W5HFS James Y. 'Jim' Bryce Austin, TX QCWA # 13498 Chapter 67

First Call: WN5HFS issued in 1954

The following photos show how my Tennadyne T-6 is mounted on a quadrapod. This is a simple means of placing a moderate sized beam on the typical roof. It is important to use the 2 x 8 boards on both the roof and inside the attic. These are then drawn firmly against the roof shingles and decking outside and the roof beams inside the attic by large all thread bolts distributing the load across four strong structural elements. Use decking screews to hold the 2 x 8s inside the attic in place for the final tensioning of the all thread bolts; these decking screws are simply to hold for placement and do not have adequate strength to substitute in any way for the all thread bolts. Use self locking nuts with rubber insulating washers outside and large washers and regular nuts inside for the final tensioning. Do not simply lag bolt the quadrapod to the roof decking and/or roof beams; such an approach has nowhere near the strength to do the job. The method illustrated distributes the load across much of the structure for a much more secure installation. Use roofing tar and flashing on the high sides of the 2 x 8s on the roof to prevent leaks. Use treated lumber outside and paint it to protect against weathering. Prior to affixing the 2 x 8s on the roof drill and mount the quadrapod using bolts and self locking nuts with the nuts on top. Notice that you can undo the nuts on the legs on one side of the roof and simply tilt the quadrabod with the beam over to the other side for ease of installation and repair. This type of work should only be done by someone well-experienced in framing capentery and in any case is not appropriate for larger antenna installations. The T-6 has a 12 foot boom and weighs about 47 pounds. Note there four non-metalic guys. These are a recommended precaution and should not be required for security of the installation. They are added as additional protection in the event of significant wind gusts. Be sure to fill their eyescrew anchors with roofing tar.

May 04, 2019