

Also completed- wing attachment bolt drilled and tapped, ailerons installed permanently, fin covered, fuse covering removed where the fin glues to the fuse.

[Frank v B]

Just attached the fin.  I cut the covering from where the fin needs to be glued, added 5 minute epoxy and used two pins to hold it in place (fore and aft).  Then taped a plastic rectangle to the fin and rudder to make sure the fin is at 90 degrees.  Note that the corner of the triangle has been cut out to allow for the fuselage.

Andy's salt and pepper shakers are glued and heat sealed in place.

[bweaver]

@Frank v B and @Andy Hoffer  Re: Then taped a plastic rectangle to the fin and rudder to make sure the fin is at 90 degrees.  Note that the corner of the triangle has been cut out to allow for the fuselage.

Frank you are much to fastidious.  I wouldn't have cut out the corner of the triangle. I would have cut a slot into the salt and pepper shakers on each side of the fin and used another triangle on the other side to ensure that side was also at 90 degrees too.  Further, making the triangles permanent allows for equal drag occurring on both sides, minimizing the amount of trim you would have to use to compensate for having a triangle on only one side.  And when the plane crashes, the fin will likely remain in place in its 90 degree attitude, saving lots of time on the rebuild.  I hope that is clear. 

[Andy Hoffer]

Andy's salt and pepper shakers are glued and heat sealed in place.

It is comforting to know that my salt and pepper shakers are securely mounted in the safest part of @Frank v B's plane and will provide a visible marker for recovery of the plant plane. I am most honoured to be in the tail gunner position.

Andy