Vertical Stabilizer, Epoxy On Vacation

Looking forward to giving my epoxy skills a rest. I'll be focusing next on the center wing sections, so it will be awhile before I'll need to indulge again.

Now that I've completed the rudder and horizontal stabilizer, the vertical stabilizer should be a breeze, right? Well, yes, it was getting easier.

Garage tech indeed.

Fitting the cross braces amounted to aligning the foam with small pencil marks and using my thumbnail to score a line. Cutting with a bare hacksaw blade, a hair oversize, then bringing down to size with a 100 grit garnet paper sanding block.

As learned previously, I layed-up the short brace pieces of fiberglass tape first, then glued the longer pieces over them. I also made use of the microballoon filler after the initial gluing. Also, paste waxing the melamine work surface worked like a charm in resisting any stray epoxy.

The top and bottom are coated with epoxy to resist the eventual melting effects of the Dacron covering chemicals.

High tech, it ain't.

Holding off on drilling holes until ready to assemble.

Hanging from ceiling makes placing fiberglass tape much easier.

Parts, Rudder and Guard Dog

Temporary bolt aligns parts for drilling.

Never succumb to the temptation of removing drill shavings by hand from the spindle while it's moving! Something I learned the hard way about forty years ago.

The component parts collection is growing (below), so I decided marking each and every part with a drawing page number and ID, would help later on.

Marking parts will help later, right?

While weather still permits, my unheated, one-car garage makes an excellent place to do epoxy work. Especially since my wife prefers not to have the house at a temperature that curing epoxy likes - 80° F. 

Guard Chihuahua keeps unauthorized insects out of the garage workshop!

Clear shipping tape keeps epoxy from sticking to the work surface. In the image below you can see my solution to the problem of needing a small, light-weight clamp for the foam: a couple of pieces of sawed off hardwood shim and a random carriage bolt with two nuts.

I later discovered that paste wax applied to the melamine work table surface works well for keeping epoxy at bay.

Gluing rudder braces and ribs with 'shim' clamps.

Fiberglass tape and epoxy layup complete. Some lessons learned:

1. Rough up aluminum-to-glue surface with 100 grit sandpaper all the way around the tube before gluing the ribs and braces.
2. Let the continuous fiberglass band overlap by about an inch. This keeps gravity from attempting to detach it from the foam.
3. Wear breathing protection and gloves if you're sensitive to epoxy. I discovered that I am, probably from working with it over the years.
4. Use microballoon filler mixed into the epoxy to approximate a peanut butter consistency. Works nicely to fill gaps that are inevitable when making non-precision cuts with a handheld knife or hacksaw blade. Only regular epoxy for the fiberglass tape.

Rudder almost ready for covering.

 

Rudder Rib and Brace Assembly

 

The aluminum rudder frame has been acetone-cleaned, 80 grit sanded and re-cleaned in preparation for Aeropoxy attachment of ribs and braces. Clear shipping tape was used on the table to prevent sticking, though I've read that two coats of paste wax on the melamine surface will yield the same effect.

Dry fit prior to cleaning

The foam is easily sanded by wrapping sandpaper around a tube to create the groove needed to mate with the rudder torque tube and trailing edge tube.