[TowerTalk] Climbing mast

[Jim Thomson]

Date: Wed, 2 Dec 2015 11:11:00 -0500
From: "Ed Sawyer" <sawyered at earthlink.net>
To: <towertalk at contesting.com>
Subject: Re: [TowerTalk] Climbing mast

Its serious ?pucker factor? doing a 10 ft mast climb at 80+ feet.

 

Personally, I have found that I can pull the rotor and drop the mast down
with a ?come a long? to a serviceable height of 5 ft (allowing me to at
least stand on top of the tower) in not much more time than build the steps
up as they go.  Takes about 2 hours to have my top antenna where I can get
to it from the top of the tower and about 2 ? hours to have it all the way
down to sitting on the tower.

 

Ed  N1UR

##  Your method works.  In my case we are talking about a 140 lb mast,
and a 80m rotary dipole at top, 20m yagi in the middle and a 3 el 40m yagi 
at the bottom. Plus the  K7NV  50 lb  prop  pitch, that is embedded  6 feet
inside the top section of a HDX-689  crank up tower. 
With this setup, it’s a bitch to  remove the rotor..and lower the mast.  
The mast steps are installed once...and stay there
permanently.   I also use the same  DX eng clamps  for each  yagi.   2 used
on the 80 + 20m arrays..and  3 used on the 40m yagi.   That way I can
stand on the plates as I climb the mast.  

##  I duplicated the F12   double plate, boom to mast setup, except that 
I used  .375 inch thick plates,  6061-T6, for both H and V plates.   Dx  eng
heavy duty U bolts and solid saddles used on the H plate..and the DX eng
super mast clamps on the V plate.  On the 40m V plate, 3 mast clamps used,
2 at the top, and 1 at the bottom.   I made the H plate on the 40m wider, aprx
17 inches, so that I could install 3 SS  u-bolts and solid saddles per side. 

##  as far as pucker power, its really no big deal.   I use 2 lanyards on the mast.
One around the mast  as Im climbing up. Once  into position, each lanyard
is wrapped tightly around the mast several times to take up all the lanyard slack. 

##  standing on a 2 x  2 inch x 14-15 inch wide  AL  angle..esp with the non skid stuff
on both the V and H surfaces  of the angle AL..which is  .25 inch thick, is no big deal.
Being 2 inch wide, you can easily stand on it for a long time . 

##  I used a 2 inch  x .375 inch thick mast, cuz the tower was setup for a 2 inch mast.
My 1st choice for a mast would be a 3 inch OD mast...with a .25 inch wall thickness. 
It weighs the same as a 2 inch od  x .375 inch thick mast.... but is one helluva lot stronger.
Having said that, a 2   x  .375 wall  4130 chromolly mast isnt going anywhere. 

##  IF mast steps are used,  use lots of em, like every  12-15 inches. 

Jim   VE7RF