Guy Posts FAQ Assembled by Fred Hopengarten K1VR As of April 2, 2001 I just installed elevated guys this last year with my 60 foot tower here in Kansas. Using 6 inch steel pipe which has a wall thickness of slightly less that 1/4 inch (almost schedule 80), I buried three feet in the ground with 7 feet sticking up out the ground. (I am 6'4" and do not want to hit my head ever again on the damn guys!) I dug a SQUARE hole and filled the hole with concrete six inches from the top of the hole. (If I ever move, I can cut the pipe off below ground...put dirt over the holes...grow grass...and no one knows the difference.) I used ship paint to paint the pipes before pouring concrete to cut down on rust and such. I had "ears" welded onto the top of the posts where 3/4" hardened bolts go to the turn-buckles. It took three guys to move these behemoths to the hole and stand them upright. I them poured concrete to the top of the posts filling them entirely. The concrete was cured for three weeks before any stress was placed on the guy points. The holes are square to keep the turning momentum at a minimum. My brother who is a PE looked at the installation and said: "The damn house will go in the tornado, but the tower will still me there." (Would you trust his engineering license?) Guy tension is snug, but not tight since I don't want to "compress" the tower downward into the ground. The idea is to stop the tower from moving side ways violently at the top and middle in wind. There is some play in the guys, so there is not all that much pressure against the guy posts. Since I have installed these guy points (which were my first) we have had at least 10 days of very heavy wind here...which blew the damn beam off the tower!!!! Yes, the beam was badly damaged, but the tower stood the test. This year in Kansas we have had several wind gusts to 70 and 80 MPH in blowing rain and snow. We've had days where the wind blew constantly at 30 to 50 miles an hour. This went on for more than 24 hours at a time. I keep a close watch on the guys posts for ground movement and see none. Total cost: $100.00 (with concrete!) Guess I didn't go high enough with the tower. -- Lee Buller k0wa@southwind.net ===== Lots of interesting threads on this--everyone's situation unique! I have 110' Rohn 55 in a fairly tight location--two guy points only 53' from the tower. I needed to clear a garage and (obviously) move the effective base out as far as possible. The tower is guyed at 50 & 100' (the move to 55 from 45 enabled the elimination of the 3rd guy set which would have made side mount rotation in this tight setting impossible). Using the home (not farm) set up at W0AIH as a model, I used double wall 8" seamless pipe--13' long for the two short guy points. Holes were dug 5' deep, 3-1/2' square, and filled to 1 foot below ground which will allow torching off and filling. Ground is heavy with rocks. I painted, prior to planting, with best available anti rust paint after welding 1/2" bar on the top with 1/2" holes for Rohn jaw/jaw large turnbuckles and one extra hole for the tensioning come-along. The pipe is so strong that there was no need to do anything but make them straight and fill the top foot or so for water protection. They look great and have withstood 85 MPH winds with about 30 sq ft antennas/mast without a shudder. (20' chromolly mast at top--4' in, 16' out). The 13 footers weighed about 425# and were surely a trick to get straight and in the center of the holes, but it was worth it. My PE friend said I'm in good shape. John, K0IJL ===== I'm no engineer, but here's my experience with elevated guy posts. At old QTH in Bear, Del., I had 100 ft of Rohn 25, guyed at 33 ft, 66 ft and 100 ft or thereabouts. Two of my guy posts were 10-foot long, 3.5 inch galvanized steel pipe from local junk yard. The wall was at least 1/4 inch thick. Each was set 3 ft into a block of concrete that was about 2 ft by 2ft square by 3 to 4 ft deep into the ground. At the center of the hole, I dug down an additional two feet or so with a posthole digger, and in the center of that I drove in an 8-ft long welding rod (over an inch in diameter steel). The elevated post was placed over the welding ground rod and guyed temporarily to keep it vertical, then the hole