Another tower project, 40m Yagi

[Rob_Walker]

I'm trying to take advantage of some of my down time to get a new tower up with a 2-element Mosley 40m beam on top.  The beam has been in a box at my front door for a few years now and I have had the tower sections in the back of my yard for almost the same amount of time.

The tower is a light duty Wade but the boom for the Yagi is 15' and the elements are 46'  long.  I am anchoring the tower with guy lines at the 30' and 40' mark.  I needed some headroom for the guy lines so the support for the lines protrude 5' out of the ground.  I used 1.7" Schedule 40 pipe with 1/4" walls and sank this 5' into the ground with lots of contrete.  Inside the 1.7" pipe is another 1-1/2" Schedule 40 pipe with 1/4" walls so the supports are very rigid.




Even though the tower is not free standing, I still used just over 1 cu. yd. of concrete and 8" of stone for drainage.  The concrete had to be hand-bombed from the street to the back of my yard.




This afternoon I started fabricating two torque arms out of 2" x 2" angle iron.  My guy lines will attach at the torque arms and prevent the tower from twisting in on itself.  The upper guy wires will be 40' which would require me to break the guy lines up so they don't couple with the antenna.  



I found I could make neat and precise work of my angle iron cuts using a 10" Dewalt mitre saw, an 80 tooth metal cutting blade and a cheap speed controller to keep the saw around 1800 rpm.

[VE3WI Dave]

Very impressive work Rob!

Is that steel angle you're using?  I've cut a lot of aluminum stock with a metal cutting blade on my table saw, never tried steel as the blade is labelled non ferrous only.  I've cut steel with an abrasive cutoff disc on a Skillsaw - usually end up setting something on fire :-)   What blade are you using?

If you need an extra pair of hands any time, my calendar is mostly free these days.

73
Dave, VE3WI

[Rob_Walker]

Hi Dave, thanks for the offer.  I'm using an Irwin 80-tooth blade that's good for mild, thin steel.

https://www.amazon.ca/Irwin-Industrial-T...B0030XMFIO

[Rob_Walker]

Is that steel angle you're using?  

I missed part of your message Dave.  Yes, it's steel angle iron.  I chose steel because I don't have the equipment for welding aluminum.

[VE3WI Dave]

Thanks Rob.  Very nice work.  Maybe host a GBARC meeting so we can all see your antenna farm
73
Dave, VE3WI

[VA3KOT John]

Great job Rob. So, you can weld steel eh? That could make you a very useful chap! I am sure most of us have neither the skill nor the equipment for welding.