OK, here is my story... I had so much trouble with the vertical stabilizer fiberglass (FG) tips, I ended up needing to buy another tip rib because I forced the FG tip in between the rib and the skin. Just used too much pressure, I guess. Anyway, it was too tight, but I finally got it.  I was hoping that the horizontal stab FG tips would go a little smoother, but from the previous page, you can see that it did not go as smooth, in fact, they are even tighter than the VS tips!  This was the reason  I decided to just mount them outside of the skin, using aluminum strips for the mounting surface.  Well... after searching the archives at SonexTalk, I came across another idea which seems better then using the aluminum strips.  The plan now is to make another tip rib and have it mirror, and then mount it, to the original tip rib.  This new rib, will be my new mounting surface for the FG tips. 
Since I really did not want to buy anymore ribs from Sonex, and my father kept saying it will be a lot harder, if not impossible, for us to make our own, I decided I will give it a shot!  I went ahead and took pics of this process. I hope it works!!
June 29, 2007
Horizontal Stabilizer
Ohh yeah... one more thing. In retrospect, I might not have had all these problems with my FG tips if I had installed them the same time I was drilling the skin to the frame.  Currenty,  I am trying to install them after my frame and skin are already riveted together.
Remember, I am not a scratch builder! And, I have never done this before, I am kind of just "wing-in" it.  Traced full size plans onto paper, then will use MDF board to make the forming block from.
Used glue to hold the paper to the MDF board
Cut MDF board into half and doubled it under my pattern board. Made drill marks onto my pattern, located from the original tip rib.
Used wood screws to hold the two pieces together. The 1/4" "other" holes will be used to clamp the two boards together for the bending process.
Still together, the boards were cut on the bandsaw to rough shape.
Sanded "to-the-line."
On the top Right corner, you can see my "round-over," just hit it with sand paper. The radius calls for 1/16". I just guessed
Next, I will sand an angle on the forming block to allow for "spring-back," on the flanges so they will "spring-back" to near 90 deg once formed.
The aluminum will be bent over the Right side corner of the formed block. You can see the round-over and the taper for the "spring-back."
I did not have the right sized sanding drum or I would have used that for my fluted cut-outs. Instead I used a file... not too happy with the results, but at the same time, I do not know exactly what kind of cut-out to make on this, or how important, or how precise it needs to be.  The plans call for 2 fluted areas, but the piece they pre-made had 3 fluted places... well, 6 total, 3 on each side. I opted to put 3 cut-outs for my fluted areas.
The forming block ready to go!  Yeah right.. At least I am hoping it is ready to go.  I am sure the scratch builders are laughing hysterically at this work of art!
Flanges are suppose to be 1/2". I made the drawing around the rib a little larger than that... 9/16"  This block is what I made so the line would be even, if nothing else, around the entire rib.
Made a rough cut out off the line. Will sand up to the line with the sander. Watch those sharp edges!
Sanding to the line with the sanding belt. This is all I got done tonight. Probably 3 hours worth of work for this amateur. Next comes the bending.