and the pipe were filled with concrete. At the top of the elevated post two holes were drilled to accommodate a piece of 5/8-inch galvanized steel, threaded rod (pole hardware) perpendicular to the plane of the guy wires. These were inserted before the concrete filled the pipe. The turnbuckles for the guys slipped over the threaded rod (two on one side of the post and one on the other) and a nut made sure they didn't slip off. At the bottom of each post several holes were drilled and 12-inch long, 5/8 inch diam. galv. steel bolts or rebar was inserted to keep the post from twisting. The third post was a 4-inch diameter, 12-foot long non-galvanized piece of steel pipe from a neighbor's junk pile, installed similar to the other two above. They were in place for 10 years, and the tower never fell. The posts never budged (one of them took on added duties after the first couple of years as the guy point for a second tower, and later the same post was the guy point for a third tower). I shaped the concrete at the top of each post so it was convex -- bulging up a bit so rainwater wouldn't "pool" there. I never bothered to paint any of the posts -- not even the non-galvanized one, which had a heavy rust coating on it, though that might have been a good idea for a longer-term installation. I think the new owner (not a ham) used some dynamite to remove the posts. After these were installed, I read an article in CQ about elevated guy posts that used much less concrete -- perhaps 6 inches in diameter or so. So here at the new QTH, the blocks are not quite as big (only 12-18 inches diameter, and 4-5 feet deep) and I didn't bother with the 1-inch rods down to 8 ft deep. Now all of the posts are galvanized steel and 4-inches diameter, filled with concrete. On one post, where I had to get the lower guy a bit higher to clear potential vehicular truck traffic in the driveway, an additional 2.5 inch diameter steel pipe was inserted into the 4-inch pipe (the 4-inch pipe sticks up 7 feet above ground and the smaller pipe an additional 7 feet or) and also filled with concrete. The tower now is 120 feet of Rohn 45; house-bracketed at 28 feet, guyed at 60 feet and 100 feet. Nothing's budged in 5 years. The Rohn 25 held a 204BA and a 4-el 15m Wilson Yagi (17 ft boom). Catenaries for 80m and 40m wire arrays also tugged on one side of the tower at 70 feet and 80 feet or so. The Rohn 45 holds a 204BA (at 120 feet) a 3-el 10m Yagi at 108 ft (side mounted), and the Wilson 4-el. 15m Yagi at 100 feet, and a 20 ft boom at 90 ft that supports 80m 2-el wire Yagi and 40m 2-el delta loop. A 160m bent 1/2 wave sloper also hangs off the tower at 100 ft. Stacks to come on 20 and 15m. -- Jon AA1K jon.zaimes@dol.net At 11:27 4/22/96 -0500, Charlie Ocker wrote: >I am in planning stage of next phase of tower project. It will be 73' of 45g, >guyed in 2 places per Rohn specs. I'd like to bring guywires to elevated posts. >Thinking 3 or 4 feet above ground. I have access to some fairly good size >steel posts (4 to 5 inches diameter, hefty wall) but do not know specs of the material, as it is surplus. > >Would appreciate any hints, kinks, pros/cons, etc. Will make a summary available for those interested. -- Charlie KD5PJ/9 ocker@chasind.com >Date: Mon, 22 Apr 1996 18:37:45 -0700 >From: Del Seay >Subject: Re: Elevated Guywire Anchor Posts >Rod Greene wrote: >> >> Maybe others can comment on this too, but I have heard of pouring concrete >> inside the pipe to make it much stronger. I have steel I beams for my >> elevated guy posts. Found them at the local electrical utility surplus yard >> (they were new galvanized beams from a project that never was completed). >> You might check your utility as a cheap source of heavy material. >> >> 73, Rod > >Rod & Stan, W7NI made some good points. Stan's comment to not use them >is important. However, if there is not sufficient real estate to get >proper angle on the guys, you can make it up with Sidewalk Guying, >such as you suggested. Several important do's. > Do use galvanized Steel I-Beams, rather than tubular, due to > breaking strength. > Do go as deep as possible. (100' tower, I'd go minimum of 10 feet!) > Do Not disturb the adjacent earth. Make the hole as square as > possible, and pour the entire