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G8MNY  > TECH     12.06.19 11:45l 75 Lines 3210 Bytes #4 (0) @ WW
BID : 8035_GB7CIP
Subj: Vehicle Gutter /P Mast Support
Sent: 190612/0933Z @:GB7CIP.#32.GBR.EURO #:8035 [Caterham Surrey GBR] $:8035_GB

By G8MNY                                             (Updated Apr 05)
(8 Bit ASCII graphics use code page 437 or 850, Terminal Font)

Here is a mast support system for the side of a car or van with a gutter.
(Other roof supports are possible for example an extension from a ladder rack,
or a metal sheet shut in door/window to support the mast, the higher the safer!

         ├┤ Walk up or
         ││ Extendible
         ││ Mast System
 X frame ││
 Bracket ├┤
  .---.\_││  Windup Extendable mast
 │ Van │ ││  system is in another bul.
 │_____│ ││
  U   U  ││

                     GUTTER "X" FRAME SUPPORT

CLAMP ARRANGEMENT                       PLAN VIEW
Self Tap     Threaded                            Amalgamated tape covered
  Screw v    | rod |         Thick      GUTTER    ======================
___   ,====================== 8mm         ^  Clamp\\\    8mm tube    ///Clamp
VAN\  `====================== tube        |          \\            //
Roof`\ (_)│  │     │__..--''            Van Side       \\        //
Gutter`---'__│.--''U   Thick           Clearance         \\ .. //  3 Good Self
       │ '' /U\        plate              |               .\\//.   Taps @ Tube
   Side│   Clamping                       |              . //\\ .     Joints
           Wing Nut                       V              // -- \\
                                                          . -- .     . = Bungee

If the Car or Van an has a conventional gutter on it this method gives a sturdy
mast support at the gutter height, in my case at 2M.

Construction: You use 3 pieces of thick ally tube to make a large triangle
about 40cms a side (or as required to clear your car & curved roof etc).
The 2 longer pieces cross over to form the pole support X. Drill holes & put 2
well fitting self taps into the upper side of the shorter tube, then 1 at the X
point. Now at cut some steel plate (2-3mm thick) to make the under gutter
clamps, 6cm long, with the car end angled to match. Drill holes for 2 thin long
thread rods or bolts each one left loose as a locating pin & the other with a
wing nut to clamp up plates to the gutter. When the construction is done tape
the gutter tube up to be snug fit & the clamp ends so as not to scratch the
paint work.

Pop the pole vertical, attach to X bracket (bungee). Use the bungee tension to
stop the mast for turning! Keep the bottom position on the ground to keep

Depending on conditions bottom can be left on the ground or a bearing plate
pegged in. Drive over bottom bearings/supports seem a good idea, but U need to
be able to reposition it to make the mast vertical.

It is generally wise to have cables well secured, either just to the top of an
extending mast or all the way down on a walk-up one.

In public areas I always guy the mast with 4 guy strings for safety as well!

Also used with it is a 12V rotator that the mast sits on. It is a low torque
easily stalled rotator so of anything fouls up it does no damage!

Why Don't U send an interesting bul?

73 de John G8MNY @ GB7CIP

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