Assembling the Tower Sections
Below is the beginning of the assembly of the first section. I placed the legs on some of the same timbers that came with the shipment. (There was a small fortune in lumber that came with the tower!) They came in very handy. Since the legs are bowed due to the welding of the cross-brace anchor plates and the apparent lack of sufficient straightening, it worked out best to start by placing the diagonal braces on the ends first. (Called "lacing it up" in tower parlance I've learned.) Once the two ends were laced up, I used the forklift to suspend the upper leg and then laced up the ends of that too. Once the ends are laced up on all three sides, I used a ratchet tie strap wrapped around the middle of the span to pull it in because of the bow in the legs. It really wasn't that tough. A little pry here, a pull there, loosen the strap, tighten the strap etc., and the bolt holes lined up one by one.
The first section complete. This is actually the top section which in the case of my tower is 12' long. The rest are 20' long. I figured I'd start with the easiest one and work my way down to the more difficult, and larger sections.
Top section again. The finished foundation can be seen in the left background.
This is the next day, raining again, after completing the first four sections. All braces are just finger tightened at this point. Nothing is wrenched in place until the end. It has to be free to move so it can be lined up when it comes time to bolt the sections together on top of one another. This is obviously not a close tolerance industry! More like dealing with I-beams and rivets! You'll want a good 4' pry bar handy and a helper would work too. I managed to assemble the first 4 sections (half of the total of 8) by myself, no helper, in one day. And I actually got a late start. So at this point, other than the constant rain we have here in northern California this time of year, it's actually starting to go faster than I expected. A welcome change.
Another angle. The closest section on the right is the top 12' section I did first. You can see the flange plates as you look toward the background. That piece on the right is three sections placed end to end, but not bolted together. If you look closely you can see the flange plates where they will be bolted together. The section on the left is the forth from the top; the first section where the legs aren't parallel. The tower begins tapering out at that point to reach the 14' 8 3/8" span at the base.
A shot of the first flange joint down from the top. All these parts are hot dip galvanized and in some places it is VERY thick, even to the point of it having solidified as it was running off the parts. In many cases the bolt holes were full of zinc to such a degree that I had to use a round file to open them up. Be careful not to cut too far though, it's best not to expose any of the steel if possible. The zinc is thick enough though, that you can easily open the hole up without getting anywhere near the steel. There is somewhere in the order of 800 pounds of zinc galvanizing on all these sections.
The pics below show the assembly of the bottom tower section right on the foundation.
All sections of the 150' Rohn SSV.
These few pics below were shot late in the afternoon January 5th, 2003, with little light, but I wanted to get a few shots of the base plates at this stage.
Some "Step Bolt" detail.
The bottom section assembled on the pad.