hole. Disturbed earth will separate, > even if tamped. >And - if you're not comfortable with what you're doing, enlist the >help of a professional. -- de KL7HF While I agree I would have some reservations about using the pipe you have without being able to make a good guesstimate of it's physical properties, the use of elevated guy points is quite feasible and doesn't require the overkill that has been suggested. This is, after all, only 90 feet of Rohn 45. I have 110' of Rohn 45 with 3 sets of guys anchored approximately 85 feet from the base (80%) using 10 foot pieces of 1/2 " angle steel, with just over 4 feet in 2/3 yard of concrete each, i.e. almost 6' above ground. The long edge points toward the tower, with the corner cut off and a hold punched for the 3 point equalizer plate. In the ground, there are 2 holes punched near the bottom for 2 one foot pieces of 1/2 inch rebar which are tied together at their intersection. It is important to note that these were designed and stamped by a PE, which my county requires of all tower drawings. He specifically nixed using a plain 8" I beam. This is because the web in an I-beam is fairly thin, i.e.. you don't want to attach the guy plate to a hole in the web. If you need the strength of an I beam, you should have a tab welded onto the side of it instead. This is fine, but much more expensive than the 1/2" angle if you are paying someone else to do the welding, etc. N3RR went this route on his tower, but he's got 130 feet of heavy AB105 with TONS of antennas on it. He also spent about 3 times as much money on the "posts". It's important that whatever you use as a "post", should have some sort of plate or rods tied in at the bottom so that it has no chance of pulling out of the block of concrete. My tower has been up 1.5 years now, sees an inordinate amount of wind, rain, and ice, and is not lightly loaded with 3 stacked KT34XA's, a 402CD, several wire antennas with some sideload on the tower, and several runs of good-sized hardline, etc. Note that all designs of this sort can vary dramatically if you have loose soil, sand, etc. Mine is moderately hard clay, so it holds fairly well. -- Tyler kf3p@cais.com ===== I'm working with the Stanford Radio Club, W6YX, on the installation of some new towers. They are thinking of elevated guy posts, and will have them engineered if they go ahead. I'll pass along the result. I've seen several guy post installations, but the overturning moment on the post can rotate an unguyed post in the ground. Concrete should be poured against "undisturbed earth" in the tower base and guy anchor holes per the Rohn catalog drawings. Also, hollow tower and guy post legs must be able to drain, or the trapped water will freeze and split the tube. This is a potential problem in the rotating tower bearings that have a solid steel rod that goes into the tower legs, and it's not a good idea to drill holes in the legs at this high-stress point. More rebar rather than too little is always good insurance. The lightning ground rod goes outside the concrete in general practice. Lastly, it's customary to throw coin of the realm into the hole before pouring concrete; this is an ancient practice that deals with evil spirits and noxious rays, so don't cheap out here. 73 de Dave, W6QHS (now W6NL) ===== dave makes good points as always....i have used steel tubing for guy supports myself. the turning moment that dave mentions is an important consideration. i put a couple of pieces of re-bar in each tube and then filled them with concrete....i also tilted the tubes away from the tower 2-3 degrees. steel tubing can be very expensive if purchased new.....look for a scrap steel house and save a bundle! i also had a local welder weld guy wire ears on the free end and a cross bar on the buried portion. the installation never showed any signs of tipping or twisting in the ground although the installation was not up very long. -- AI7B ===== Charlie Ocker wrote: > > I'd like to bring guywires to elevated posts. Thinking 3 or 4 feet > above ground. It's a great way to terminate those pesky guywires. I use this method along with a great number of local Blackhole stations. My guy "posts" are made from 8" wide flange, 24-28 lb/foot class, I-beams. They started