Dome build: Fresh start up in the crow's nest.

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I give up! No, not completely. I just cannot find a way to complete the top tier of the dome. I have wasted enough time on it now. Weeks, in fact, all told. I shall just have to build the top section of the dome in place. Up there on its supporting rollers. 

Nothing else makes sense at this late stage. I need to glue short sections of ribs together and to the lower ribs sections with deliberately lapped joints for strength. Then the vertical struts have to go on.

 I cannot fix anything to the observation slit ribs or top crossbar until they are all joined to each other. So I can't fix the gores together either. It's a complete mess of loose bits. Once glued they will be fine. Right now the gores sag or are propped up against the slit frame with no secure location.

I shall leave all the [numbered] panels off to allow the horizontal struts to act as a ladder. This will allow me to climb freely on the dome surface itself. It has proven easily stiff and strong enough to cope even when not even glued together. Thanks to the spherical geometry the gores [segments] lock tighter into each other by friction alone. Even the spring clamps were easily strong enough to allow free climbing on the structure.

The gores will be much easier to handle without the frame being closed off by the panels during lifting and assembly. Everything is marked and numbered and my frequent rebuilds have proven it is very easy to assemble. Naked gore frames will also allow my to tie off my smaller ladders for security when climbing up off the outside veranda. I can also work off a ladder inside the dome of course.

Accessing the exterior is easy through the wide, open slit. I have a climbing harness, carabiners and plenty of rope for security and never take silly risks. There is a lot of gluing and sealing ahead but it is not difficult to do. Particularly if I work downwards.

The morning was spent on mass production of fourteen [and two half] gores gluing the horizontal struts to the ribs. I worked under the tent style awning to shelter from the hot sun. Four screws per half rib x 28 had to be backed off enough to squirt some adhesive into the gap with the mastic/caulk gun.

These images show the end of a busy Sunday preparing for assembly up on the rollers. It was a real struggle to get the board-reinforced ring up the inclined plane of two ladders. There is always a point where the crossed battens simply won't go over the mounting. While the ring is still hanging out over the ladders. Finally the ring is back in place on the rollers and spins freely.

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