Storm Damage, 2/6/2020

I had a little storm damage to the tower mounted antennas on 2/6/2020, though only a small amount. My tower is 105' tall, and the yagi antennas are mounted on top of that. The lowest antenna is the 6el Force-12 HF yagi, the middle yagi is the Cushcraft a50-5S 5el 6 meter yagi, and the top yagi is a Cushcraft 13B2 2m SSB yagi. 

We have had a weird winter...warm and wet. This is normally the time of year where we have temps in the low teens and the largest snowfalls. This year, we've barely run the home heating system, with lots of days in the 50's, 60's, and even 70's...and lots of rain. On this day, the temps started off in the 70's, fell about 20 degrees, and tremendous winds blew through. Rain storms were reported at moving over 100 mph (!!) by the local weather station, and there was lots of wind damage. We had loads of tree limbs down, but the damage in the photo below is the only antenna damage I had. The Force-12 at 105' was twisted on the vertical mast, the 6m 5 element yagi had a little damage to the reflector, and the tower mounted dipoles for 80 & 160 had a limb hanging on them. That's all! I'll take that any day, compared to the storm damage in 2016 that took the tower down :-)

Dave WB4IUY
www.WB4IUY.net

6M Yagi Rebuild Finished!

Finally, after 2 years, I have completed the rebuild of my Cushcraft 6M 5 element yagi. All repairs are made (see previous blog posts), it has been tuned, and broken back down to haul up the tower for installation... 

 Here's a pic with the antenna mounted on a temporary test tower section in the back yard for assembly and tuneup. 

Here she is, broken down and ready for transport up the primary tower. I'll move on and get the next antenna repaired and bolted on the test tower. It's nice to finally get these antennas brought back to life from the scrap heap. The cost of this (re)build from the scrap pile was only about $10!

Dave WB4IUY
http://www.WB4IUY.net

6M Yagi Rebuild, 3rd evening...

I got a little more done today, almost ready to attach the elements to the boom and tune it. I mounted the boom on the test tower section, adjusted the element lengths per the manual, painted the repairs/splices in the elements, drilled the repaired elements for the boom mounts, and capped off the ends of the elements to keep water / insects out. Here's a few pics...

 The repaired boom is now attached to a short section of tower in the back yard for testing....

 Drilling the repaired element centers for assembly onto the boom mounts...

 Lengths of the elements are now adjusted per the mfg specs...

 Element splices / repairs now painted...

The ends of the elements are now capped off to keep insects and water out...

Dave WB4IUY
http://www.WB4IUY.net

6M Yagi Rebuild, 2nd Evening...

I got in from work a little before dark today, and decided to work on the 6M yagi project a bit more. I spliced the broken sections with 1/2" type M hard copper from the hardware store... This stuff is stronger than the aluminum it's repairing, the short sections won't add much weight to the yagi, and it's CHEAP :-)  I've repaired antennas like this that held up 20+ years and are still working.

The center sections of the elements were supposed to be 48" long, each. They were mostly broken right around the boom attachment point. I cut out the crimped sections, cut the copper long enough to extend into the aluminum 3" on each end, and restored the center sections to 48" long. I drilled the tubing and secured it with 1/8" pop rivets, then used the low temp flux core aluminum brazing rod to solder the parts together securely for a continued good electrical connection. The brazing rod comes from Home Depot, and is the type that melts about 700 degrees F... This allows the use of a small torch to handle the job. 

After the elements were repaired, I did a quick mock up in the yard... see the last pic. Day 3 should allow me to get the boom mounted on my test tower, and get it marked up for test assembly. Here's a few pics...

Installing the splice sections, drilling, and pop riveting.  

Checking for straightness, after returning from the redneck tubing straightener, described in my previous blog...

 

Cutting out the damaged sections...

Checking more elements for straightness...

The matching section is in pretty foul condition...

 I soldered the copper splices into the aluminum elements for continued good electrical contact...

Propane Torch and low temp aluminum flux core rods...

Another element after soldering the copper splice to the aluminum element. 

A quick mock up in the back yard to get a feel for the element layout. It's beginning to look like a yagi, again :-)

Dave WB4IUY
http://www.WB4IUY.net

Beginning the repairs on my 6 Meter Yagi...

This is a Cushcraft 5 element 6 meter yagi, another fatality of my tower crash back in April 2016. I'm getting things repaired and reinstalled, slowly but surely. We joked around on the air and called all of my Cushcraft antennas... Crushcraft, since they were all crushed in the tower failure. 

Today I pulled all of the parts of the 6m yagi from the antenna wreckage pile, and began disassembling everything. Some stuff was bent, so I straightened those items and put them to the side. One of the elements (1st director) was actually straight... I couldn't believe it, considering the condition of everything else. Here are a few pics of the first evening's work... 

 This is pile, after it was pulled from the tree and tower wreckage about 2 years ago...

I laid it out in the back yard to figure out the component layout prior to complete disassembly...

 Broken stuff...

 ...more broken stuff...

..and more broken stuff.

The driven element is in foul condition...

The boom mount and element supports were twisted and/or broken along the length of the boom...

 

I began work on the boom...it was bent up pretty good...

I employed my red neck tubing straightener that I've used before... a pair of twin trees in the woods behind my house. Trees work pretty good for this, their surface is soft and doesn't tend to wrinkle or crimp the tubing at the points of contact while straightening it. I first straightened a motorcycle crash bar in those trees about 15 years ago...

Here's the boom...nice and straight!

The 1st director was warped up a bit, so off to the red neck tubing straightener it goes...

...and it comes out nice and straight! Next, I have to pick up a short piece of tubing to make splices for the broken elements. More on that in the next blog update...

Dave WB4IUY
http://www.WB4IUY.net