life holding up some building. I bought them locally as scrap and had them cut into 10' lengths. One flange was removed at the top and holes were bored through to accept the turnbuckles. The went down into 5' deep, 30" diameter bored holes, anchored with 1 yard of concrete. They work NICE and look pretty good too ! Just make sure you use WIDE FLANGE beams and get a heavy enough wall thickness. The beams are rated by weight, in lbs/foot. Don't settle for anything less then around 24 lbs/foot. This will give you satisfactory flange and web thickness to do the job. They are overkill for the vast majority of amateur installations. Since you're local, you're welcome to stop by and investigate for your self. Matter of fact, I have three more assemblies laying in the driveway for another tower. Enjoy ! ---------------------------###----------------------------- PROBE ELECTRONICS 100 Higgins Road, Park Ridge IL 60068 USA Keith J. Morehouse / WB9TIY / Society of Midwest Contesters 847-696-2828 FAX: 847-698-2045 e-mail: blckhole@ripco.com ---------------------------###----------------------------- ===== From: Chad Kurszewski WE9V To: towertalk@contesting.com, k5tr@contesting.com Date: Thu, 12 Mar 1998 13:51:31 -0600 Subject: [TowerTalk] Elevated Guy Anchors Summary Wow, what a response. There were about 30 responses in less than one day. To summarize, I made a table, sorted by tower height, as to the specifications that were used to construct the anchor. Note how few of the concrete pours are >2 Cu.Yd., which by the way, are the some of the ones designed by a PE. Also, there was an excellent message by Arliss, W7XU, which has some excellent data from Dick, K5IU, a ME who does the Rotating Tower Systems thing. I attached the message in it's entirety below. Conclusions? There's a wide variety of installs, here. Some of them I would probably bet money that they wouldn't survive 80MPH winds. What I forgot to mention is that some of the below examples have gotten pulled out of plumb. Using the same calculations as for an antenna mast, a 4" x 0.25" wall pipe would snap off (bend) at the concrete in my installation if it stuck out of the concrete more than 3'!! (90' tower, 80MPH) And some are using it 6' or even 10' out of the ground! What am I going to do? Dunno. 6" pipe minimum, or W8x15 I-beam, 3-5 feet out of ground, and because of the large overturning/lever action, probably a deep hole, 5-6' deep. Also, like the Rohn standard anchors (4b and larger), I will probably make the concrete wider being "broadside" to the tower and rebar the width of the concrete. Thanks for all the messages! Chad Twr Ant Elevated Guy Post Anchor Data Hght Load Type Size Len In GndOut GndCu.Yds. Size Deep ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- Pipe 6" 10 4 6 4 HDBX I-beam 4" 11 4 7 T/O Pipe 4"x0.25 12 6 6 bell 7 60 Pipe 8"x0.375 10 3 7 0.11 1x1' 3 73 L I-beam 8" 5.5 3 2.5 1 3 75 Pipe 4" Sc40 10.5 4.5 6 0.17 1x1' 4.5 80 M Pipe 4" 6 3 3 0.09 1'dia 3 80 S I-beam 6" web 7.5 4 3.5 1.3 90 S Pipe 6" 8 3 5 0.75 3 90 I-beam 8 4 4 0.11 1'dia 4 93 S I-beam 4W-15 8 4 4 0.16 14"dia 4 100 L Pipe 6"x0.25 9 3 6 1 3.5 100 L I-beam 10W-24 11 6 5 2 3x3' 6 100 Pipe 5"x0.25 10 4 6 1 4 105 M Pipe 6" 8 3 5 0.75 3 120 L Pipe 4" 7 4 3 120 L Pipe 6" 12 6 6 2 3x3' 6 120 L Pipe 4"x0.25 7 4 3 1+ 4.5x? 4 130 I-beam 4" std 10 5 5 0.33 18" dia 5 130 I-beam 6" wide 10 5 5 1.5 5 130 Pipe 3"x0.25 8 5 3 0.06 8"dia 5 130 Pipe 5"x0.25 10 4 6 1 4 140 L I-beam 12" 9 5 4 3 4x4' 5 150 Pipe 7"x0.5 9+ 4 5 4.5 3.5x7 6 160 Pipe 8"x0.375 10 5 5 1.3 3' dia 5 192 Pipe 4" 13 3 10 HDBX is Rohn HDBX self-supporting tower T/O is a Tilt over tower Ant Load: S=small, M=medium, L=large Most measurements in feet. ------------------------ From: W7XU Arliss Reply-To: w7xu@dtgnet.com To: Chad Kurszewski WE9V Subject: Re: [TowerTalk] Elevated Guy Anchors The following information was from a talk K5IU (a mechanical engineer and owner of Rotating Tower Systems) gave at (I believe) the New Orleans DX convention a few years back: For posts 7-8 ft above ground: Installation Width and Ht. Length Small 2 ft 5 ft Med 3 9 Big 4 10 The above dimensions are for the concrete bunker. The post sits in the middle of the bunker. The top of the bunker is 1 ft below ground level. (Yes, that's