Vertical Stabilizer
As with the other parts of the tail, I drew the part out full size onto the table, then screwed the blocks on and started cutting tubes. Several high time Kolbs had developed minor cracks in the tail-post tube where it slides onto the white, steel tail-post provided by Kolb. Looking at the design, it seemed that the tube got all the twisting forces applied to the short engagement of the tube over the tail-post. To remedy this I nested two tubes inside the tail-post tube. The inner tube slides inside the steel tail-post, the middle tube is the same size as the tail post, and the outer tube slides over the rest, giving 20 some inches of engagement providing much improved stiffness, while spreading the twisting loads over the length of the tail-post.
Making a couple of intricately shaped gussets to join disimilar sized tubes. Note the dark colored tube in the right-side of the picture: Many builders substitute chrome-moly to strengthen the tail wheel support. I chose to do the same.
This is a picture of the top of the tail-post tubes. Three tubes nested together. They will be cleaned, alodyned, painted, and slid together before the paint dries for the final assembly. This provides a good load bearing structure to prevent cracks, and I suspect, allows the entire length of the tail-post to carry the loads formerly carried by one end only.
Another view of the tail-post tubes clecoed together.
Top half of vertical stabilizer slid into the Kolb provided, powder coated white, tail-post.
