Thursday, December 8, 2016

Military and General Portable Mast Information, Part 1

This is the first part of the mast pages from my web site.
I need to do them in in parts because full pages overload Blogger.  Formatting is not exactly the same, but better than autoformatting.  Even though I paid for an independent site they even have my URL screwed up with the changes they made in November or so.
This cannot be emphasized enough. It is very tragic when the news hits that ham radio operators were killed while erecting a mast or antenna. Several years ago I think some Boy Scouts were killed and some severely injured when erecting a mast too close to power lines. The first rule of safety when erecting any tower, mast, or antenna --LOOK UP! The second rule is STAY AT LEAST TWICE THE DISTANCE AWAY FROM OVERHEAD CONDUCTORS AS THE HEIGHT OF THE MAST OR TOWER. As in, if your mast is 50 feet tall stay at least 100 feet away from the closest overhead conductor.
I have at least 5 news articles from 2009, where one or more of the same family were killed by not heeding basic mast/antenna/tower construction safety practices when installing an antenna or mast.

Now the leagaleze. This information is provided as a method of doing things; what I did. It is not the only way. I am not telling you how to do it. Those of you who take on any project or idea from this website do it by your own action and responsibility. I am not responsible for what you do. YOU are. I have witnessed operators erecting these and similar masts in all kinds of unsafe ways. Notes on this site are to assist in SAFE use of these masts, however I cannot be and will not be liable for your use of any of these masts or methods I have used or any property damage or injuries.
The masts and information on this page is for temporary deployment of masts and antennae for Field Day or portable operations, NOT permanent installation.
One of the popular items on various news groups and in several web discussions is the use of Military Surplus LCSS aluminum (1080-00-108-1173) and/or fiberglass (1080-01-179-6025) mast sections to support an antenna. This can be done safely for temporary installation for field operation. Our club does it for Field Day. I have seen several Ham Radio Clubs use these and do it successfully although not all do it as safely as it can be done. Remember these were designed and deployed by the military for supporting camouflage netting over vehicles and encampments.

Let's start with the mast sections themselves. Tons of these have hit the surplus market over the years and Ebay is flooded with them most of the time. Beware of the fiberglass mast sections withoutfemale end reinforcement rings. There are also some with plastic rings. The plastic rings break. They do not work. These no ring and plastic ring sections can split.
The fiberglass masts without the ring are fine for N.V.I.S. sets as the mast is only installed to a height of 15 to 16 feet. Four sections high is plenty of N.V.I.S.
These poles are part of the LCSS camouflage support system they were not issued by the military for antenna masts. There are at least 3 versions of the plastic poles -- fiberglass, and 2 versions of the aluminum. The government calls the fiberglass poles plastic. These poles come in 2 wall thicknesses and 3 styles of female ends. some of the female ends have a nice fiberglass reinforcing ring, some have a worthless plastic ring, others have no ring. The plastic and no ring may be modified to be stronger as noted below. Some fellows even reinforce the male end that mates with the coupler.
The aluminum come in 2 styles, plain and ribbed walls. The plain are heavier and in my thoughts stronger than the ribbed. The plain are thicker walls than the ribbed.
They all come in woodland (green), desert (tan), or snow (white). The government classifies the sets as radar scattering or radar transparent.
Female end rings, fiberglass masts.
One method I used to make the rings to reinforce the female ends when they do not have rings is to get the required quantity of 1-1/4" Schedule 80 PVC couplings and bore them to fit the outer diameter of the mast. This requires a lathe. Bore them to a slightly loose press fit.
To attach them I used Devcon 2500 epoxy from Wal-Mart #S-31 313-15. It is rated for 2500 pound tensile strength. Be sure the epoxy can be used on fiberglass. In review of mast sets in use for the past 3 years I do not recommend using and/or modifying any of the masts without the end ferrules as manufactured. The epoxy comes loose! There is a hot melt that seems to work and Liquid Nails for projects seems to work, but the ferrule-less masts should be scrapped. I do not trust them. The walls are thin and any kind of end reinforcement may not be reliable since these masts also split at the male pin end. (The no ring masts work for N.V.I.S. since they only get stacked to a maximum of 4 sections. There is not as much stress on the joints for N.V.I.S. as there is if the mast is extended to 12 sections.)
The ones without rings and the ones with plastic rings are light weight and have a bit thinner wall. Adding reinforcement collars will strengthen the end and help prevent splitting to a degree. The ones with the female end reinforcement rings are a bit heavier since they have thicker sidewalls. I only use the ones with end rings.
One other note on purchasing fiberglass masts. How are / were they stored. Many times these masts are stored outside in direct sunlight. If they are in the carrying case or other storage device they will get hot, but not generally deteriorate. If they are stored in direct sun and not protected they will deteriorate. Sunlight eventually weakens fiberglass. If the masts are dull and fibers are exposed chances are these sections spent too much time unprotected in direct sun and may be weakened.
Many, if not all, of the hardware items mentioned here can be purchased from McMaster-Carr if you cannot find it at your local hardware store or surplus dealer.

Above is a photo of a fiberglass pole with an original reinforcement ring at the female end. This is the heaviest of the fiberglass poles.
Here is a list of the of the variations of these support poles from what I found on the internet and in a TM:
1080-00-108-1173 MIL-C-52765 81349 Support System, Woodland/Desert, Type I
1080-00-179-6025 Support System, Woodland/Desert, Type II
1080-00-556-4954 MIL-C-52765 81349 Support System, Snow, Type I
1080-01-179-6024 MIL-C-52765 81349 Support System, Snow, Type II
1080-00-108-1595 MILC52765 81349 Adapter Assembly, Woodland/Desert
1080-00-108-1646 MILC52765 81349 Carrying Case, Woodland/Desert
1080-00-563-6342 MILC52765 81349 Pole, Support, Aluminum, Woodland/Desert
1080-01-165-9027 MILC52765 81349 Pole, Support, Plastic, Woodland/Desert

1080-00-108-1545 MILC52765 81349 Spreader, Batten, Woodland/Desert
1080-00-108-1654 MILP501 TYPE I 81349 Stake, Steel, Woodland/Desert
1080-01-081-1022 MILC52765 81349 Adapter Assembly, Snow
1080-01-073-3195 MILC52765 81349 Carrying Case, Snow
1080-01-075-5113 MILC52765 81349 Pole, Support, Aluminum, Snow
1080-01-165-9026 MILC52765 81349 Pole, Support, Plastic, Snow

1080-01-073-3196 MILC52765 81349 Spreader, Batten, Snow
1080-01-075-4017 MILP501 TYPE II 81349 Stake, Steel, Snow
1080-00-571-5015 13226E0969 97403 Lanyard with Pins
I have been unable to locate the FSN or anything else for the ribbed aluminum poles. According to TM-5-1080-200-10 the -1173 system contains aluminum poles and -6025 systems are the plastic poles.

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