I spent much time agonising over how to get my hexbeam in the air! Over a period of 3 weeks I got quotes for a variety of masts from NZ$600 to 2400 British pounds!!
My rotator weighs 9.9 lbs, the book said so. Most estimates of hexbeams were "less than 20Lbs". My Hexbeam total including the fixed mast part, the antenna complete, and the rotator is well under 20 lbs measured with a spring balance. Coax and cable weight will have to be added. The biggest saving is in the fibreglass spreaders, and it is only a 3 band ant'. People ask how the mast works - but it isn't rocket science. The best innovation is perhaps that hole in the ground. (If only it was 50 foot deep???)
Brief explanation, but study the picture....click to enlarge.
The timber post is concreted into the ground with the 75mm hollow tube close to it. The 'black' steel pipe support between B and C is welded to a U section which straddles the 4x4 H5 treated timber. It is made exactly vertical and bolted through the timber. The 2" ali' mast sections will easily slide through it. (The gloves are ready on the little tool shelf).
At point A the 75mm tube in the ground is about a half meter deep. Point B is about 1.3 mtrs above ground level. A 1.6 mtr length of 2 inch(50.8mm) pipe can be place in the hole at an angle and then made vertical to line up with the pipe above .
The mast at point C can be lifted up and down within the (black) steel collar as required to allow 1.6 mtr pipe sections to be added or removed for lifting or lowering respectively. Lifting about 20 lbs of pole and antenna is not difficult provided there are no side forces on the array. In other words a calm day is best, in fact essential if going the full height.
Above shows the opposite ends of 1.6 mtr mast sections which telescope together.
Beware of the dangers of structures like this. Keep clear of neighbours fencelines, and especially
POWER LINES.
YOU are responsible for what you build, not me.
Observations, and care needed.
1. If lifting at point C and you inadvertantly lift the mast completely out of the "black" collar, you could be on your own holding a very tall top heavy mast - you will likely need to let it fall!! Clearly any guy ropes need to be very slack to lift the mast.
2. In concert with 1 above - the join at C can come apart when you lift. Best have a bright helper who knows the drill.
3. Use gloves. If the mast is allowed to slide down into the collar with you holding the weight of it your skin can get dragged into the collar! DON'T do that. When the bottom end of the mast clears point A it can be grabbed and lifted from there.
3. The hole at A is about 3 foot deep. It is a good idea to place a solid pad at the bottom of it. Also use the same 1.6mtr mast section at the bottom - one with the hole blocked up. The downward pressure will not sink the mast into the ground so easily.
You could put a locking collar at point C of course. I have used two ss jubilee clips buffered by a piece of the plastic pipe to add both thickness and protection around the mast at point C. This takes the weight of the array and seems better than leaving the weight at the bottom of the hole in the earth. It is lifted about 2 inches only but it will be realised that another 5 or 6 feet of height could be arranged! I would not trust the clips alone.
4. The hole at A must be vertical but also wide enough to allow the 1.6 mtr mast sections to be angled into the hole. It must not foul the collar at point B.
5. If you build something like this you are advised to raise and lower in very calm nil wind weather conditions and whilst you might manage single handed - far better to have a helper.
Points of Merit
1. Relatively low cost.
2. Only two sizes of tube are required.
The mast is 50.8mm T8 aluminium tube 1.42mm thick. The joiners are one size smaller in dia and a sliding fit.
3. The "working height" when retracted or whilst assembling allows easy access to the essentially horizontal hexbeam. The beam can be happily rotated since it just clears a 6 foot head height. This is very useful it clears a 6ft step ladder needed to reach the center pole.
4. In theory and with sufficient guy wires, considerably more height could be achieved.....but I am scared of heights!!
5. I am very grateful for the friendly help and great service from Jim Lowry, factory manager at Ullrich Aluminium Co, Wiri Stn Rd.
6. The tubing lengths of 1.6 mtrs are derived from cutting the available 5 mtr lengths into three. Then they fit in the average car. I bought one and a half lengths, 5mtrs plus 2.5 mtrs and also a 2.5 mtr length of the smaller size. I could lift my antenna to about 30 feet with that material.
There was a short Youtube clip showing how it works. For some reason it disappeared!!
After a visit to hospital I was advised to do no lifting for a month or two.
This winch solves the problem. Although the array is light weight this still makes it much easier and allows one man operation on a calm day.
I have used flexible wire rope, it is galvanised and can hold about 1000 Lbs. The total weight to lift is less than 30 lbs.
(Click for big pic)