right, almost 6 yards of concrete per anchor for a large installation). Post size: Round post, with guys attaching at 7-8 ft above ground Installation Post diameter Wall thickness Small 5" or larger 0.25" or more Med 7" or larger 0.38" or more Big 9" or larger 0.50" or more Wide flange I-beams, with guys at 7-8 ft above ground Installation Wide flange I-beam size, A36 steel Small W 6x12 (6" X 4" - 12 lbs/ft) Med W 8x15 (8" X 4" - 15 lbs/ft) Big W 10x33 (10" X 8" - 33 lbs/ft) What is a medium or big installation? I have a rotating Rohn 25 tower approximately 135 ft high. It has eight 17-el 2 meter antennas on it, stacked one above the other from 30 to 135 ft. The windload of each antenna is 2.7 sq. ft., plus phasing lines, etc. That qualifies as a medium size installation (per K5IU). I have another rotating tower, 140 ft high. Rohn 55. It's designed to hold a 10 ft dia. dish, a 6 ft. dia. dish, a 4 ft dia. dish, 8 long boom (~22 ft) yagis on 432, 4 long boom (~28 ft) yagis on 222, and a couple of vetical beams for 2m FM and 440 FM. That is a big installation. I have elevated guy posts for both of the above towers, and followed K5IU's guidelines for the concrete bunkers. I also did some reading on my own and discussed it with a friend who is a civil engineer -- it takes a lot of concrete and steel to make proper elevated guys. A friend of mine skimped when he put up what is probably a small system (a tribander and 2m beam on 70 ft of Rohn 25) and now his posts are pulled out of plumb. Hope that gives you some ideas. -- Arliss W7XU --- Chad Kurszewski, WE9V e-mail: Chad_Kurszewski@csg.mot.com ============================================================= From: Gerald Smith To: DavidC , towertalk@contesting.com Date: Tue, 28 Sep 1999 08:54:36 -0400 Subject: Re: [TowerTalk] Calculating Raised Guy Height-Lengths? I just went through similar engineering with a PE. The PE specified square tubular construction steel (TS), 7" x 7" x 3/8". Further, of 8.5 feet, 5' above grade, 1' in grade, 2 1/2' in concrete. The concrete is 5' x 5' x 5', the top of which is 1' below grade. #4 rebar is used 12" on center, each way. As to connection to the TS, the PE specified a plate through the top of the TS, in a slit. The plate is 12" x 12" x 1/2". A 1" round bar is welded to the plate, at least 4". A guy equalizer plate is welded to the other end of the round bar. Remember, you must have something attached and protruding to the bottom of the TS for the concrete to adhere. In my case, 8 each 1/2" x 6" protrusions, welded to the TS. The are called "Nelsons" or "H.A.S." You might want to consult a local PE for more detail and to be safe. Remember, the type of earth in your area may vary thereby altering the requirements. Gerry, W6TER DavidC wrote: > > Progress at last! The trees have come down, the area is > being cleared, tower-time approaches! > > One of the three guy anchor points encroaches upon the yard. > I want to use a raised guy anchor at that point. > > My tower is a 60 foot Rohn 45 and if I have understood the > Rohn manual the guy points are 48 feet out from the base > and 85 feet apart around the perimeter. > > Higher-math is one of my many weaknesses. If I raise a guy > point to 7 feet how much less than 48 feet is that guy point > from the tower base, please? > > I haven't yet found a local construction-site-surplus-source for > I-beams but when I do how much longer than the 7 feet above > ground does the beam need to be? I was guessing that I need > a 10 foot piece so that I may put 3 feet in concrete. Any > additional advice as to setting the beam properly is appreciated. > > Also, for cosmetic reasons I am thinking of sliding a piece of > PVC over the I-beam and filling it with concrete. Is this an OK > idea or do folks have better suggestions? Here in central > Florida the wood options are limited due to termites and a > hollow PVC tube makes too friendly of a home for beasties. > > Finally, does the I-beam come with attachment holes or > will I need to find someone who can drill one? Or is there > another way to attach the guy to it? (I am using Phillystran > and the yard will be well fenced. Vandalism is unlikely and > the grass is very short so fire isn't an issue either.) > > Thanks! & 73, DavidC K1YP >>