Lessons at Terminal Velocity

The joy of failure is that I am forced to learn from my mistakes. It feels joyless now, but really it frees me from the burden of choosing to learn. Either I learn and improve, or I will no longer be burdened with finding joy.

Work began this weekend to implement a portable 40′ tower mast so I can raise inverted-V and vertical antenna elements out in the field with no other support structures around. I’ve seen it before, and I know it’s a viable option. I’m using army surplus camo netting poles (they come in fiberglass and aluminum), and some modular brackets that I picked up in previous hamfests.

With some measurements of overall mast height, 37-ish feet, and the anchors which are 30 feet out (roughly 80% of mast height), our buddy Pythagoras tells me the guy rope length should be 48-ish feet. So today I measured and cut 3 guy ropes, and marked their length by the foot, with orange safety ribbons every 5 feet. Attached them to rings and everything.

3 ropes from RGB D-rings attach to the modular brackets on top of mast. Pulley to the upper left. Moments before first raising.

But something was wrong with my measurements and math somewhere. The ropes had too much slack, so on the four attempts to raise the mast, I could not get them tight enough, even after shortening them by a foot each time.

Mast on ground, ready for first raising. Root pedestal at far end, near table.

On the 3rd attempt, the root of the mast came loose from its tent peg, the bottom bounced up, and I couldn’t get my right hand out from under the mast before it jammed into my thumb. Thankfully I had gloves and a hard hat, but it just wasn’t enough.

Crack in fiberglass top section, formed after 3rd drop.

Unfortunately, I destroyed a mast section on one of those drops. You don’t realize just how heavy 60 pounds of mast material is until it’s 40 feet up and falling to the earth at increasing speed. Crack.

And when you get 10 sections of it in the air, you realize just how wobbly and unwieldy it is, and just how dangerous the whole exercise is.

End of day, end of lesson.

After the fourth lift with a replacement section, I gave it up. Live to raise it another day.

I have some thinking and physical recovery to do. I need to build a pivot base to anchor the mast. I need to recalculate the guy rope length with all the brackets, rings, and rope stretch factor. I need to find another rope tensioner solution — these Mastrant-brand friction claws are sketchy and I’m not trusting them any further for my guy ropes. I need to either use a shorter mast, or plan and cut some guy ropes for halfway up the mast for stability.

And for the love of Marconi, I’m not doing this again without a helper. It was stupid doing this alone in the field, with nobody to hoist ropes or call safety.

Hard lessons. Back to the drawing board.

Published by Shawn

He's just this guy, you know?