K1TO called me in to help w/the K4TD OptiBeam 80M Yagi problems.
The boom was showing signs of coming apart. Dan had installed some stop-gap fixes, but the decision was made to try & get the beam down, on to the ground. Then repair it, & re-install it atop a new, dedicated 80M tower, to be 200 feet of 45G. So…I headed to Alabama.
The boom was in worse shape than the emailed photos demonstrated. It had continued to separate. I suggested we use a crane & remove the beam, but… for a variety of reasons, the decision was made to try removing it the old fashioned way—-by tramming it down.
Despite serious & hard-fought efforts to get a splice attached (a simple crutch surrounding the square boom, made from two 6ft lengths of aluminum channel), along with a newly-made & installed self-contained truss system, when I unhooked the existing truss system from the tower siderail, the boom nearly came apart. It took all my strength to hold the damn thing up there, while I attached a sling to the Z-bracing. Then, for safety, I added the little Mini-Mule comealong, as well as attaching the new truss line. It’s still bent over & looks pretty precarious.
After de-rigging everything & climbing down, I convinced Rick we could get a crane in there, take the elements off the boom from a man-basket one at a time, & then take down the damaged boom. That’s the order of the day for today, Monday—getting the crane guy on site & ensuring we can get in close enough & high enough to reach the boom. (The antenna is at 187ft or so…)
While I wish I’d stamped my feet, cried, swore or otherwise raised a serious temper tantrum fuss, so we’d have gotten the crane going first, it’s understandable. Folks are reluctant if/when they’ve never worked with one, the added expense, the sheer size & scope, et cetera, all work to frighten them away from the idea. In the meantime, the busted boom sways gently to ‘n fro, & we’re all hoping no serious winds come up until the damaged beam can come down.
This is the third OptiBeam 80M Yagi to suffer similar mishap. That’s not a condemnation, merely a simple declarative statement. I remain unconvinced, however, that their four-section boom design (used on 40M Yagis on up) is a viable approach to big Yagi construction. While climbing up, the section splice bolts on the 40M beam were also found to be loose, for example. I much prefer round booms, with telescoping tubing inserted inside, to this threaded-stud insert system. With the telescoped tubing style construction, even should the through bolts fall out, the tubing is still supporting the splice. With these studs, once the bolts come loose (let alone fall out, as four of these had done!), the integrity of the splice is gone.
In the meantime, I’m falling further behind on other jobs. That won’t be helped now that recently-hired helper Shaun moves on to a permanent, “real job,” et cetera. Ahhhh, the life of the itinerant tower climber…~!
The crane company is coming today; we’ll know more shortly….
Heading back to Alabama Tuesday morning; crane arrives Wednesday AM.