The vertical stabilizer skeleton is fully assembled and riveted. It now awaits the riveting of the skin, which will happen when I get another set of hands. Though I could do it myself, I figure four hands would mitigate skin denting risk.
The VS-01401 doubler is attached by six AN426AD3-3.5 and four AN470AD3-3.5. I chose to back rivet the flush rivets rather than squeeze them as it has been my experience that thin parts can be distorted when rivets are squeezed in them, especially when the shop head is on the thinner side. Back riveting would help minimize that effect, and it did so wonderfully. My tungsten bucking bar was just the right height to facilitate the process. I did squeeze the universal head rivets (not shown) since I didn't have a rivet set for those guys and I have the right squeezer die due to an unrelated oversight with the wings.
The rear spar has a doubler which includes a suite of flush AN426AD4-6 rivets to accommodate the attachment to the tail. I wanted to buck these rivets to ensure their heads sat flush as sometimes squeezing flush guys can leave the heads ever so slightly proud if you're not careful. I decided to try to back rivet these, having never done so with size AD4. Turns out it's easy to clench the shop heads over on such large rivets when back riveting so I resorted to squeezing many of them anyway. However, not before I had to drill out two bad shop head rivets. Here are the shop heads of the two rivets I removed. I slightly enlarged one hole, as is obvious, but it was manageable. The non-uniform diameter of the shank explains why I had to drill through nearly the entire shank to get the heads out.
And the rear spar with its doubler and rudder brackets. This was prior to the removal of the two rivets above. See if you can spot them. One is easily identifiable if you look carefully. The other you probably couldn't find without a closer image.
Here are two views of the assembled skeleton. For those that are familiar with the plans, you'll notice that it calls for the skin to be riveted to the ribs and front spar prior to attaching the rear spar. My bad. Continue reading below to learn more.
As I was working through riveting the skeleton assembly, I noticed that the plans call for the middle rib to attach to the rear spar by LP4-3 rivets. I couldn't imagine why that was necessary. I could easily squeeze AN470AD4-6/4 for the lower rib. I figured perhaps Van's was just making it easier for the builder, but I of course knew that the pop rivets weren't as strong and they introduce dissimilar metal contact (I lack the knowledge to truly know how much of an issue that might really be).
So I went ahead and deviated from the plans, putting in the two AD4-6s and one -4. Later that night, with my proudly completed skeleton beaming its greatness to the remaining unfinished empennage kit, I realized that the plans call for the rear spar to be attached after the skin is riveted everywhere else to facilitate access to the middle rib flanges. Oh no! But, turns out, it isn't that big of a deal as I can easily access the rivets on the middle rib even with the rear spar attached. In fact, I wonder why the plans took a more cautious route, especially considering the "fun" time with all of the restricted access when riveting the bottom skins to the wings.
Finally, the rivets attaching the bottom ribs to the front spar are very, very difficult to set (if pop rivets were needed anywhere, this would be the place). It is possible to get a squeezer in on the rivets, but it requires deflecting the front rib upwards, which separates its flange from the spar. So I went ahead and bucked the two lateral rivets to make sure the flange was locked down and flush on the spar. I used my tungsten bucking bar, well taped, with my double offset rivet set. Then I squeezed the middle rivet, as bending the rib to provide squeezer access would no longer deform the flange.
The VS-01401 doubler is attached by six AN426AD3-3.5 and four AN470AD3-3.5. I chose to back rivet the flush rivets rather than squeeze them as it has been my experience that thin parts can be distorted when rivets are squeezed in them, especially when the shop head is on the thinner side. Back riveting would help minimize that effect, and it did so wonderfully. My tungsten bucking bar was just the right height to facilitate the process. I did squeeze the universal head rivets (not shown) since I didn't have a rivet set for those guys and I have the right squeezer die due to an unrelated oversight with the wings.
The rear spar has a doubler which includes a suite of flush AN426AD4-6 rivets to accommodate the attachment to the tail. I wanted to buck these rivets to ensure their heads sat flush as sometimes squeezing flush guys can leave the heads ever so slightly proud if you're not careful. I decided to try to back rivet these, having never done so with size AD4. Turns out it's easy to clench the shop heads over on such large rivets when back riveting so I resorted to squeezing many of them anyway. However, not before I had to drill out two bad shop head rivets. Here are the shop heads of the two rivets I removed. I slightly enlarged one hole, as is obvious, but it was manageable. The non-uniform diameter of the shank explains why I had to drill through nearly the entire shank to get the heads out.
And the rear spar with its doubler and rudder brackets. This was prior to the removal of the two rivets above. See if you can spot them. One is easily identifiable if you look carefully. The other you probably couldn't find without a closer image.
Here are two views of the assembled skeleton. For those that are familiar with the plans, you'll notice that it calls for the skin to be riveted to the ribs and front spar prior to attaching the rear spar. My bad. Continue reading below to learn more.
As I was working through riveting the skeleton assembly, I noticed that the plans call for the middle rib to attach to the rear spar by LP4-3 rivets. I couldn't imagine why that was necessary. I could easily squeeze AN470AD4-6/4 for the lower rib. I figured perhaps Van's was just making it easier for the builder, but I of course knew that the pop rivets weren't as strong and they introduce dissimilar metal contact (I lack the knowledge to truly know how much of an issue that might really be).
So I went ahead and deviated from the plans, putting in the two AD4-6s and one -4. Later that night, with my proudly completed skeleton beaming its greatness to the remaining unfinished empennage kit, I realized that the plans call for the rear spar to be attached after the skin is riveted everywhere else to facilitate access to the middle rib flanges. Oh no! But, turns out, it isn't that big of a deal as I can easily access the rivets on the middle rib even with the rear spar attached. In fact, I wonder why the plans took a more cautious route, especially considering the "fun" time with all of the restricted access when riveting the bottom skins to the wings.
Finally, the rivets attaching the bottom ribs to the front spar are very, very difficult to set (if pop rivets were needed anywhere, this would be the place). It is possible to get a squeezer in on the rivets, but it requires deflecting the front rib upwards, which separates its flange from the spar. So I went ahead and bucked the two lateral rivets to make sure the flange was locked down and flush on the spar. I used my tungsten bucking bar, well taped, with my double offset rivet set. Then I squeezed the middle rivet, as bending the rib to provide squeezer access would no longer deform the flange.
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